Line data Source code
1 : //! This module acts as a switchboard to access different repositories managed by this
2 : //! page server.
3 :
4 : use std::borrow::Cow;
5 : use std::cmp::Ordering;
6 : use std::collections::{BTreeMap, HashMap, HashSet};
7 : use std::ops::Deref;
8 : use std::sync::Arc;
9 : use std::time::Duration;
10 :
11 : use anyhow::Context;
12 : use camino::{Utf8DirEntry, Utf8Path, Utf8PathBuf};
13 : use futures::StreamExt;
14 : use itertools::Itertools;
15 : use pageserver_api::key::Key;
16 : use pageserver_api::models::{DetachBehavior, LocationConfigMode};
17 : use pageserver_api::shard::{
18 : ShardCount, ShardIdentity, ShardIndex, ShardNumber, ShardStripeSize, TenantShardId,
19 : };
20 : use pageserver_api::upcall_api::ReAttachResponseTenant;
21 : use rand::Rng;
22 : use rand::distr::Alphanumeric;
23 : use remote_storage::TimeoutOrCancel;
24 : use sysinfo::SystemExt;
25 : use tokio::fs;
26 : use tokio::task::JoinSet;
27 : use tokio_util::sync::CancellationToken;
28 : use tracing::*;
29 : use utils::crashsafe::path_with_suffix_extension;
30 : use utils::fs_ext::PathExt;
31 : use utils::generation::Generation;
32 : use utils::id::{TenantId, TimelineId};
33 : use utils::{backoff, completion, crashsafe};
34 :
35 : use super::remote_timeline_client::remote_tenant_path;
36 : use super::secondary::SecondaryTenant;
37 : use super::timeline::detach_ancestor::{self, PreparedTimelineDetach};
38 : use super::{GlobalShutDown, TenantSharedResources};
39 : use crate::config::PageServerConf;
40 : use crate::context::{DownloadBehavior, RequestContext};
41 : use crate::controller_upcall_client::{
42 : RetryForeverError, StorageControllerUpcallApi, StorageControllerUpcallClient,
43 : };
44 : use crate::deletion_queue::DeletionQueueClient;
45 : use crate::http::routes::ACTIVE_TENANT_TIMEOUT;
46 : use crate::metrics::{LOCAL_DATA_LOSS_SUSPECTED, TENANT, TENANT_MANAGER as METRICS};
47 : use crate::task_mgr::{BACKGROUND_RUNTIME, TaskKind};
48 : use crate::tenant::config::{
49 : AttachedLocationConfig, AttachmentMode, LocationConf, LocationMode, SecondaryLocationConfig,
50 : };
51 : use crate::tenant::span::debug_assert_current_span_has_tenant_id;
52 : use crate::tenant::storage_layer::inmemory_layer;
53 : use crate::tenant::timeline::ShutdownMode;
54 : use crate::tenant::timeline::layer_manager::LayerManagerLockHolder;
55 : use crate::tenant::{
56 : AttachedTenantConf, GcError, LoadConfigError, SpawnMode, TenantShard, TenantState,
57 : };
58 : use crate::virtual_file::MaybeFatalIo;
59 : use crate::{InitializationOrder, TEMP_FILE_SUFFIX};
60 :
61 : /// For a tenant that appears in TenantsMap, it may either be
62 : /// - `Attached`: has a full Tenant object, is elegible to service
63 : /// reads and ingest WAL.
64 : /// - `Secondary`: is only keeping a local cache warm.
65 : ///
66 : /// Secondary is a totally distinct state rather than being a mode of a `Tenant`, because
67 : /// that way we avoid having to carefully switch a tenant's ingestion etc on and off during
68 : /// its lifetime, and we can preserve some important safety invariants like `Tenant` always
69 : /// having a properly acquired generation (Secondary doesn't need a generation)
70 : #[derive(Clone)]
71 : pub(crate) enum TenantSlot {
72 : Attached(Arc<TenantShard>),
73 : Secondary(Arc<SecondaryTenant>),
74 : /// In this state, other administrative operations acting on the TenantId should
75 : /// block, or return a retry indicator equivalent to HTTP 503.
76 : InProgress(utils::completion::Barrier),
77 : }
78 :
79 : impl std::fmt::Debug for TenantSlot {
80 0 : fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
81 0 : match self {
82 0 : Self::Attached(tenant) => write!(f, "Attached({})", tenant.current_state()),
83 0 : Self::Secondary(_) => write!(f, "Secondary"),
84 0 : Self::InProgress(_) => write!(f, "InProgress"),
85 : }
86 0 : }
87 : }
88 :
89 : impl TenantSlot {
90 : /// Return the `Tenant` in this slot if attached, else None
91 0 : fn get_attached(&self) -> Option<&Arc<TenantShard>> {
92 0 : match self {
93 0 : Self::Attached(t) => Some(t),
94 0 : Self::Secondary(_) => None,
95 0 : Self::InProgress(_) => None,
96 : }
97 0 : }
98 : }
99 :
100 : /// The tenants known to the pageserver.
101 : /// The enum variants are used to distinguish the different states that the pageserver can be in.
102 : pub(crate) enum TenantsMap {
103 : /// [`init_tenant_mgr`] is not done yet.
104 : Initializing,
105 : /// [`init_tenant_mgr`] is done, all on-disk tenants have been loaded.
106 : /// New tenants can be added using [`TenantManager::tenant_map_acquire_slot`].
107 : Open(BTreeMap<TenantShardId, TenantSlot>),
108 : /// The pageserver has entered shutdown mode via [`TenantManager::shutdown`].
109 : /// Existing tenants are still accessible, but no new tenants can be created.
110 : ShuttingDown(BTreeMap<TenantShardId, TenantSlot>),
111 : }
112 :
113 : /// When resolving a TenantId to a shard, we may be looking for the 0th
114 : /// shard, or we might be looking for whichever shard holds a particular page.
115 : #[derive(Copy, Clone)]
116 : pub(crate) enum ShardSelector {
117 : /// Only return the 0th shard, if it is present. If a non-0th shard is present,
118 : /// ignore it.
119 : Zero,
120 : /// Pick the shard that holds this key
121 : Page(Key),
122 : /// The shard ID is known: pick the given shard
123 : Known(ShardIndex),
124 : }
125 :
126 : /// A convenience for use with the re_attach ControllerUpcallClient function: rather
127 : /// than the serializable struct, we build this enum that encapsulates
128 : /// the invariant that attached tenants always have generations.
129 : ///
130 : /// This represents the subset of a LocationConfig that we receive during re-attach.
131 : pub(crate) enum TenantStartupMode {
132 : Attached((AttachmentMode, Generation, ShardStripeSize)),
133 : Secondary,
134 : }
135 :
136 : impl TenantStartupMode {
137 : /// Return the generation & mode that should be used when starting
138 : /// this tenant.
139 : ///
140 : /// If this returns None, the re-attach struct is in an invalid state and
141 : /// should be ignored in the response.
142 0 : fn from_reattach_tenant(rart: ReAttachResponseTenant) -> Option<Self> {
143 0 : match (rart.mode, rart.r#gen) {
144 0 : (LocationConfigMode::Detached, _) => None,
145 0 : (LocationConfigMode::Secondary, _) => Some(Self::Secondary),
146 0 : (LocationConfigMode::AttachedMulti, Some(g)) => Some(Self::Attached((
147 0 : AttachmentMode::Multi,
148 0 : Generation::new(g),
149 0 : rart.stripe_size,
150 0 : ))),
151 0 : (LocationConfigMode::AttachedSingle, Some(g)) => Some(Self::Attached((
152 0 : AttachmentMode::Single,
153 0 : Generation::new(g),
154 0 : rart.stripe_size,
155 0 : ))),
156 0 : (LocationConfigMode::AttachedStale, Some(g)) => Some(Self::Attached((
157 0 : AttachmentMode::Stale,
158 0 : Generation::new(g),
159 0 : rart.stripe_size,
160 0 : ))),
161 : _ => {
162 0 : tracing::warn!(
163 0 : "Received invalid re-attach state for tenant {}: {rart:?}",
164 : rart.id
165 : );
166 0 : None
167 : }
168 : }
169 0 : }
170 : }
171 :
172 : /// Result type for looking up a TenantId to a specific shard
173 : pub(crate) enum ShardResolveResult {
174 : NotFound,
175 : Found(Arc<TenantShard>),
176 : // Wait for this barrrier, then query again
177 : InProgress(utils::completion::Barrier),
178 : }
179 :
180 : impl TenantsMap {
181 : /// Convenience function for typical usage, where we want to get a `Tenant` object, for
182 : /// working with attached tenants. If the TenantId is in the map but in Secondary state,
183 : /// None is returned.
184 0 : pub(crate) fn get(&self, tenant_shard_id: &TenantShardId) -> Option<&Arc<TenantShard>> {
185 0 : match self {
186 0 : TenantsMap::Initializing => None,
187 0 : TenantsMap::Open(m) | TenantsMap::ShuttingDown(m) => {
188 0 : m.get(tenant_shard_id).and_then(|slot| slot.get_attached())
189 : }
190 : }
191 0 : }
192 :
193 : #[cfg(all(debug_assertions, not(test)))]
194 0 : pub(crate) fn len(&self) -> usize {
195 0 : match self {
196 0 : TenantsMap::Initializing => 0,
197 0 : TenantsMap::Open(m) | TenantsMap::ShuttingDown(m) => m.len(),
198 : }
199 0 : }
200 : }
201 :
202 : /// Precursor to deletion of a tenant dir: we do a fast rename to a tmp path, and then
203 : /// the slower actual deletion in the background.
204 : ///
205 : /// This is "safe" in that that it won't leave behind a partially deleted directory
206 : /// at the original path, because we rename with TEMP_FILE_SUFFIX before starting deleting
207 : /// the contents.
208 : ///
209 : /// This is pageserver-specific, as it relies on future processes after a crash to check
210 : /// for TEMP_FILE_SUFFIX when loading things.
211 0 : async fn safe_rename_tenant_dir(path: impl AsRef<Utf8Path>) -> std::io::Result<Utf8PathBuf> {
212 0 : let parent = path
213 0 : .as_ref()
214 0 : .parent()
215 : // It is invalid to call this function with a relative path. Tenant directories
216 : // should always have a parent.
217 0 : .ok_or(std::io::Error::new(
218 0 : std::io::ErrorKind::InvalidInput,
219 : "Path must be absolute",
220 0 : ))?;
221 0 : let rand_suffix = rand::rng()
222 0 : .sample_iter(&Alphanumeric)
223 0 : .take(8)
224 0 : .map(char::from)
225 0 : .collect::<String>()
226 0 : + TEMP_FILE_SUFFIX;
227 0 : let tmp_path = path_with_suffix_extension(&path, &rand_suffix);
228 0 : fs::rename(path.as_ref(), &tmp_path).await?;
229 0 : fs::File::open(parent)
230 0 : .await?
231 0 : .sync_all()
232 0 : .await
233 0 : .maybe_fatal_err("safe_rename_tenant_dir")?;
234 0 : Ok(tmp_path)
235 0 : }
236 :
237 : /// See [`Self::spawn`].
238 : #[derive(Clone, Default)]
239 : pub struct BackgroundPurges(tokio_util::task::TaskTracker);
240 :
241 : impl BackgroundPurges {
242 : /// When we have moved a tenant's content to a temporary directory, we may delete it lazily in
243 : /// the background, and thereby avoid blocking any API requests on this deletion completing.
244 : ///
245 : /// Although we are cleaning up the tenant, this task is not meant to be bound by the lifetime of the tenant in memory.
246 : /// Thus the [`BackgroundPurges`] type to keep track of these tasks.
247 0 : pub fn spawn(&self, tmp_path: Utf8PathBuf) {
248 : // because on shutdown we close and wait, we are misusing TaskTracker a bit.
249 : //
250 : // so first acquire a token, then check if the tracker has been closed. the tracker might get closed
251 : // right after, but at least the shutdown will wait for what we are spawning next.
252 0 : let token = self.0.token();
253 :
254 0 : if self.0.is_closed() {
255 0 : warn!(
256 : %tmp_path,
257 0 : "trying to spawn background purge during shutdown, ignoring"
258 : );
259 0 : return;
260 0 : }
261 :
262 0 : let span = info_span!(parent: None, "background_purge", %tmp_path);
263 :
264 0 : let task = move || {
265 0 : let _token = token;
266 0 : let _entered = span.entered();
267 0 : if let Err(error) = std::fs::remove_dir_all(tmp_path.as_path()) {
268 : // should we fatal_io_error here?
269 0 : warn!(%error, "failed to purge tenant directory");
270 0 : }
271 0 : };
272 :
273 0 : BACKGROUND_RUNTIME.spawn_blocking(task);
274 0 : }
275 :
276 : /// When this future completes, all background purges have completed.
277 : /// The first poll of the future will already lock out new background purges spawned via [`Self::spawn`].
278 : ///
279 : /// Concurrent calls will coalesce.
280 : ///
281 : /// # Cancellation-Safety
282 : ///
283 : /// If this future is dropped before polled to completion, concurrent and subsequent
284 : /// instances of this future will continue to be correct.
285 : #[instrument(skip_all)]
286 : pub async fn shutdown(&self) {
287 : // forbid new tasks (can be called many times)
288 : self.0.close();
289 : self.0.wait().await;
290 : }
291 : }
292 :
293 : /// Responsible for storing and mutating the collection of all tenants
294 : /// that this pageserver has state for.
295 : ///
296 : /// Every Tenant and SecondaryTenant instance lives inside the TenantManager.
297 : ///
298 : /// The most important role of the TenantManager is to prevent conflicts: e.g. trying to attach
299 : /// the same tenant twice concurrently, or trying to configure the same tenant into secondary
300 : /// and attached modes concurrently.
301 : pub struct TenantManager {
302 : conf: &'static PageServerConf,
303 : tenants: std::sync::RwLock<TenantsMap>,
304 : resources: TenantSharedResources,
305 :
306 : // Long-running operations that happen outside of a [`Tenant`] lifetime should respect this token.
307 : // This is for edge cases like tenant deletion. In normal cases (within a Tenant lifetime),
308 : // tenants have their own cancellation tokens, which we fire individually in [`Self::shutdown`], or
309 : // when the tenant detaches.
310 : cancel: CancellationToken,
311 :
312 : background_purges: BackgroundPurges,
313 : }
314 :
315 0 : fn emergency_generations(
316 0 : tenant_confs: &HashMap<TenantShardId, Result<LocationConf, LoadConfigError>>,
317 0 : ) -> HashMap<TenantShardId, TenantStartupMode> {
318 0 : tenant_confs
319 0 : .iter()
320 0 : .filter_map(|(tid, lc)| {
321 0 : let lc = match lc {
322 0 : Ok(lc) => lc,
323 0 : Err(_) => return None,
324 : };
325 : Some((
326 0 : *tid,
327 0 : match &lc.mode {
328 0 : LocationMode::Attached(alc) => TenantStartupMode::Attached((
329 0 : alc.attach_mode,
330 0 : alc.generation,
331 0 : lc.shard.stripe_size,
332 0 : )),
333 0 : LocationMode::Secondary(_) => TenantStartupMode::Secondary,
334 : },
335 : ))
336 0 : })
337 0 : .collect()
338 0 : }
339 :
340 0 : async fn init_load_generations(
341 0 : conf: &'static PageServerConf,
342 0 : tenant_confs: &HashMap<TenantShardId, Result<LocationConf, LoadConfigError>>,
343 0 : resources: &TenantSharedResources,
344 0 : cancel: &CancellationToken,
345 0 : ) -> anyhow::Result<Option<HashMap<TenantShardId, TenantStartupMode>>> {
346 0 : let generations = if conf.control_plane_emergency_mode {
347 0 : error!(
348 0 : "Emergency mode! Tenants will be attached unsafely using their last known generation"
349 : );
350 0 : emergency_generations(tenant_confs)
351 : } else {
352 0 : let client = StorageControllerUpcallClient::new(conf, cancel);
353 0 : info!("Calling {} API to re-attach tenants", client.base_url());
354 : // If we are configured to use the control plane API, then it is the source of truth for what tenants to load.
355 0 : let empty_local_disk = tenant_confs.is_empty();
356 0 : match client.re_attach(conf, empty_local_disk).await {
357 0 : Ok(tenants) => tenants
358 0 : .into_iter()
359 0 : .flat_map(|(id, rart)| {
360 0 : TenantStartupMode::from_reattach_tenant(rart).map(|tsm| (id, tsm))
361 0 : })
362 0 : .collect(),
363 : Err(RetryForeverError::ShuttingDown) => {
364 0 : anyhow::bail!("Shut down while waiting for control plane re-attach response")
365 : }
366 : }
367 : };
368 :
369 : // The deletion queue needs to know about the startup attachment state to decide which (if any) stored
370 : // deletion list entries may still be valid. We provide that by pushing a recovery operation into
371 : // the queue. Sequential processing of te queue ensures that recovery is done before any new tenant deletions
372 : // are processed, even though we don't block on recovery completing here.
373 0 : let attached_tenants = generations
374 0 : .iter()
375 0 : .flat_map(|(id, start_mode)| {
376 0 : match start_mode {
377 0 : TenantStartupMode::Attached((_mode, generation, _stripe_size)) => Some(generation),
378 0 : TenantStartupMode::Secondary => None,
379 : }
380 0 : .map(|gen_| (*id, *gen_))
381 0 : })
382 0 : .collect();
383 0 : resources.deletion_queue_client.recover(attached_tenants)?;
384 :
385 0 : Ok(Some(generations))
386 0 : }
387 :
388 : /// Given a directory discovered in the pageserver's tenants/ directory, attempt
389 : /// to load a tenant config from it.
390 : ///
391 : /// If we cleaned up something expected (like an empty dir or a temp dir), return None.
392 0 : fn load_tenant_config(
393 0 : conf: &'static PageServerConf,
394 0 : tenant_shard_id: TenantShardId,
395 0 : dentry: Utf8DirEntry,
396 0 : ) -> Option<Result<LocationConf, LoadConfigError>> {
397 0 : let tenant_dir_path = dentry.path().to_path_buf();
398 0 : if crate::is_temporary(&tenant_dir_path) {
399 0 : info!("Found temporary tenant directory, removing: {tenant_dir_path}");
400 : // No need to use safe_remove_tenant_dir_all because this is already
401 : // a temporary path
402 0 : std::fs::remove_dir_all(&tenant_dir_path).fatal_err("delete temporary tenant dir");
403 0 : return None;
404 0 : }
405 :
406 : // This case happens if we crash during attachment before writing a config into the dir
407 0 : let is_empty = tenant_dir_path
408 0 : .is_empty_dir()
409 0 : .fatal_err("Checking for empty tenant dir");
410 0 : if is_empty {
411 0 : info!("removing empty tenant directory {tenant_dir_path:?}");
412 0 : std::fs::remove_dir(&tenant_dir_path).fatal_err("delete empty tenant dir");
413 0 : return None;
414 0 : }
415 :
416 0 : Some(TenantShard::load_tenant_config(conf, &tenant_shard_id))
417 0 : }
418 :
419 : /// Initial stage of load: walk the local tenants directory, clean up any temp files,
420 : /// and load configurations for the tenants we found.
421 : ///
422 : /// Do this in parallel, because we expect 10k+ tenants, so serial execution can take
423 : /// seconds even on reasonably fast drives.
424 0 : async fn init_load_tenant_configs(
425 0 : conf: &'static PageServerConf,
426 0 : ) -> HashMap<TenantShardId, Result<LocationConf, LoadConfigError>> {
427 0 : let tenants_dir = conf.tenants_path();
428 :
429 0 : let dentries = tokio::task::spawn_blocking(move || -> Vec<Utf8DirEntry> {
430 0 : let context = format!("read tenants dir {tenants_dir}");
431 0 : let dir_entries = tenants_dir.read_dir_utf8().fatal_err(&context);
432 :
433 0 : dir_entries
434 0 : .collect::<Result<Vec<_>, std::io::Error>>()
435 0 : .fatal_err(&context)
436 0 : })
437 0 : .await
438 0 : .expect("Config load task panicked");
439 :
440 0 : let mut configs = HashMap::new();
441 :
442 0 : let mut join_set = JoinSet::new();
443 0 : for dentry in dentries {
444 0 : let tenant_shard_id = match dentry.file_name().parse::<TenantShardId>() {
445 0 : Ok(id) => id,
446 : Err(_) => {
447 0 : warn!(
448 0 : "Invalid tenant path (garbage in our repo directory?): '{}'",
449 0 : dentry.file_name()
450 : );
451 0 : continue;
452 : }
453 : };
454 :
455 0 : join_set.spawn_blocking(move || {
456 0 : (
457 0 : tenant_shard_id,
458 0 : load_tenant_config(conf, tenant_shard_id, dentry),
459 0 : )
460 0 : });
461 : }
462 :
463 0 : while let Some(r) = join_set.join_next().await {
464 0 : let (tenant_shard_id, tenant_config) = r.expect("Panic in config load task");
465 0 : if let Some(tenant_config) = tenant_config {
466 0 : configs.insert(tenant_shard_id, tenant_config);
467 0 : }
468 : }
469 :
470 0 : configs
471 0 : }
472 :
473 : #[derive(Debug, thiserror::Error)]
474 : pub(crate) enum DeleteTenantError {
475 : #[error("Tenant map slot error {0}")]
476 : SlotError(#[from] TenantSlotError),
477 :
478 : #[error("Cancelled")]
479 : Cancelled,
480 :
481 : #[error(transparent)]
482 : Other(#[from] anyhow::Error),
483 : }
484 :
485 : /// Initialize repositories at `Initializing` state.
486 0 : pub fn init(
487 0 : conf: &'static PageServerConf,
488 0 : background_purges: BackgroundPurges,
489 0 : resources: TenantSharedResources,
490 0 : cancel: CancellationToken,
491 0 : ) -> TenantManager {
492 0 : TenantManager {
493 0 : conf,
494 0 : tenants: std::sync::RwLock::new(TenantsMap::Initializing),
495 0 : resources,
496 0 : cancel,
497 0 : background_purges,
498 0 : }
499 0 : }
500 :
501 : /// Transition repositories from `Initializing` state to `Open` state with locally available timelines.
502 : /// Timelines that are only partially available locally (remote storage has more data than this pageserver)
503 : /// are scheduled for download and added to the tenant once download is completed.
504 : #[instrument(skip_all)]
505 : pub async fn init_tenant_mgr(
506 : tenant_manager: Arc<TenantManager>,
507 : init_order: InitializationOrder,
508 : ) -> anyhow::Result<()> {
509 : debug_assert!(matches!(
510 : *tenant_manager.tenants.read().unwrap(),
511 : TenantsMap::Initializing
512 : ));
513 : let mut tenants = BTreeMap::new();
514 :
515 : let ctx = RequestContext::todo_child(TaskKind::Startup, DownloadBehavior::Warn);
516 :
517 : let conf = tenant_manager.conf;
518 : let resources = &tenant_manager.resources;
519 : let cancel = &tenant_manager.cancel;
520 : let background_purges = &tenant_manager.background_purges;
521 :
522 : // Initialize dynamic limits that depend on system resources
523 : let system_memory =
524 : sysinfo::System::new_with_specifics(sysinfo::RefreshKind::new().with_memory())
525 : .total_memory();
526 : let max_ephemeral_layer_bytes =
527 : conf.ephemeral_bytes_per_memory_kb as u64 * (system_memory / 1024);
528 : tracing::info!(
529 : "Initialized ephemeral layer size limit to {max_ephemeral_layer_bytes}, for {system_memory} bytes of memory"
530 : );
531 : inmemory_layer::GLOBAL_RESOURCES.max_dirty_bytes.store(
532 : max_ephemeral_layer_bytes,
533 : std::sync::atomic::Ordering::Relaxed,
534 : );
535 :
536 : // Scan local filesystem for attached tenants
537 : let tenant_configs = init_load_tenant_configs(conf).await;
538 :
539 : // Determine which tenants are to be secondary or attached, and in which generation
540 : let tenant_modes = init_load_generations(conf, &tenant_configs, resources, cancel).await?;
541 :
542 : // Hadron local SSD check: Raise an alert if our local filesystem does not contain any tenants but the re-attach request returned tenants.
543 : // This can happen if the PS suffered a Kubernetes node failure resulting in loss of all local data, but recovered quickly on another node
544 : // so the Storage Controller has not had the time to move tenants out.
545 : let data_loss_suspected = if let Some(tenant_modes) = &tenant_modes {
546 : tenant_configs.is_empty() && !tenant_modes.is_empty()
547 : } else {
548 : false
549 : };
550 : if data_loss_suspected {
551 : tracing::error!(
552 : "Local data loss suspected: no tenants found on local filesystem, but re-attach request returned tenants"
553 : );
554 : }
555 : LOCAL_DATA_LOSS_SUSPECTED.set(if data_loss_suspected { 1 } else { 0 });
556 :
557 : tracing::info!(
558 : "Attaching {} tenants at startup, warming up {} at a time",
559 : tenant_configs.len(),
560 : conf.concurrent_tenant_warmup.initial_permits()
561 : );
562 : TENANT.startup_scheduled.inc_by(tenant_configs.len() as u64);
563 :
564 : // Accumulate futures for writing tenant configs, so that we can execute in parallel
565 : let mut config_write_futs = Vec::new();
566 :
567 : // Update the location configs according to the re-attach response and persist them to disk
568 : tracing::info!("Updating {} location configs", tenant_configs.len());
569 : for (tenant_shard_id, location_conf) in tenant_configs {
570 : let tenant_dir_path = conf.tenant_path(&tenant_shard_id);
571 :
572 : let mut location_conf = match location_conf {
573 : Ok(l) => l,
574 : Err(e) => {
575 : // This should only happen in the case of a serialization bug or critical local I/O error: we cannot load this tenant
576 : error!(tenant_id=%tenant_shard_id.tenant_id, shard_id=%tenant_shard_id.shard_slug(), "Failed to load tenant config, failed to {e:#}");
577 : continue;
578 : }
579 : };
580 :
581 : // FIXME: if we were attached, and get demoted to secondary on re-attach, we
582 : // don't have a place to get a config.
583 : // (https://github.com/neondatabase/neon/issues/5377)
584 : const DEFAULT_SECONDARY_CONF: SecondaryLocationConfig =
585 : SecondaryLocationConfig { warm: true };
586 :
587 : if let Some(tenant_modes) = &tenant_modes {
588 : // We have a generation map: treat it as the authority for whether
589 : // this tenant is really attached.
590 : match tenant_modes.get(&tenant_shard_id) {
591 : None => {
592 : info!(tenant_id=%tenant_shard_id.tenant_id, shard_id=%tenant_shard_id.shard_slug(), "Detaching tenant, control plane omitted it in re-attach response");
593 :
594 : match safe_rename_tenant_dir(&tenant_dir_path).await {
595 : Ok(tmp_path) => {
596 : background_purges.spawn(tmp_path);
597 : }
598 : Err(e) => {
599 : error!(tenant_id=%tenant_shard_id.tenant_id, shard_id=%tenant_shard_id.shard_slug(),
600 : "Failed to move detached tenant directory '{tenant_dir_path}': {e:?}");
601 : }
602 : };
603 :
604 : // We deleted local content: move on to next tenant, don't try and spawn this one.
605 : continue;
606 : }
607 : Some(TenantStartupMode::Secondary) => {
608 : if !matches!(location_conf.mode, LocationMode::Secondary(_)) {
609 : location_conf.mode = LocationMode::Secondary(DEFAULT_SECONDARY_CONF);
610 : }
611 : }
612 : Some(TenantStartupMode::Attached((attach_mode, generation, stripe_size))) => {
613 : let old_gen_higher = match &location_conf.mode {
614 : LocationMode::Attached(AttachedLocationConfig {
615 : generation: old_generation,
616 : attach_mode: _attach_mode,
617 : }) => {
618 : if old_generation > generation {
619 : Some(old_generation)
620 : } else {
621 : None
622 : }
623 : }
624 : _ => None,
625 : };
626 : if let Some(old_generation) = old_gen_higher {
627 : tracing::error!(tenant_id=%tenant_shard_id.tenant_id, shard_id=%tenant_shard_id.shard_slug(),
628 : "Control plane gave decreasing generation ({generation:?}) in re-attach response for tenant that was attached in generation {:?}, demoting to secondary",
629 : old_generation
630 : );
631 :
632 : // We cannot safely attach this tenant given a bogus generation number, but let's avoid throwing away
633 : // local disk content: demote to secondary rather than detaching.
634 : location_conf.mode = LocationMode::Secondary(DEFAULT_SECONDARY_CONF);
635 : } else {
636 : location_conf.attach_in_generation(*attach_mode, *generation, *stripe_size);
637 : }
638 : }
639 : }
640 : } else {
641 : // Legacy mode: no generation information, any tenant present
642 : // on local disk may activate
643 : info!(tenant_id=%tenant_shard_id.tenant_id, shard_id=%tenant_shard_id.shard_slug(), "Starting tenant in legacy mode, no generation",);
644 : };
645 :
646 : // Presence of a generation number implies attachment: attach the tenant
647 : // if it wasn't already, and apply the generation number.
648 0 : config_write_futs.push(async move {
649 0 : let r =
650 0 : TenantShard::persist_tenant_config(conf, &tenant_shard_id, &location_conf).await;
651 0 : (tenant_shard_id, location_conf, r)
652 0 : });
653 : }
654 :
655 : // Execute config writes with concurrency, to avoid bottlenecking on local FS write latency
656 : tracing::info!(
657 : "Writing {} location config files...",
658 : config_write_futs.len()
659 : );
660 : let config_write_results = futures::stream::iter(config_write_futs)
661 : .buffer_unordered(16)
662 : .collect::<Vec<_>>()
663 : .await;
664 :
665 : tracing::info!(
666 : "Spawning {} tenant shard locations...",
667 : config_write_results.len()
668 : );
669 : // For those shards that have live configurations, construct `Tenant` or `SecondaryTenant` objects and start them running
670 : for (tenant_shard_id, location_conf, config_write_result) in config_write_results {
671 : // Writing a config to local disk is foundational to startup up tenants: panic if we can't.
672 : config_write_result.fatal_err("write tenant shard config file");
673 :
674 : let tenant_dir_path = conf.tenant_path(&tenant_shard_id);
675 : let shard_identity = location_conf.shard;
676 : let slot = match location_conf.mode {
677 : LocationMode::Attached(attached_conf) => TenantSlot::Attached(
678 : tenant_spawn(
679 : conf,
680 : tenant_shard_id,
681 : &tenant_dir_path,
682 : resources.clone(),
683 : AttachedTenantConf::new(conf, location_conf.tenant_conf, attached_conf),
684 : shard_identity,
685 : Some(init_order.clone()),
686 : SpawnMode::Lazy,
687 : &ctx,
688 : )
689 : .expect("global shutdown during init_tenant_mgr cannot happen"),
690 : ),
691 : LocationMode::Secondary(secondary_conf) => {
692 : info!(
693 : tenant_id = %tenant_shard_id.tenant_id,
694 : shard_id = %tenant_shard_id.shard_slug(),
695 : "Starting secondary tenant"
696 : );
697 : TenantSlot::Secondary(SecondaryTenant::new(
698 : tenant_shard_id,
699 : shard_identity,
700 : location_conf.tenant_conf,
701 : &secondary_conf,
702 : ))
703 : }
704 : };
705 :
706 : METRICS.slot_inserted(&slot);
707 : tenants.insert(tenant_shard_id, slot);
708 : }
709 :
710 : info!("Processed {} local tenants at startup", tenants.len());
711 :
712 : let mut tenant_map = tenant_manager.tenants.write().unwrap();
713 : *tenant_map = TenantsMap::Open(tenants);
714 :
715 : Ok(())
716 : }
717 :
718 : /// Wrapper for Tenant::spawn that checks invariants before running
719 : #[allow(clippy::too_many_arguments)]
720 0 : fn tenant_spawn(
721 0 : conf: &'static PageServerConf,
722 0 : tenant_shard_id: TenantShardId,
723 0 : tenant_path: &Utf8Path,
724 0 : resources: TenantSharedResources,
725 0 : location_conf: AttachedTenantConf,
726 0 : shard_identity: ShardIdentity,
727 0 : init_order: Option<InitializationOrder>,
728 0 : mode: SpawnMode,
729 0 : ctx: &RequestContext,
730 0 : ) -> Result<Arc<TenantShard>, GlobalShutDown> {
731 : // All these conditions should have been satisfied by our caller: the tenant dir exists, is a well formed
732 : // path, and contains a configuration file. Assertions that do synchronous I/O are limited to debug mode
733 : // to avoid impacting prod runtime performance.
734 0 : assert!(!crate::is_temporary(tenant_path));
735 0 : debug_assert!(tenant_path.is_dir());
736 0 : debug_assert!(
737 0 : conf.tenant_location_config_path(&tenant_shard_id)
738 0 : .try_exists()
739 0 : .unwrap()
740 : );
741 :
742 0 : TenantShard::spawn(
743 0 : conf,
744 0 : tenant_shard_id,
745 0 : resources,
746 0 : location_conf,
747 0 : shard_identity,
748 0 : init_order,
749 0 : mode,
750 0 : ctx,
751 : )
752 0 : }
753 :
754 : #[derive(thiserror::Error, Debug)]
755 : pub(crate) enum UpsertLocationError {
756 : #[error("Bad config request: {0}")]
757 : BadRequest(anyhow::Error),
758 :
759 : #[error("Cannot change config in this state: {0}")]
760 : Unavailable(#[from] TenantMapError),
761 :
762 : #[error("Tenant is already being modified")]
763 : InProgress,
764 :
765 : #[error("Failed to flush: {0}")]
766 : Flush(anyhow::Error),
767 :
768 : /// This error variant is for unexpected situations (soft assertions) where the system is in an unexpected state.
769 : #[error("Internal error: {0}")]
770 : InternalError(anyhow::Error),
771 : }
772 :
773 : impl TenantManager {
774 : /// Convenience function so that anyone with a TenantManager can get at the global configuration, without
775 : /// having to pass it around everywhere as a separate object.
776 0 : pub(crate) fn get_conf(&self) -> &'static PageServerConf {
777 0 : self.conf
778 0 : }
779 :
780 : /// Gets the attached tenant from the in-memory data, erroring if it's absent, in secondary mode, or currently
781 : /// undergoing a state change (i.e. slot is InProgress).
782 : ///
783 : /// The return TenantShard is not guaranteed to be active: check its status after obtaing it, or
784 : /// use [`TenantShard::wait_to_become_active`] before using it if you will do I/O on it.
785 0 : pub(crate) fn get_attached_tenant_shard(
786 0 : &self,
787 0 : tenant_shard_id: TenantShardId,
788 0 : ) -> Result<Arc<TenantShard>, GetTenantError> {
789 0 : let locked = self.tenants.read().unwrap();
790 :
791 0 : let peek_slot = tenant_map_peek_slot(&locked, &tenant_shard_id, TenantSlotPeekMode::Read)?;
792 :
793 0 : match peek_slot {
794 0 : Some(TenantSlot::Attached(tenant)) => Ok(Arc::clone(tenant)),
795 0 : Some(TenantSlot::InProgress(_)) => Err(GetTenantError::NotActive(tenant_shard_id)),
796 : None | Some(TenantSlot::Secondary(_)) => {
797 0 : Err(GetTenantError::ShardNotFound(tenant_shard_id))
798 : }
799 : }
800 0 : }
801 :
802 0 : pub(crate) fn get_secondary_tenant_shard(
803 0 : &self,
804 0 : tenant_shard_id: TenantShardId,
805 0 : ) -> Option<Arc<SecondaryTenant>> {
806 0 : let locked = self.tenants.read().unwrap();
807 :
808 0 : let peek_slot = tenant_map_peek_slot(&locked, &tenant_shard_id, TenantSlotPeekMode::Read)
809 0 : .ok()
810 0 : .flatten();
811 :
812 0 : match peek_slot {
813 0 : Some(TenantSlot::Secondary(s)) => Some(s.clone()),
814 0 : _ => None,
815 : }
816 0 : }
817 :
818 : /// Whether the `TenantManager` is responsible for the tenant shard
819 0 : pub(crate) fn manages_tenant_shard(&self, tenant_shard_id: TenantShardId) -> bool {
820 0 : let locked = self.tenants.read().unwrap();
821 :
822 0 : let peek_slot = tenant_map_peek_slot(&locked, &tenant_shard_id, TenantSlotPeekMode::Read)
823 0 : .ok()
824 0 : .flatten();
825 :
826 0 : peek_slot.is_some()
827 0 : }
828 :
829 : #[instrument(skip_all, fields(tenant_id=%tenant_shard_id.tenant_id, shard_id=%tenant_shard_id.shard_slug()))]
830 : pub(crate) async fn upsert_location(
831 : &self,
832 : tenant_shard_id: TenantShardId,
833 : new_location_config: LocationConf,
834 : flush: Option<Duration>,
835 : mut spawn_mode: SpawnMode,
836 : ctx: &RequestContext,
837 : ) -> Result<Option<Arc<TenantShard>>, UpsertLocationError> {
838 : debug_assert_current_span_has_tenant_id();
839 : info!("configuring tenant location to state {new_location_config:?}");
840 :
841 : enum FastPathModified {
842 : Attached(Arc<TenantShard>),
843 : Secondary(Arc<SecondaryTenant>),
844 : }
845 :
846 : // Special case fast-path for updates to existing slots: if our upsert is only updating configuration,
847 : // then we do not need to set the slot to InProgress, we can just call into the
848 : // existng tenant.
849 : let fast_path_taken = {
850 : let locked = self.tenants.read().unwrap();
851 : let peek_slot =
852 : tenant_map_peek_slot(&locked, &tenant_shard_id, TenantSlotPeekMode::Write)?;
853 : match (&new_location_config.mode, peek_slot) {
854 : (LocationMode::Attached(attach_conf), Some(TenantSlot::Attached(tenant))) => {
855 : match attach_conf.generation.cmp(&tenant.generation) {
856 : Ordering::Equal => {
857 : // A transition from Attached to Attached in the same generation, we may
858 : // take our fast path and just provide the updated configuration
859 : // to the tenant.
860 : tenant.set_new_location_config(
861 : AttachedTenantConf::try_from(
862 : self.conf,
863 : new_location_config.clone(),
864 : )
865 : .map_err(UpsertLocationError::BadRequest)?,
866 : );
867 :
868 : Some(FastPathModified::Attached(tenant.clone()))
869 : }
870 : Ordering::Less => {
871 : return Err(UpsertLocationError::BadRequest(anyhow::anyhow!(
872 : "Generation {:?} is less than existing {:?}",
873 : attach_conf.generation,
874 : tenant.generation
875 : )));
876 : }
877 : Ordering::Greater => {
878 : // Generation advanced, fall through to general case of replacing `Tenant` object
879 : None
880 : }
881 : }
882 : }
883 : (
884 : LocationMode::Secondary(secondary_conf),
885 : Some(TenantSlot::Secondary(secondary_tenant)),
886 : ) => {
887 : secondary_tenant.set_config(secondary_conf);
888 : secondary_tenant.set_tenant_conf(&new_location_config.tenant_conf);
889 : Some(FastPathModified::Secondary(secondary_tenant.clone()))
890 : }
891 : _ => {
892 : // Not an Attached->Attached transition, fall through to general case
893 : None
894 : }
895 : }
896 : };
897 :
898 : // Fast-path continued: having dropped out of the self.tenants lock, do the async
899 : // phase of writing config and/or waiting for flush, before returning.
900 : match fast_path_taken {
901 : Some(FastPathModified::Attached(tenant)) => {
902 : tenant
903 : .shard_identity
904 : .assert_equal(new_location_config.shard);
905 : TenantShard::persist_tenant_config(
906 : self.conf,
907 : &tenant_shard_id,
908 : &new_location_config,
909 : )
910 : .await
911 : .fatal_err("write tenant shard config");
912 :
913 : // Transition to AttachedStale means we may well hold a valid generation
914 : // still, and have been requested to go stale as part of a migration. If
915 : // the caller set `flush`, then flush to remote storage.
916 : if let LocationMode::Attached(AttachedLocationConfig {
917 : generation: _,
918 : attach_mode: AttachmentMode::Stale,
919 : }) = &new_location_config.mode
920 : {
921 : if let Some(flush_timeout) = flush {
922 : match tokio::time::timeout(flush_timeout, tenant.flush_remote()).await {
923 : Ok(Err(e)) => {
924 : return Err(UpsertLocationError::Flush(e));
925 : }
926 : Ok(Ok(_)) => return Ok(Some(tenant)),
927 : Err(_) => {
928 : tracing::warn!(
929 : timeout_ms = flush_timeout.as_millis(),
930 : "Timed out waiting for flush to remote storage, proceeding anyway."
931 : )
932 : }
933 : }
934 : }
935 : }
936 :
937 : return Ok(Some(tenant));
938 : }
939 : Some(FastPathModified::Secondary(secondary_tenant)) => {
940 : secondary_tenant
941 : .shard_identity
942 : .assert_equal(new_location_config.shard);
943 : TenantShard::persist_tenant_config(
944 : self.conf,
945 : &tenant_shard_id,
946 : &new_location_config,
947 : )
948 : .await
949 : .fatal_err("write tenant shard config");
950 :
951 : return Ok(None);
952 : }
953 : None => {
954 : // Proceed with the general case procedure, where we will shutdown & remove any existing
955 : // slot contents and replace with a fresh one
956 : }
957 : };
958 :
959 : // General case for upserts to TenantsMap, excluding the case above: we will substitute an
960 : // InProgress value to the slot while we make whatever changes are required. The state for
961 : // the tenant is inaccessible to the outside world while we are doing this, but that is sensible:
962 : // the state is ill-defined while we're in transition. Transitions are async, but fast: we do
963 : // not do significant I/O, and shutdowns should be prompt via cancellation tokens.
964 : let mut slot_guard = self
965 : .tenant_map_acquire_slot(&tenant_shard_id, TenantSlotAcquireMode::Any)
966 0 : .map_err(|e| match e {
967 : TenantSlotError::NotFound(_) => {
968 0 : unreachable!("Called with mode Any")
969 : }
970 0 : TenantSlotError::InProgress => UpsertLocationError::InProgress,
971 0 : TenantSlotError::MapState(s) => UpsertLocationError::Unavailable(s),
972 0 : })?;
973 :
974 : match slot_guard.get_old_value() {
975 : Some(TenantSlot::Attached(tenant)) => {
976 : tenant
977 : .shard_identity
978 : .assert_equal(new_location_config.shard);
979 :
980 : // The case where we keep a Tenant alive was covered above in the special case
981 : // for Attached->Attached transitions in the same generation. By this point,
982 : // if we see an attached tenant we know it will be discarded and should be
983 : // shut down.
984 : let (_guard, progress) = utils::completion::channel();
985 :
986 : match tenant.get_attach_mode() {
987 : AttachmentMode::Single | AttachmentMode::Multi => {
988 : // Before we leave our state as the presumed holder of the latest generation,
989 : // flush any outstanding deletions to reduce the risk of leaking objects.
990 : self.resources.deletion_queue_client.flush_advisory()
991 : }
992 : AttachmentMode::Stale => {
993 : // If we're stale there's not point trying to flush deletions
994 : }
995 : };
996 :
997 : info!("Shutting down attached tenant");
998 : match tenant.shutdown(progress, ShutdownMode::Hard).await {
999 : Ok(()) => {}
1000 : Err(barrier) => {
1001 : info!("Shutdown already in progress, waiting for it to complete");
1002 : barrier.wait().await;
1003 : }
1004 : }
1005 : slot_guard.drop_old_value().expect("We just shut it down");
1006 :
1007 : // Edge case: if we were called with SpawnMode::Create, but a Tenant already existed, then
1008 : // the caller thinks they're creating but the tenant already existed. We must switch to
1009 : // Eager mode so that when starting this Tenant we properly probe remote storage for timelines,
1010 : // rather than assuming it to be empty.
1011 : spawn_mode = SpawnMode::Eager;
1012 : }
1013 : Some(TenantSlot::Secondary(secondary_tenant)) => {
1014 : secondary_tenant
1015 : .shard_identity
1016 : .assert_equal(new_location_config.shard);
1017 :
1018 : info!("Shutting down secondary tenant");
1019 : secondary_tenant.shutdown().await;
1020 : }
1021 : Some(TenantSlot::InProgress(_)) => {
1022 : // This should never happen: acquire_slot should error out
1023 : // if the contents of a slot were InProgress.
1024 : return Err(UpsertLocationError::InternalError(anyhow::anyhow!(
1025 : "Acquired an InProgress slot, this is a bug."
1026 : )));
1027 : }
1028 : None => {
1029 : // Slot was vacant, nothing needs shutting down.
1030 : }
1031 : }
1032 :
1033 : let tenant_path = self.conf.tenant_path(&tenant_shard_id);
1034 : let timelines_path = self.conf.timelines_path(&tenant_shard_id);
1035 :
1036 : // Directory structure is the same for attached and secondary modes:
1037 : // create it if it doesn't exist. Timeline load/creation expects the
1038 : // timelines/ subdir to already exist.
1039 : //
1040 : // Does not need to be fsync'd because local storage is just a cache.
1041 : tokio::fs::create_dir_all(&timelines_path)
1042 : .await
1043 : .fatal_err("create timelines/ dir");
1044 :
1045 : // Before activating either secondary or attached mode, persist the
1046 : // configuration, so that on restart we will re-attach (or re-start
1047 : // secondary) on the tenant.
1048 : TenantShard::persist_tenant_config(self.conf, &tenant_shard_id, &new_location_config)
1049 : .await
1050 : .fatal_err("write tenant shard config");
1051 :
1052 : let new_slot = match &new_location_config.mode {
1053 : LocationMode::Secondary(secondary_config) => {
1054 : let shard_identity = new_location_config.shard;
1055 : TenantSlot::Secondary(SecondaryTenant::new(
1056 : tenant_shard_id,
1057 : shard_identity,
1058 : new_location_config.tenant_conf,
1059 : secondary_config,
1060 : ))
1061 : }
1062 : LocationMode::Attached(_attach_config) => {
1063 : let shard_identity = new_location_config.shard;
1064 :
1065 : // Testing hack: if we are configured with no control plane, then drop the generation
1066 : // from upserts. This enables creating generation-less tenants even though neon_local
1067 : // always uses generations when calling the location conf API.
1068 : let attached_conf = AttachedTenantConf::try_from(self.conf, new_location_config)
1069 : .map_err(UpsertLocationError::BadRequest)?;
1070 :
1071 : let tenant = tenant_spawn(
1072 : self.conf,
1073 : tenant_shard_id,
1074 : &tenant_path,
1075 : self.resources.clone(),
1076 : attached_conf,
1077 : shard_identity,
1078 : None,
1079 : spawn_mode,
1080 : ctx,
1081 : )
1082 0 : .map_err(|_: GlobalShutDown| {
1083 0 : UpsertLocationError::Unavailable(TenantMapError::ShuttingDown)
1084 0 : })?;
1085 :
1086 : TenantSlot::Attached(tenant)
1087 : }
1088 : };
1089 :
1090 : let attached_tenant = if let TenantSlot::Attached(tenant) = &new_slot {
1091 : Some(tenant.clone())
1092 : } else {
1093 : None
1094 : };
1095 :
1096 : match slot_guard.upsert(new_slot) {
1097 : Err(TenantSlotUpsertError::InternalError(e)) => {
1098 : Err(UpsertLocationError::InternalError(anyhow::anyhow!(e)))
1099 : }
1100 : Err(TenantSlotUpsertError::MapState(e)) => Err(UpsertLocationError::Unavailable(e)),
1101 : Err(TenantSlotUpsertError::ShuttingDown((new_slot, _completion))) => {
1102 : // If we just called tenant_spawn() on a new tenant, and can't insert it into our map, then
1103 : // we must not leak it: this would violate the invariant that after shutdown_all_tenants, all tenants
1104 : // are shutdown.
1105 : //
1106 : // We must shut it down inline here.
1107 : match new_slot {
1108 : TenantSlot::InProgress(_) => {
1109 : // Unreachable because we never insert an InProgress
1110 : unreachable!()
1111 : }
1112 : TenantSlot::Attached(tenant) => {
1113 : let (_guard, progress) = utils::completion::channel();
1114 : info!(
1115 : "Shutting down just-spawned tenant, because tenant manager is shut down"
1116 : );
1117 : match tenant.shutdown(progress, ShutdownMode::Hard).await {
1118 : Ok(()) => {
1119 : info!("Finished shutting down just-spawned tenant");
1120 : }
1121 : Err(barrier) => {
1122 : info!("Shutdown already in progress, waiting for it to complete");
1123 : barrier.wait().await;
1124 : }
1125 : }
1126 : }
1127 : TenantSlot::Secondary(secondary_tenant) => {
1128 : secondary_tenant.shutdown().await;
1129 : }
1130 : }
1131 :
1132 : Err(UpsertLocationError::Unavailable(
1133 : TenantMapError::ShuttingDown,
1134 : ))
1135 : }
1136 : Ok(()) => Ok(attached_tenant),
1137 : }
1138 : }
1139 :
1140 1 : fn tenant_map_acquire_slot(
1141 1 : &self,
1142 1 : tenant_shard_id: &TenantShardId,
1143 1 : mode: TenantSlotAcquireMode,
1144 1 : ) -> Result<SlotGuard, TenantSlotError> {
1145 : use TenantSlotAcquireMode::*;
1146 1 : METRICS.tenant_slot_writes.inc();
1147 :
1148 1 : let mut locked = self.tenants.write().unwrap();
1149 1 : let span = tracing::info_span!("acquire_slot", tenant_id=%tenant_shard_id.tenant_id, shard_id = %tenant_shard_id.shard_slug());
1150 1 : let _guard = span.enter();
1151 :
1152 1 : let m = match &mut *locked {
1153 0 : TenantsMap::Initializing => return Err(TenantMapError::StillInitializing.into()),
1154 0 : TenantsMap::ShuttingDown(_) => return Err(TenantMapError::ShuttingDown.into()),
1155 1 : TenantsMap::Open(m) => m,
1156 : };
1157 :
1158 : use std::collections::btree_map::Entry;
1159 :
1160 1 : let entry = m.entry(*tenant_shard_id);
1161 :
1162 1 : match entry {
1163 0 : Entry::Vacant(v) => match mode {
1164 : MustExist => {
1165 0 : tracing::debug!("Vacant && MustExist: return NotFound");
1166 0 : Err(TenantSlotError::NotFound(*tenant_shard_id))
1167 : }
1168 : _ => {
1169 0 : let (completion, barrier) = utils::completion::channel();
1170 0 : let inserting = TenantSlot::InProgress(barrier);
1171 0 : METRICS.slot_inserted(&inserting);
1172 0 : v.insert(inserting);
1173 0 : tracing::debug!("Vacant, inserted InProgress");
1174 0 : Ok(SlotGuard::new(
1175 0 : *tenant_shard_id,
1176 0 : None,
1177 0 : completion,
1178 0 : &self.tenants,
1179 0 : ))
1180 : }
1181 : },
1182 1 : Entry::Occupied(mut o) => {
1183 : // Apply mode-driven checks
1184 1 : match (o.get(), mode) {
1185 : (TenantSlot::InProgress(_), _) => {
1186 0 : tracing::debug!("Occupied, failing for InProgress");
1187 0 : Err(TenantSlotError::InProgress)
1188 : }
1189 : _ => {
1190 : // Happy case: the slot was not in any state that violated our mode
1191 1 : let (completion, barrier) = utils::completion::channel();
1192 1 : let in_progress = TenantSlot::InProgress(barrier);
1193 1 : METRICS.slot_inserted(&in_progress);
1194 1 : let old_value = o.insert(in_progress);
1195 1 : METRICS.slot_removed(&old_value);
1196 1 : tracing::debug!("Occupied, replaced with InProgress");
1197 1 : Ok(SlotGuard::new(
1198 1 : *tenant_shard_id,
1199 1 : Some(old_value),
1200 1 : completion,
1201 1 : &self.tenants,
1202 1 : ))
1203 : }
1204 : }
1205 : }
1206 : }
1207 1 : }
1208 :
1209 : /// Resetting a tenant is equivalent to detaching it, then attaching it again with the same
1210 : /// LocationConf that was last used to attach it. Optionally, the local file cache may be
1211 : /// dropped before re-attaching.
1212 : ///
1213 : /// This is not part of a tenant's normal lifecycle: it is used for debug/support, in situations
1214 : /// where an issue is identified that would go away with a restart of the tenant.
1215 : ///
1216 : /// This does not have any special "force" shutdown of a tenant: it relies on the tenant's tasks
1217 : /// to respect the cancellation tokens used in normal shutdown().
1218 : #[instrument(skip_all, fields(tenant_id=%tenant_shard_id.tenant_id, shard_id=%tenant_shard_id.shard_slug(), %drop_cache))]
1219 : pub(crate) async fn reset_tenant(
1220 : &self,
1221 : tenant_shard_id: TenantShardId,
1222 : drop_cache: bool,
1223 : ctx: &RequestContext,
1224 : ) -> anyhow::Result<()> {
1225 : let mut slot_guard =
1226 : self.tenant_map_acquire_slot(&tenant_shard_id, TenantSlotAcquireMode::Any)?;
1227 : let Some(old_slot) = slot_guard.get_old_value() else {
1228 : anyhow::bail!("Tenant not found when trying to reset");
1229 : };
1230 :
1231 : let Some(tenant) = old_slot.get_attached() else {
1232 : slot_guard.revert();
1233 : anyhow::bail!("Tenant is not in attached state");
1234 : };
1235 :
1236 : let (_guard, progress) = utils::completion::channel();
1237 : match tenant.shutdown(progress, ShutdownMode::Hard).await {
1238 : Ok(()) => {
1239 : slot_guard.drop_old_value()?;
1240 : }
1241 : Err(_barrier) => {
1242 : slot_guard.revert();
1243 : anyhow::bail!("Cannot reset Tenant, already shutting down");
1244 : }
1245 : }
1246 :
1247 : let tenant_path = self.conf.tenant_path(&tenant_shard_id);
1248 : let timelines_path = self.conf.timelines_path(&tenant_shard_id);
1249 : let config = TenantShard::load_tenant_config(self.conf, &tenant_shard_id)?;
1250 :
1251 : if drop_cache {
1252 : tracing::info!("Dropping local file cache");
1253 :
1254 : match tokio::fs::read_dir(&timelines_path).await {
1255 : Err(e) => {
1256 : tracing::warn!("Failed to list timelines while dropping cache: {}", e);
1257 : }
1258 : Ok(mut entries) => {
1259 : while let Some(entry) = entries.next_entry().await? {
1260 : tokio::fs::remove_dir_all(entry.path()).await?;
1261 : }
1262 : }
1263 : }
1264 : }
1265 :
1266 : let shard_identity = config.shard;
1267 : let tenant = tenant_spawn(
1268 : self.conf,
1269 : tenant_shard_id,
1270 : &tenant_path,
1271 : self.resources.clone(),
1272 : AttachedTenantConf::try_from(self.conf, config)?,
1273 : shard_identity,
1274 : None,
1275 : SpawnMode::Eager,
1276 : ctx,
1277 : )?;
1278 :
1279 : slot_guard.upsert(TenantSlot::Attached(tenant))?;
1280 :
1281 : Ok(())
1282 : }
1283 :
1284 0 : pub(crate) fn get_attached_active_tenant_shards(&self) -> Vec<Arc<TenantShard>> {
1285 0 : let locked = self.tenants.read().unwrap();
1286 0 : match &*locked {
1287 0 : TenantsMap::Initializing => Vec::new(),
1288 0 : TenantsMap::Open(map) | TenantsMap::ShuttingDown(map) => map
1289 0 : .values()
1290 0 : .filter_map(|slot| {
1291 0 : slot.get_attached()
1292 0 : .and_then(|t| if t.is_active() { Some(t.clone()) } else { None })
1293 0 : })
1294 0 : .collect(),
1295 : }
1296 0 : }
1297 : // Do some synchronous work for all tenant slots in Secondary state. The provided
1298 : // callback should be small and fast, as it will be called inside the global
1299 : // TenantsMap lock.
1300 0 : pub(crate) fn foreach_secondary_tenants<F>(&self, mut func: F)
1301 0 : where
1302 0 : // TODO: let the callback return a hint to drop out of the loop early
1303 0 : F: FnMut(&TenantShardId, &Arc<SecondaryTenant>),
1304 : {
1305 0 : let locked = self.tenants.read().unwrap();
1306 :
1307 0 : let map = match &*locked {
1308 0 : TenantsMap::Initializing | TenantsMap::ShuttingDown(_) => return,
1309 0 : TenantsMap::Open(m) => m,
1310 : };
1311 :
1312 0 : for (tenant_id, slot) in map {
1313 0 : if let TenantSlot::Secondary(state) = slot {
1314 : // Only expose secondary tenants that are not currently shutting down
1315 0 : if !state.cancel.is_cancelled() {
1316 0 : func(tenant_id, state)
1317 0 : }
1318 0 : }
1319 : }
1320 0 : }
1321 :
1322 : /// Total list of all tenant slots: this includes attached, secondary, and InProgress.
1323 0 : pub(crate) fn list(&self) -> Vec<(TenantShardId, TenantSlot)> {
1324 0 : let locked = self.tenants.read().unwrap();
1325 0 : match &*locked {
1326 0 : TenantsMap::Initializing => Vec::new(),
1327 0 : TenantsMap::Open(map) | TenantsMap::ShuttingDown(map) => {
1328 0 : map.iter().map(|(k, v)| (*k, v.clone())).collect()
1329 : }
1330 : }
1331 0 : }
1332 :
1333 0 : pub(crate) fn get(&self, tenant_shard_id: TenantShardId) -> Option<TenantSlot> {
1334 0 : let locked = self.tenants.read().unwrap();
1335 0 : match &*locked {
1336 0 : TenantsMap::Initializing => None,
1337 0 : TenantsMap::Open(map) | TenantsMap::ShuttingDown(map) => {
1338 0 : map.get(&tenant_shard_id).cloned()
1339 : }
1340 : }
1341 0 : }
1342 :
1343 : /// If a tenant is attached, detach it. Then remove its data from remote storage.
1344 : ///
1345 : /// A tenant is considered deleted once it is gone from remote storage. It is the caller's
1346 : /// responsibility to avoid trying to attach the tenant again or use it any way once deletion
1347 : /// has started: this operation is not atomic, and must be retried until it succeeds.
1348 : ///
1349 : /// As a special case, if an unsharded tenant ID is given for a sharded tenant, it will remove
1350 : /// all tenant shards in remote storage (removing all paths with the tenant prefix). The storage
1351 : /// controller uses this to purge all remote tenant data, including any stale parent shards that
1352 : /// may remain after splits. Ideally, this special case would be handled elsewhere. See:
1353 : /// <https://github.com/neondatabase/neon/pull/9394>.
1354 0 : pub(crate) async fn delete_tenant(
1355 0 : &self,
1356 0 : tenant_shard_id: TenantShardId,
1357 0 : ) -> Result<(), DeleteTenantError> {
1358 0 : super::span::debug_assert_current_span_has_tenant_id();
1359 :
1360 0 : async fn delete_local(
1361 0 : conf: &PageServerConf,
1362 0 : background_purges: &BackgroundPurges,
1363 0 : tenant_shard_id: &TenantShardId,
1364 0 : ) -> anyhow::Result<()> {
1365 0 : let local_tenant_directory = conf.tenant_path(tenant_shard_id);
1366 0 : let tmp_dir = safe_rename_tenant_dir(&local_tenant_directory)
1367 0 : .await
1368 0 : .with_context(|| {
1369 0 : format!("local tenant directory {local_tenant_directory:?} rename")
1370 0 : })?;
1371 0 : background_purges.spawn(tmp_dir);
1372 0 : Ok(())
1373 0 : }
1374 :
1375 0 : let slot_guard =
1376 0 : self.tenant_map_acquire_slot(&tenant_shard_id, TenantSlotAcquireMode::Any)?;
1377 0 : match &slot_guard.old_value {
1378 0 : Some(TenantSlot::Attached(tenant)) => {
1379 : // Legacy deletion flow: the tenant remains attached, goes to Stopping state, and
1380 : // deletion will be resumed across restarts.
1381 0 : let tenant = tenant.clone();
1382 0 : let (_guard, progress) = utils::completion::channel();
1383 0 : match tenant.shutdown(progress, ShutdownMode::Hard).await {
1384 0 : Ok(()) => {}
1385 0 : Err(barrier) => {
1386 0 : info!("Shutdown already in progress, waiting for it to complete");
1387 0 : barrier.wait().await;
1388 : }
1389 : }
1390 0 : delete_local(self.conf, &self.background_purges, &tenant_shard_id).await?;
1391 : }
1392 0 : Some(TenantSlot::Secondary(secondary_tenant)) => {
1393 0 : secondary_tenant.shutdown().await;
1394 :
1395 0 : delete_local(self.conf, &self.background_purges, &tenant_shard_id).await?;
1396 : }
1397 0 : Some(TenantSlot::InProgress(_)) => unreachable!(),
1398 0 : None => {}
1399 : };
1400 :
1401 : // Fall through: local state for this tenant is no longer present, proceed with remote delete.
1402 : // - We use a retry wrapper here so that common transient S3 errors (e.g. 503, 429) do not result
1403 : // in 500 responses to delete requests.
1404 : // - We keep the `SlotGuard` during this I/O, so that if a concurrent delete request comes in, it will
1405 : // 503/retry, rather than kicking off a wasteful concurrent deletion.
1406 : // NB: this also deletes partial prefixes, i.e. a <tenant_id> path will delete all
1407 : // <tenant_id>_<shard_id>/* objects. See method comment for why.
1408 0 : backoff::retry(
1409 0 : || async move {
1410 0 : self.resources
1411 0 : .remote_storage
1412 0 : .delete_prefix(&remote_tenant_path(&tenant_shard_id), &self.cancel)
1413 0 : .await
1414 0 : },
1415 : |_| false, // backoff::retry handles cancellation
1416 : 1,
1417 : 3,
1418 0 : &format!("delete_tenant[tenant_shard_id={tenant_shard_id}]"),
1419 0 : &self.cancel,
1420 : )
1421 0 : .await
1422 0 : .unwrap_or(Err(TimeoutOrCancel::Cancel.into()))
1423 0 : .map_err(|err| {
1424 0 : if TimeoutOrCancel::caused_by_cancel(&err) {
1425 0 : return DeleteTenantError::Cancelled;
1426 0 : }
1427 0 : DeleteTenantError::Other(err)
1428 0 : })
1429 0 : }
1430 :
1431 : #[instrument(skip_all, fields(tenant_id=%tenant.get_tenant_shard_id().tenant_id, shard_id=%tenant.get_tenant_shard_id().shard_slug(), new_shard_count=%new_shard_count.literal()))]
1432 : pub(crate) async fn shard_split(
1433 : &self,
1434 : tenant: Arc<TenantShard>,
1435 : new_shard_count: ShardCount,
1436 : new_stripe_size: Option<ShardStripeSize>,
1437 : ctx: &RequestContext,
1438 : ) -> anyhow::Result<Vec<TenantShardId>> {
1439 : let tenant_shard_id = *tenant.get_tenant_shard_id();
1440 : let r = self
1441 : .do_shard_split(tenant, new_shard_count, new_stripe_size, ctx)
1442 : .await;
1443 : if r.is_err() {
1444 : // Shard splitting might have left the original shard in a partially shut down state (it
1445 : // stops the shard's remote timeline client). Reset it to ensure we leave things in
1446 : // a working state.
1447 : if self.get(tenant_shard_id).is_some() {
1448 : tracing::warn!("Resetting after shard split failure");
1449 : if let Err(e) = self.reset_tenant(tenant_shard_id, false, ctx).await {
1450 : // Log this error because our return value will still be the original error, not this one. This is
1451 : // a severe error: if this happens, we might be leaving behind a tenant that is not fully functional
1452 : // (e.g. has uploads disabled). We can't do anything else: if reset fails then shutting the tenant down or
1453 : // setting it broken probably won't help either.
1454 : tracing::error!("Failed to reset: {e}");
1455 : }
1456 : }
1457 : }
1458 :
1459 : r
1460 : }
1461 :
1462 0 : pub(crate) async fn do_shard_split(
1463 0 : &self,
1464 0 : tenant: Arc<TenantShard>,
1465 0 : new_shard_count: ShardCount,
1466 0 : new_stripe_size: Option<ShardStripeSize>,
1467 0 : ctx: &RequestContext,
1468 0 : ) -> anyhow::Result<Vec<TenantShardId>> {
1469 0 : let tenant_shard_id = *tenant.get_tenant_shard_id();
1470 :
1471 : // Validate the incoming request
1472 0 : if new_shard_count.count() <= tenant_shard_id.shard_count.count() {
1473 0 : anyhow::bail!("Requested shard count is not an increase");
1474 0 : }
1475 0 : let expansion_factor = new_shard_count.count() / tenant_shard_id.shard_count.count();
1476 0 : if !expansion_factor.is_power_of_two() {
1477 0 : anyhow::bail!("Requested split is not a power of two");
1478 0 : }
1479 :
1480 0 : if let Some(new_stripe_size) = new_stripe_size {
1481 0 : if tenant.get_shard_stripe_size() != new_stripe_size
1482 0 : && tenant_shard_id.shard_count.count() > 1
1483 : {
1484 : // This tenant already has multiple shards, it is illegal to try and change its stripe size
1485 0 : anyhow::bail!(
1486 0 : "Shard stripe size may not be modified once tenant has multiple shards"
1487 : );
1488 0 : }
1489 0 : }
1490 :
1491 : // Plan: identify what the new child shards will be
1492 0 : let child_shards = tenant_shard_id.split(new_shard_count);
1493 0 : tracing::info!(
1494 0 : "Shard {} splits into: {}",
1495 0 : tenant_shard_id.to_index(),
1496 0 : child_shards
1497 0 : .iter()
1498 0 : .map(|id| format!("{}", id.to_index()))
1499 0 : .join(",")
1500 : );
1501 :
1502 0 : fail::fail_point!("shard-split-pre-prepare", |_| Err(anyhow::anyhow!(
1503 0 : "failpoint"
1504 : )));
1505 :
1506 0 : let parent_shard_identity = tenant.shard_identity;
1507 0 : let parent_tenant_conf = tenant.get_tenant_conf();
1508 0 : let parent_generation = tenant.generation;
1509 :
1510 : // Phase 1: Write out child shards' remote index files, in the parent tenant's current generation
1511 0 : if let Err(e) = tenant.split_prepare(&child_shards).await {
1512 : // If [`Tenant::split_prepare`] fails, we must reload the tenant, because it might
1513 : // have been left in a partially-shut-down state.
1514 0 : tracing::warn!("Failed to prepare for split: {e}, reloading Tenant before returning");
1515 0 : return Err(e);
1516 0 : }
1517 :
1518 0 : fail::fail_point!("shard-split-post-prepare", |_| Err(anyhow::anyhow!(
1519 0 : "failpoint"
1520 : )));
1521 :
1522 0 : self.resources.deletion_queue_client.flush_advisory();
1523 :
1524 : // Phase 2: Put the parent shard to InProgress and grab a reference to the parent Tenant
1525 0 : drop(tenant);
1526 0 : let mut parent_slot_guard =
1527 0 : self.tenant_map_acquire_slot(&tenant_shard_id, TenantSlotAcquireMode::Any)?;
1528 0 : let parent = match parent_slot_guard.get_old_value() {
1529 0 : Some(TenantSlot::Attached(t)) => t,
1530 0 : Some(TenantSlot::Secondary(_)) => anyhow::bail!("Tenant location in secondary mode"),
1531 : Some(TenantSlot::InProgress(_)) => {
1532 : // tenant_map_acquire_slot never returns InProgress, if a slot was InProgress
1533 : // it would return an error.
1534 0 : unreachable!()
1535 : }
1536 : None => {
1537 : // We don't actually need the parent shard to still be attached to do our work, but it's
1538 : // a weird enough situation that the caller probably didn't want us to continue working
1539 : // if they had detached the tenant they requested the split on.
1540 0 : anyhow::bail!("Detached parent shard in the middle of split!")
1541 : }
1542 : };
1543 0 : fail::fail_point!("shard-split-pre-hardlink", |_| Err(anyhow::anyhow!(
1544 0 : "failpoint"
1545 : )));
1546 : // Optimization: hardlink layers from the parent into the children, so that they don't have to
1547 : // re-download & duplicate the data referenced in their initial IndexPart
1548 0 : self.shard_split_hardlink(parent, child_shards.clone())
1549 0 : .await?;
1550 0 : fail::fail_point!("shard-split-post-hardlink", |_| Err(anyhow::anyhow!(
1551 0 : "failpoint"
1552 : )));
1553 :
1554 : // Take a snapshot of where the parent's WAL ingest had got to: we will wait for
1555 : // child shards to reach this point.
1556 0 : let mut target_lsns = HashMap::new();
1557 0 : for timeline in parent.timelines.lock().unwrap().clone().values() {
1558 0 : target_lsns.insert(timeline.timeline_id, timeline.get_last_record_lsn());
1559 0 : }
1560 :
1561 : // TODO: we should have the parent shard stop its WAL ingest here, it's a waste of resources
1562 : // and could slow down the children trying to catch up.
1563 :
1564 : // Phase 3: Spawn the child shards
1565 0 : for child_shard in &child_shards {
1566 0 : let mut child_shard_identity = parent_shard_identity;
1567 0 : if let Some(new_stripe_size) = new_stripe_size {
1568 0 : child_shard_identity.stripe_size = new_stripe_size;
1569 0 : }
1570 0 : child_shard_identity.count = child_shard.shard_count;
1571 0 : child_shard_identity.number = child_shard.shard_number;
1572 :
1573 0 : let child_location_conf = LocationConf {
1574 0 : mode: LocationMode::Attached(AttachedLocationConfig {
1575 0 : generation: parent_generation,
1576 0 : attach_mode: AttachmentMode::Single,
1577 0 : }),
1578 0 : shard: child_shard_identity,
1579 0 : tenant_conf: parent_tenant_conf.clone(),
1580 0 : };
1581 :
1582 0 : self.upsert_location(
1583 0 : *child_shard,
1584 0 : child_location_conf,
1585 0 : None,
1586 0 : SpawnMode::Eager,
1587 0 : ctx,
1588 0 : )
1589 0 : .await?;
1590 : }
1591 :
1592 0 : fail::fail_point!("shard-split-post-child-conf", |_| Err(anyhow::anyhow!(
1593 0 : "failpoint"
1594 : )));
1595 :
1596 : // Phase 4: wait for child chards WAL ingest to catch up to target LSN
1597 0 : for child_shard_id in &child_shards {
1598 0 : let child_shard_id = *child_shard_id;
1599 0 : let child_shard = {
1600 0 : let locked = self.tenants.read().unwrap();
1601 0 : let peek_slot =
1602 0 : tenant_map_peek_slot(&locked, &child_shard_id, TenantSlotPeekMode::Read)?;
1603 0 : peek_slot.and_then(|s| s.get_attached()).cloned()
1604 : };
1605 0 : if let Some(t) = child_shard {
1606 : // Wait for the child shard to become active: this should be very quick because it only
1607 : // has to download the index_part that we just uploaded when creating it.
1608 0 : if let Err(e) = t.wait_to_become_active(ACTIVE_TENANT_TIMEOUT).await {
1609 : // This is not fatal: we have durably created the child shard. It just makes the
1610 : // split operation less seamless for clients, as we will may detach the parent
1611 : // shard before the child shards are fully ready to serve requests.
1612 0 : tracing::warn!("Failed to wait for shard {child_shard_id} to activate: {e}");
1613 0 : continue;
1614 0 : }
1615 :
1616 0 : let timelines = t.timelines.lock().unwrap().clone();
1617 0 : for timeline in timelines.values() {
1618 0 : let Some(target_lsn) = target_lsns.get(&timeline.timeline_id) else {
1619 0 : continue;
1620 : };
1621 :
1622 0 : tracing::info!(
1623 0 : "Waiting for child shard {}/{} to reach target lsn {}...",
1624 : child_shard_id,
1625 0 : timeline.timeline_id,
1626 : target_lsn
1627 : );
1628 :
1629 0 : fail::fail_point!("shard-split-lsn-wait", |_| Err(anyhow::anyhow!(
1630 0 : "failpoint"
1631 : )));
1632 0 : if let Err(e) = timeline
1633 0 : .wait_lsn(
1634 0 : *target_lsn,
1635 0 : crate::tenant::timeline::WaitLsnWaiter::Tenant,
1636 0 : crate::tenant::timeline::WaitLsnTimeout::Default,
1637 0 : ctx,
1638 0 : )
1639 0 : .await
1640 : {
1641 : // Failure here might mean shutdown, in any case this part is an optimization
1642 : // and we shouldn't hold up the split operation.
1643 0 : tracing::warn!(
1644 0 : "Failed to wait for timeline {} to reach lsn {target_lsn}: {e}",
1645 0 : timeline.timeline_id
1646 : );
1647 : } else {
1648 0 : tracing::info!(
1649 0 : "Child shard {}/{} reached target lsn {}",
1650 : child_shard_id,
1651 0 : timeline.timeline_id,
1652 : target_lsn
1653 : );
1654 : }
1655 : }
1656 0 : }
1657 : }
1658 :
1659 : // Phase 5: Shut down the parent shard. We leave it on disk in case the split fails and we
1660 : // have to roll back to the parent shard, avoiding a cold start. It will be cleaned up once
1661 : // the storage controller commits the split, or if all else fails, on the next restart.
1662 : //
1663 : // TODO: We don't flush the ephemeral layer here, because the split is likely to succeed and
1664 : // catching up the parent should be reasonably quick. Consider using FreezeAndFlush instead.
1665 0 : let (_guard, progress) = completion::channel();
1666 0 : match parent.shutdown(progress, ShutdownMode::Hard).await {
1667 0 : Ok(()) => {}
1668 0 : Err(other) => {
1669 0 : other.wait().await;
1670 : }
1671 : }
1672 :
1673 0 : fail::fail_point!("shard-split-pre-finish", |_| Err(anyhow::anyhow!(
1674 0 : "failpoint"
1675 : )));
1676 :
1677 0 : parent_slot_guard.drop_old_value()?;
1678 :
1679 : // Phase 6: Release the InProgress on the parent shard
1680 0 : drop(parent_slot_guard);
1681 :
1682 0 : utils::pausable_failpoint!("shard-split-post-finish-pause");
1683 :
1684 0 : Ok(child_shards)
1685 0 : }
1686 :
1687 : /// Part of [`Self::shard_split`]: hard link parent shard layers into child shards, as an optimization
1688 : /// to avoid the children downloading them again.
1689 : ///
1690 : /// For each resident layer in the parent shard, we will hard link it into all of the child shards.
1691 0 : async fn shard_split_hardlink(
1692 0 : &self,
1693 0 : parent_shard: &TenantShard,
1694 0 : child_shards: Vec<TenantShardId>,
1695 0 : ) -> anyhow::Result<()> {
1696 0 : debug_assert_current_span_has_tenant_id();
1697 :
1698 0 : let parent_path = self.conf.tenant_path(parent_shard.get_tenant_shard_id());
1699 0 : let (parent_timelines, parent_layers) = {
1700 0 : let mut parent_layers = Vec::new();
1701 0 : let timelines = parent_shard.timelines.lock().unwrap().clone();
1702 0 : let parent_timelines = timelines.keys().cloned().collect::<Vec<_>>();
1703 0 : for timeline in timelines.values() {
1704 0 : tracing::info!(timeline_id=%timeline.timeline_id, "Loading list of layers to hardlink");
1705 0 : let layers = timeline
1706 0 : .layers
1707 0 : .read(LayerManagerLockHolder::GetLayerMapInfo)
1708 0 : .await;
1709 :
1710 0 : for layer in layers.likely_resident_layers() {
1711 0 : let relative_path = layer
1712 0 : .local_path()
1713 0 : .strip_prefix(&parent_path)
1714 0 : .context("Removing prefix from parent layer path")?;
1715 0 : parent_layers.push(relative_path.to_owned());
1716 : }
1717 : }
1718 :
1719 0 : if parent_layers.is_empty() {
1720 0 : tracing::info!("Ancestor shard has no resident layer to hard link");
1721 0 : }
1722 :
1723 0 : (parent_timelines, parent_layers)
1724 : };
1725 :
1726 0 : let mut child_prefixes = Vec::new();
1727 0 : let mut create_dirs = Vec::new();
1728 :
1729 0 : for child in child_shards {
1730 0 : let child_prefix = self.conf.tenant_path(&child);
1731 0 : create_dirs.push(child_prefix.clone());
1732 0 : create_dirs.extend(
1733 0 : parent_timelines
1734 0 : .iter()
1735 0 : .map(|t| self.conf.timeline_path(&child, t)),
1736 : );
1737 :
1738 0 : child_prefixes.push(child_prefix);
1739 : }
1740 :
1741 : // Since we will do a large number of small filesystem metadata operations, batch them into
1742 : // spawn_blocking calls rather than doing each one as a tokio::fs round-trip.
1743 0 : let span = tracing::Span::current();
1744 0 : let jh = tokio::task::spawn_blocking(move || -> anyhow::Result<usize> {
1745 : // Run this synchronous code in the same log context as the outer function that spawned it.
1746 0 : let _span = span.enter();
1747 :
1748 0 : tracing::info!("Creating {} directories", create_dirs.len());
1749 0 : for dir in &create_dirs {
1750 0 : if let Err(e) = std::fs::create_dir_all(dir) {
1751 : // Ignore AlreadyExists errors, drop out on all other errors
1752 0 : match e.kind() {
1753 0 : std::io::ErrorKind::AlreadyExists => {}
1754 : _ => {
1755 0 : return Err(anyhow::anyhow!(e).context(format!("Creating {dir}")));
1756 : }
1757 : }
1758 0 : }
1759 : }
1760 :
1761 0 : for child_prefix in child_prefixes {
1762 0 : tracing::info!(
1763 0 : "Hard-linking {} parent layers into child path {}",
1764 0 : parent_layers.len(),
1765 : child_prefix
1766 : );
1767 0 : for relative_layer in &parent_layers {
1768 0 : let parent_path = parent_path.join(relative_layer);
1769 0 : let child_path = child_prefix.join(relative_layer);
1770 0 : if let Err(e) = std::fs::hard_link(&parent_path, &child_path) {
1771 0 : match e.kind() {
1772 0 : std::io::ErrorKind::AlreadyExists => {}
1773 : std::io::ErrorKind::NotFound => {
1774 0 : tracing::info!(
1775 0 : "Layer {} not found during hard-linking, evicted during split?",
1776 : relative_layer
1777 : );
1778 : }
1779 : _ => {
1780 0 : return Err(anyhow::anyhow!(e).context(format!(
1781 0 : "Hard linking {relative_layer} into {child_prefix}"
1782 0 : )));
1783 : }
1784 : }
1785 0 : }
1786 : }
1787 : }
1788 :
1789 : // Durability is not required for correctness, but if we crashed during split and
1790 : // then came restarted with empty timeline dirs, it would be very inefficient to
1791 : // re-populate from remote storage.
1792 0 : tracing::info!("fsyncing {} directories", create_dirs.len());
1793 0 : for dir in create_dirs {
1794 0 : if let Err(e) = crashsafe::fsync(&dir) {
1795 : // Something removed a newly created timeline dir out from underneath us? Extremely
1796 : // unexpected, but not worth panic'ing over as this whole function is just an
1797 : // optimization.
1798 0 : tracing::warn!("Failed to fsync directory {dir}: {e}")
1799 0 : }
1800 : }
1801 :
1802 0 : Ok(parent_layers.len())
1803 0 : });
1804 :
1805 0 : match jh.await {
1806 0 : Ok(Ok(layer_count)) => {
1807 0 : tracing::info!(count = layer_count, "Hard linked layers into child shards");
1808 : }
1809 0 : Ok(Err(e)) => {
1810 : // This is an optimization, so we tolerate failure.
1811 0 : tracing::warn!("Error hard-linking layers, proceeding anyway: {e}")
1812 : }
1813 0 : Err(e) => {
1814 : // This is something totally unexpected like a panic, so bail out.
1815 0 : anyhow::bail!("Error joining hard linking task: {e}");
1816 : }
1817 : }
1818 :
1819 0 : Ok(())
1820 0 : }
1821 :
1822 : ///
1823 : /// Shut down all tenants. This runs as part of pageserver shutdown.
1824 : ///
1825 : /// NB: We leave the tenants in the map, so that they remain accessible through
1826 : /// the management API until we shut it down. If we removed the shut-down tenants
1827 : /// from the tenants map, the management API would return 404 for these tenants,
1828 : /// because TenantsMap::get() now returns `None`.
1829 : /// That could be easily misinterpreted by control plane, the consumer of the
1830 : /// management API. For example, it could attach the tenant on a different pageserver.
1831 : /// We would then be in split-brain once this pageserver restarts.
1832 : #[instrument(skip_all)]
1833 : pub(crate) async fn shutdown(&self) {
1834 : self.cancel.cancel();
1835 :
1836 : self.shutdown_all_tenants0().await
1837 : }
1838 :
1839 1 : async fn shutdown_all_tenants0(&self) {
1840 1 : let mut join_set = JoinSet::new();
1841 :
1842 : #[cfg(all(debug_assertions, not(test)))]
1843 : {
1844 : // Check that our metrics properly tracked the size of the tenants map. This is a convenient location to check,
1845 : // as it happens implicitly at the end of tests etc.
1846 0 : let m = self.tenants.read().unwrap();
1847 0 : debug_assert_eq!(METRICS.slots_total(), m.len() as u64);
1848 : }
1849 :
1850 : // Atomically, 1. create the shutdown tasks and 2. prevent creation of new tenants.
1851 1 : let (total_in_progress, total_attached) = {
1852 1 : let mut m = self.tenants.write().unwrap();
1853 1 : match &mut *m {
1854 : TenantsMap::Initializing => {
1855 0 : *m = TenantsMap::ShuttingDown(BTreeMap::default());
1856 0 : info!("tenants map is empty");
1857 0 : return;
1858 : }
1859 1 : TenantsMap::Open(tenants) => {
1860 1 : let mut shutdown_state = BTreeMap::new();
1861 1 : let mut total_in_progress = 0;
1862 1 : let mut total_attached = 0;
1863 :
1864 1 : for (tenant_shard_id, v) in std::mem::take(tenants).into_iter() {
1865 1 : match v {
1866 0 : TenantSlot::Attached(t) => {
1867 0 : shutdown_state
1868 0 : .insert(tenant_shard_id, TenantSlot::Attached(t.clone()));
1869 0 : join_set.spawn(
1870 0 : async move {
1871 0 : let res = {
1872 0 : let (_guard, shutdown_progress) = completion::channel();
1873 0 : t.shutdown(shutdown_progress, ShutdownMode::FreezeAndFlush).await
1874 : };
1875 :
1876 0 : if let Err(other_progress) = res {
1877 : // join the another shutdown in progress
1878 0 : other_progress.wait().await;
1879 0 : }
1880 :
1881 : // we cannot afford per tenant logging here, because if s3 is degraded, we are
1882 : // going to log too many lines
1883 0 : debug!("tenant successfully stopped");
1884 0 : }
1885 0 : .instrument(info_span!("shutdown", tenant_id=%tenant_shard_id.tenant_id, shard_id=%tenant_shard_id.shard_slug())),
1886 : );
1887 :
1888 0 : total_attached += 1;
1889 : }
1890 0 : TenantSlot::Secondary(state) => {
1891 0 : // We don't need to wait for this individually per-tenant: the
1892 0 : // downloader task will be waited on eventually, this cancel
1893 0 : // is just to encourage it to drop out if it is doing work
1894 0 : // for this tenant right now.
1895 0 : state.cancel.cancel();
1896 0 :
1897 0 : shutdown_state
1898 0 : .insert(tenant_shard_id, TenantSlot::Secondary(state));
1899 0 : }
1900 1 : TenantSlot::InProgress(notify) => {
1901 : // InProgress tenants are not visible in TenantsMap::ShuttingDown: we will
1902 : // wait for their notifications to fire in this function.
1903 1 : join_set.spawn(async move {
1904 1 : notify.wait().await;
1905 1 : });
1906 :
1907 1 : total_in_progress += 1;
1908 : }
1909 : }
1910 : }
1911 1 : *m = TenantsMap::ShuttingDown(shutdown_state);
1912 1 : (total_in_progress, total_attached)
1913 : }
1914 : TenantsMap::ShuttingDown(_) => {
1915 0 : error!(
1916 0 : "already shutting down, this function isn't supposed to be called more than once"
1917 : );
1918 0 : return;
1919 : }
1920 : }
1921 : };
1922 :
1923 1 : let started_at = std::time::Instant::now();
1924 :
1925 1 : info!(
1926 0 : "Waiting for {} InProgress tenants and {} Attached tenants to shut down",
1927 : total_in_progress, total_attached
1928 : );
1929 :
1930 1 : let total = join_set.len();
1931 1 : let mut panicked = 0;
1932 1 : let mut buffering = true;
1933 : const BUFFER_FOR: std::time::Duration = std::time::Duration::from_millis(500);
1934 1 : let mut buffered = std::pin::pin!(tokio::time::sleep(BUFFER_FOR));
1935 :
1936 3 : while !join_set.is_empty() {
1937 2 : tokio::select! {
1938 2 : Some(joined) = join_set.join_next() => {
1939 0 : match joined {
1940 1 : Ok(()) => {},
1941 0 : Err(join_error) if join_error.is_cancelled() => {
1942 0 : unreachable!("we are not cancelling any of the tasks");
1943 : }
1944 0 : Err(join_error) if join_error.is_panic() => {
1945 0 : // cannot really do anything, as this panic is likely a bug
1946 0 : panicked += 1;
1947 0 : }
1948 0 : Err(join_error) => {
1949 0 : warn!("unknown kind of JoinError: {join_error}");
1950 : }
1951 : }
1952 1 : if !buffering {
1953 1 : // buffer so that every 500ms since the first update (or starting) we'll log
1954 1 : // how far away we are; this is because we will get SIGKILL'd at 10s, and we
1955 1 : // are not able to log *then*.
1956 1 : buffering = true;
1957 1 : buffered.as_mut().reset(tokio::time::Instant::now() + BUFFER_FOR);
1958 1 : }
1959 : },
1960 2 : _ = &mut buffered, if buffering => {
1961 1 : buffering = false;
1962 1 : info!(remaining = join_set.len(), total, elapsed_ms = started_at.elapsed().as_millis(), "waiting for tenants to shutdown");
1963 : }
1964 : }
1965 : }
1966 :
1967 1 : if panicked > 0 {
1968 0 : warn!(
1969 : panicked,
1970 0 : total, "observed panicks while shutting down tenants"
1971 : );
1972 1 : }
1973 :
1974 : // caller will log how long we took
1975 1 : }
1976 :
1977 : /// Detaches a tenant, and removes its local files asynchronously.
1978 : ///
1979 : /// File removal is idempotent: even if the tenant has already been removed, this will still
1980 : /// remove any local files. This is used during shard splits, where we leave the parent shard's
1981 : /// files around in case we have to roll back the split.
1982 0 : pub(crate) async fn detach_tenant(
1983 0 : &self,
1984 0 : conf: &'static PageServerConf,
1985 0 : tenant_shard_id: TenantShardId,
1986 0 : deletion_queue_client: &DeletionQueueClient,
1987 0 : ) -> Result<(), TenantStateError> {
1988 0 : if let Some(tmp_path) = self
1989 0 : .detach_tenant0(conf, tenant_shard_id, deletion_queue_client)
1990 0 : .await?
1991 0 : {
1992 0 : self.background_purges.spawn(tmp_path);
1993 0 : }
1994 :
1995 0 : Ok(())
1996 0 : }
1997 :
1998 : /// Detaches a tenant. This renames the tenant directory to a temporary path and returns it,
1999 : /// allowing the caller to delete it asynchronously. Returns None if the dir is already removed.
2000 0 : async fn detach_tenant0(
2001 0 : &self,
2002 0 : conf: &'static PageServerConf,
2003 0 : tenant_shard_id: TenantShardId,
2004 0 : deletion_queue_client: &DeletionQueueClient,
2005 0 : ) -> Result<Option<Utf8PathBuf>, TenantStateError> {
2006 0 : let tenant_dir_rename_operation = |tenant_id_to_clean: TenantShardId| async move {
2007 0 : let local_tenant_directory = conf.tenant_path(&tenant_id_to_clean);
2008 0 : if !tokio::fs::try_exists(&local_tenant_directory).await? {
2009 : // If the tenant directory doesn't exist, it's already cleaned up.
2010 0 : return Ok(None);
2011 0 : }
2012 0 : safe_rename_tenant_dir(&local_tenant_directory)
2013 0 : .await
2014 0 : .with_context(|| {
2015 0 : format!("local tenant directory {local_tenant_directory:?} rename")
2016 0 : })
2017 0 : .map(Some)
2018 0 : };
2019 :
2020 0 : let mut removal_result = self
2021 0 : .remove_tenant_from_memory(
2022 0 : tenant_shard_id,
2023 0 : tenant_dir_rename_operation(tenant_shard_id),
2024 0 : )
2025 0 : .await;
2026 :
2027 : // If the tenant was not found, it was likely already removed. Attempt to remove the tenant
2028 : // directory on disk anyway. For example, during shard splits, we shut down and remove the
2029 : // parent shard, but leave its directory on disk in case we have to roll back the split.
2030 : //
2031 : // TODO: it would be better to leave the parent shard attached until the split is committed.
2032 : // This will be needed by the gRPC page service too, such that a compute can continue to
2033 : // read from the parent shard until it's notified about the new child shards. See:
2034 : // <https://github.com/neondatabase/neon/issues/11728>.
2035 0 : if let Err(TenantStateError::SlotError(TenantSlotError::NotFound(_))) = removal_result {
2036 0 : removal_result = tenant_dir_rename_operation(tenant_shard_id)
2037 0 : .await
2038 0 : .map_err(TenantStateError::Other);
2039 0 : }
2040 :
2041 : // Flush pending deletions, so that they have a good chance of passing validation
2042 : // before this tenant is potentially re-attached elsewhere.
2043 0 : deletion_queue_client.flush_advisory();
2044 :
2045 0 : removal_result
2046 0 : }
2047 :
2048 0 : pub(crate) fn list_tenants(
2049 0 : &self,
2050 0 : ) -> Result<Vec<(TenantShardId, TenantState, Generation)>, TenantMapListError> {
2051 0 : let tenants = self.tenants.read().unwrap();
2052 0 : let m = match &*tenants {
2053 0 : TenantsMap::Initializing => return Err(TenantMapListError::Initializing),
2054 0 : TenantsMap::Open(m) | TenantsMap::ShuttingDown(m) => m,
2055 : };
2056 0 : Ok(m.iter()
2057 0 : .filter_map(|(id, tenant)| match tenant {
2058 0 : TenantSlot::Attached(tenant) => {
2059 0 : Some((*id, tenant.current_state(), tenant.generation()))
2060 : }
2061 0 : TenantSlot::Secondary(_) => None,
2062 0 : TenantSlot::InProgress(_) => None,
2063 0 : })
2064 0 : .collect())
2065 0 : }
2066 :
2067 : /// Completes an earlier prepared timeline detach ancestor.
2068 0 : pub(crate) async fn complete_detaching_timeline_ancestor(
2069 0 : &self,
2070 0 : tenant_shard_id: TenantShardId,
2071 0 : timeline_id: TimelineId,
2072 0 : prepared: PreparedTimelineDetach,
2073 0 : behavior: DetachBehavior,
2074 0 : mut attempt: detach_ancestor::Attempt,
2075 0 : ctx: &RequestContext,
2076 0 : ) -> Result<HashSet<TimelineId>, detach_ancestor::Error> {
2077 : use detach_ancestor::Error;
2078 :
2079 0 : let slot_guard = self
2080 0 : .tenant_map_acquire_slot(&tenant_shard_id, TenantSlotAcquireMode::MustExist)
2081 0 : .map_err(|e| {
2082 : use TenantSlotError::*;
2083 :
2084 0 : match e {
2085 0 : MapState(TenantMapError::ShuttingDown) => Error::ShuttingDown,
2086 0 : NotFound(_) | InProgress | MapState(_) => Error::DetachReparent(e.into()),
2087 : }
2088 0 : })?;
2089 :
2090 0 : let tenant = {
2091 0 : let old_slot = slot_guard
2092 0 : .get_old_value()
2093 0 : .as_ref()
2094 0 : .expect("requested MustExist");
2095 :
2096 0 : let Some(tenant) = old_slot.get_attached() else {
2097 0 : return Err(Error::DetachReparent(anyhow::anyhow!(
2098 0 : "Tenant is not in attached state"
2099 0 : )));
2100 : };
2101 :
2102 0 : if !tenant.is_active() {
2103 0 : return Err(Error::DetachReparent(anyhow::anyhow!(
2104 0 : "Tenant is not active"
2105 0 : )));
2106 0 : }
2107 :
2108 0 : tenant.clone()
2109 : };
2110 :
2111 0 : let timeline = tenant
2112 0 : .get_timeline(timeline_id, true)
2113 0 : .map_err(Error::NotFound)?;
2114 :
2115 0 : let resp = timeline
2116 0 : .detach_from_ancestor_and_reparent(
2117 0 : &tenant,
2118 0 : prepared,
2119 0 : attempt.ancestor_timeline_id,
2120 0 : attempt.ancestor_lsn,
2121 0 : behavior,
2122 0 : ctx,
2123 0 : )
2124 0 : .await?;
2125 :
2126 0 : let mut slot_guard = slot_guard;
2127 :
2128 0 : let tenant = if resp.reset_tenant_required() {
2129 0 : attempt.before_reset_tenant();
2130 :
2131 0 : let (_guard, progress) = utils::completion::channel();
2132 0 : match tenant.shutdown(progress, ShutdownMode::Reload).await {
2133 0 : Ok(()) => {
2134 0 : slot_guard.drop_old_value().expect("it was just shutdown");
2135 0 : }
2136 0 : Err(_barrier) => {
2137 0 : slot_guard.revert();
2138 : // this really should not happen, at all, unless a shutdown without acquiring
2139 : // tenant slot was already going? regardless, on restart the attempt tracking
2140 : // will reset to retryable.
2141 0 : return Err(Error::ShuttingDown);
2142 : }
2143 : }
2144 :
2145 0 : let tenant_path = self.conf.tenant_path(&tenant_shard_id);
2146 0 : let config = TenantShard::load_tenant_config(self.conf, &tenant_shard_id)
2147 0 : .map_err(|e| Error::DetachReparent(e.into()))?;
2148 :
2149 0 : let shard_identity = config.shard;
2150 0 : let tenant = tenant_spawn(
2151 0 : self.conf,
2152 0 : tenant_shard_id,
2153 0 : &tenant_path,
2154 0 : self.resources.clone(),
2155 0 : AttachedTenantConf::try_from(self.conf, config).map_err(Error::DetachReparent)?,
2156 0 : shard_identity,
2157 0 : None,
2158 0 : SpawnMode::Eager,
2159 0 : ctx,
2160 : )
2161 0 : .map_err(|_| Error::ShuttingDown)?;
2162 :
2163 : {
2164 0 : let mut g = tenant.ongoing_timeline_detach.lock().unwrap();
2165 0 : assert!(
2166 0 : g.is_none(),
2167 0 : "there cannot be any new timeline detach ancestor on newly created tenant"
2168 : );
2169 0 : *g = Some((attempt.timeline_id, attempt.new_barrier()));
2170 : }
2171 :
2172 : // if we bail out here, we will not allow a new attempt, which should be fine.
2173 : // pageserver should be shutting down regardless? tenant_reset would help, unless it
2174 : // runs into the same problem.
2175 0 : slot_guard
2176 0 : .upsert(TenantSlot::Attached(tenant.clone()))
2177 0 : .map_err(|e| match e {
2178 0 : TenantSlotUpsertError::ShuttingDown(_) => Error::ShuttingDown,
2179 0 : other => Error::DetachReparent(other.into()),
2180 0 : })?;
2181 0 : tenant
2182 : } else {
2183 0 : tracing::info!("skipping tenant_reset as no changes made required it");
2184 0 : tenant
2185 : };
2186 :
2187 0 : if let Some(reparented) = resp.completed() {
2188 : // finally ask the restarted tenant to complete the detach
2189 : //
2190 : // rationale for 9999s: we don't really have a timetable here; if retried, the caller
2191 : // will get an 503.
2192 0 : tenant
2193 0 : .wait_to_become_active(std::time::Duration::from_secs(9999))
2194 0 : .await
2195 0 : .map_err(|e| {
2196 : use GetActiveTenantError::{Cancelled, WillNotBecomeActive};
2197 : use pageserver_api::models::TenantState;
2198 0 : match e {
2199 : Cancelled | WillNotBecomeActive(TenantState::Stopping { .. }) => {
2200 0 : Error::ShuttingDown
2201 : }
2202 0 : other => Error::Complete(other.into()),
2203 : }
2204 0 : })?;
2205 :
2206 0 : utils::pausable_failpoint!(
2207 : "timeline-detach-ancestor::after_activating_before_finding-pausable"
2208 : );
2209 :
2210 0 : let timeline = tenant
2211 0 : .get_timeline(attempt.timeline_id, true)
2212 0 : .map_err(Error::NotFound)?;
2213 :
2214 0 : timeline
2215 0 : .complete_detaching_timeline_ancestor(&tenant, attempt, ctx)
2216 0 : .await
2217 0 : .map(|()| reparented)
2218 : } else {
2219 : // at least the latest versions have now been downloaded and refreshed; be ready to
2220 : // retry another time.
2221 0 : Err(Error::FailedToReparentAll)
2222 : }
2223 0 : }
2224 :
2225 : /// A page service client sends a TenantId, and to look up the correct Tenant we must
2226 : /// resolve this to a fully qualified TenantShardId.
2227 : ///
2228 : /// During shard splits: we shall see parent shards in InProgress state and skip them, and
2229 : /// instead match on child shards which should appear in Attached state. Very early in a shard
2230 : /// split, or in other cases where a shard is InProgress, we will return our own InProgress result
2231 : /// to instruct the caller to wait for that to finish before querying again.
2232 0 : pub(crate) fn resolve_attached_shard(
2233 0 : &self,
2234 0 : tenant_id: &TenantId,
2235 0 : selector: ShardSelector,
2236 0 : ) -> ShardResolveResult {
2237 0 : let tenants = self.tenants.read().unwrap();
2238 0 : let mut want_shard: Option<ShardIndex> = None;
2239 0 : let mut any_in_progress = None;
2240 :
2241 0 : match &*tenants {
2242 0 : TenantsMap::Initializing => ShardResolveResult::NotFound,
2243 0 : TenantsMap::Open(m) | TenantsMap::ShuttingDown(m) => {
2244 0 : for slot in m.range(TenantShardId::tenant_range(*tenant_id)) {
2245 : // Ignore all slots that don't contain an attached tenant
2246 0 : let tenant = match &slot.1 {
2247 0 : TenantSlot::Attached(t) => t,
2248 0 : TenantSlot::InProgress(barrier) => {
2249 : // We might still find a usable shard, but in case we don't, remember that
2250 : // we saw at least one InProgress slot, so that we can distinguish this case
2251 : // from a simple NotFound in our return value.
2252 0 : any_in_progress = Some(barrier.clone());
2253 0 : continue;
2254 : }
2255 0 : _ => continue,
2256 : };
2257 :
2258 0 : match selector {
2259 0 : ShardSelector::Zero if slot.0.shard_number == ShardNumber(0) => {
2260 0 : return ShardResolveResult::Found(tenant.clone());
2261 : }
2262 0 : ShardSelector::Page(key) => {
2263 : // Each time we find an attached slot with a different shard count,
2264 : // recompute the expected shard number: during shard splits we might
2265 : // have multiple shards with the old shard count.
2266 0 : if want_shard.is_none()
2267 0 : || want_shard.unwrap().shard_count != tenant.shard_identity.count
2268 0 : {
2269 0 : want_shard = Some(ShardIndex {
2270 0 : shard_number: tenant.shard_identity.get_shard_number(&key),
2271 0 : shard_count: tenant.shard_identity.count,
2272 0 : });
2273 0 : }
2274 :
2275 0 : if Some(ShardIndex {
2276 0 : shard_number: tenant.shard_identity.number,
2277 0 : shard_count: tenant.shard_identity.count,
2278 0 : }) == want_shard
2279 : {
2280 0 : return ShardResolveResult::Found(tenant.clone());
2281 0 : }
2282 : }
2283 0 : ShardSelector::Known(shard)
2284 0 : if tenant.shard_identity.shard_index() == shard =>
2285 : {
2286 0 : return ShardResolveResult::Found(tenant.clone());
2287 : }
2288 0 : _ => continue,
2289 : }
2290 : }
2291 :
2292 : // Fall through: we didn't find a slot that was in Attached state & matched our selector. If
2293 : // we found one or more InProgress slot, indicate to caller that they should retry later. Otherwise
2294 : // this requested shard simply isn't found.
2295 0 : if let Some(barrier) = any_in_progress {
2296 0 : ShardResolveResult::InProgress(barrier)
2297 : } else {
2298 0 : ShardResolveResult::NotFound
2299 : }
2300 : }
2301 : }
2302 0 : }
2303 :
2304 : /// Calculate the tenant shards' contributions to this pageserver's utilization metrics. The
2305 : /// returned values are:
2306 : /// - the number of bytes of local disk space this pageserver's shards are requesting, i.e.
2307 : /// how much space they would use if not impacted by disk usage eviction.
2308 : /// - the number of tenant shards currently on this pageserver, including attached
2309 : /// and secondary.
2310 : ///
2311 : /// This function is quite expensive: callers are expected to cache the result and
2312 : /// limit how often they call it.
2313 0 : pub(crate) fn calculate_utilization(&self) -> Result<(u64, u32), TenantMapListError> {
2314 0 : let tenants = self.tenants.read().unwrap();
2315 0 : let m = match &*tenants {
2316 0 : TenantsMap::Initializing => return Err(TenantMapListError::Initializing),
2317 0 : TenantsMap::Open(m) | TenantsMap::ShuttingDown(m) => m,
2318 : };
2319 0 : let shard_count = m.len();
2320 0 : let mut wanted_bytes = 0;
2321 :
2322 0 : for tenant_slot in m.values() {
2323 0 : match tenant_slot {
2324 0 : TenantSlot::InProgress(_barrier) => {
2325 : // While a slot is being changed, we can't know how much storage it wants. This
2326 : // means this function's output can fluctuate if a lot of changes are going on
2327 : // (such as transitions from secondary to attached).
2328 : //
2329 : // We could wait for the barrier and retry, but it's important that the utilization
2330 : // API is responsive, and the data quality impact is not very significant.
2331 0 : continue;
2332 : }
2333 0 : TenantSlot::Attached(tenant) => {
2334 0 : wanted_bytes += tenant.local_storage_wanted();
2335 0 : }
2336 0 : TenantSlot::Secondary(secondary) => {
2337 0 : let progress = secondary.progress.lock().unwrap();
2338 0 : wanted_bytes += if progress.heatmap_mtime.is_some() {
2339 : // If we have heatmap info, then we will 'want' the sum
2340 : // of the size of layers in the heatmap: this is how much space
2341 : // we would use if not doing any eviction.
2342 0 : progress.bytes_total
2343 : } else {
2344 : // In the absence of heatmap info, assume that the secondary location simply
2345 : // needs as much space as it is currently using.
2346 0 : secondary.resident_size_metric.get()
2347 : }
2348 : }
2349 : }
2350 : }
2351 :
2352 0 : Ok((wanted_bytes, shard_count as u32))
2353 0 : }
2354 :
2355 : #[instrument(skip_all, fields(tenant_id=%tenant_shard_id.tenant_id, shard_id=%tenant_shard_id.shard_slug(), %timeline_id))]
2356 : pub(crate) async fn immediate_gc(
2357 : &self,
2358 : tenant_shard_id: TenantShardId,
2359 : timeline_id: TimelineId,
2360 : gc_req: TimelineGcRequest,
2361 : cancel: CancellationToken,
2362 : ctx: &RequestContext,
2363 : ) -> Result<GcResult, ApiError> {
2364 : let tenant = {
2365 : let guard = self.tenants.read().unwrap();
2366 : guard
2367 : .get(&tenant_shard_id)
2368 : .cloned()
2369 0 : .with_context(|| format!("tenant {tenant_shard_id}"))
2370 0 : .map_err(|e| ApiError::NotFound(e.into()))?
2371 : };
2372 :
2373 0 : let gc_horizon = gc_req.gc_horizon.unwrap_or_else(|| tenant.get_gc_horizon());
2374 : // Use tenant's pitr setting
2375 : let pitr = tenant.get_pitr_interval();
2376 :
2377 : tenant.wait_to_become_active(ACTIVE_TENANT_TIMEOUT).await?;
2378 :
2379 : // Run in task_mgr to avoid race with tenant_detach operation
2380 : let ctx: RequestContext =
2381 : ctx.detached_child(TaskKind::GarbageCollector, DownloadBehavior::Download);
2382 :
2383 : let _gate_guard = tenant.gate.enter().map_err(|_| ApiError::ShuttingDown)?;
2384 :
2385 : fail::fail_point!("immediate_gc_task_pre");
2386 :
2387 : #[allow(unused_mut)]
2388 : let mut result = tenant
2389 : .gc_iteration(Some(timeline_id), gc_horizon, pitr, &cancel, &ctx)
2390 : .await;
2391 : // FIXME: `gc_iteration` can return an error for multiple reasons; we should handle it
2392 : // better once the types support it.
2393 :
2394 : #[cfg(feature = "testing")]
2395 : {
2396 : // we need to synchronize with drop completion for python tests without polling for
2397 : // log messages
2398 : if let Ok(result) = result.as_mut() {
2399 : let mut js = tokio::task::JoinSet::new();
2400 : for layer in std::mem::take(&mut result.doomed_layers) {
2401 : js.spawn(layer.wait_drop());
2402 : }
2403 : tracing::info!(
2404 : total = js.len(),
2405 : "starting to wait for the gc'd layers to be dropped"
2406 : );
2407 : while let Some(res) = js.join_next().await {
2408 : res.expect("wait_drop should not panic");
2409 : }
2410 : }
2411 :
2412 : let timeline = tenant.get_timeline(timeline_id, false).ok();
2413 0 : let rtc = timeline.as_ref().map(|x| &x.remote_client);
2414 :
2415 : if let Some(rtc) = rtc {
2416 : // layer drops schedule actions on remote timeline client to actually do the
2417 : // deletions; don't care about the shutdown error, just exit fast
2418 : drop(rtc.wait_completion().await);
2419 : }
2420 : }
2421 :
2422 0 : result.map_err(|e| match e {
2423 0 : GcError::TenantCancelled | GcError::TimelineCancelled => ApiError::ShuttingDown,
2424 : GcError::TimelineNotFound => {
2425 0 : ApiError::NotFound(anyhow::anyhow!("Timeline not found").into())
2426 : }
2427 0 : other => ApiError::InternalServerError(anyhow::anyhow!(other)),
2428 0 : })
2429 : }
2430 :
2431 : /// Stops and removes the tenant from memory, if it's not [`TenantState::Stopping`] already, bails otherwise.
2432 : /// Allows to remove other tenant resources manually, via `tenant_cleanup`.
2433 : /// If the cleanup fails, tenant will stay in memory in [`TenantState::Broken`] state, and another removal
2434 1 : async fn remove_tenant_from_memory<V, F>(
2435 1 : &self,
2436 1 : tenant_shard_id: TenantShardId,
2437 1 : tenant_cleanup: F,
2438 1 : ) -> Result<V, TenantStateError>
2439 1 : where
2440 1 : F: std::future::Future<Output = anyhow::Result<V>>,
2441 1 : {
2442 1 : let mut slot_guard =
2443 1 : self.tenant_map_acquire_slot(&tenant_shard_id, TenantSlotAcquireMode::MustExist)?;
2444 :
2445 : // allow pageserver shutdown to await for our completion
2446 1 : let (_guard, progress) = completion::channel();
2447 :
2448 : // The SlotGuard allows us to manipulate the Tenant object without fear of some
2449 : // concurrent API request doing something else for the same tenant ID.
2450 1 : let attached_tenant = match slot_guard.get_old_value() {
2451 1 : Some(TenantSlot::Attached(tenant)) => {
2452 : // whenever we remove a tenant from memory, we don't want to flush and wait for upload
2453 1 : let shutdown_mode = ShutdownMode::Hard;
2454 :
2455 : // shutdown is sure to transition tenant to stopping, and wait for all tasks to complete, so
2456 : // that we can continue safely to cleanup.
2457 1 : match tenant.shutdown(progress, shutdown_mode).await {
2458 1 : Ok(()) => {}
2459 0 : Err(_other) => {
2460 : // if pageserver shutdown or other detach/ignore is already ongoing, we don't want to
2461 : // wait for it but return an error right away because these are distinct requests.
2462 0 : slot_guard.revert();
2463 0 : return Err(TenantStateError::IsStopping(tenant_shard_id));
2464 : }
2465 : }
2466 1 : Some(tenant)
2467 : }
2468 0 : Some(TenantSlot::Secondary(secondary_state)) => {
2469 0 : tracing::info!("Shutting down in secondary mode");
2470 0 : secondary_state.shutdown().await;
2471 0 : None
2472 : }
2473 : Some(TenantSlot::InProgress(_)) => {
2474 : // Acquiring a slot guarantees its old value was not InProgress
2475 0 : unreachable!();
2476 : }
2477 0 : None => None,
2478 : };
2479 :
2480 1 : match tenant_cleanup
2481 1 : .await
2482 1 : .with_context(|| format!("Failed to run cleanup for tenant {tenant_shard_id}"))
2483 : {
2484 1 : Ok(hook_value) => {
2485 : // Success: drop the old TenantSlot::Attached.
2486 1 : slot_guard
2487 1 : .drop_old_value()
2488 1 : .expect("We just called shutdown");
2489 :
2490 1 : Ok(hook_value)
2491 : }
2492 0 : Err(e) => {
2493 : // If we had a Tenant, set it to Broken and put it back in the TenantsMap
2494 0 : if let Some(attached_tenant) = attached_tenant {
2495 0 : attached_tenant.set_broken(e.to_string()).await;
2496 0 : }
2497 : // Leave the broken tenant in the map
2498 0 : slot_guard.revert();
2499 :
2500 0 : Err(TenantStateError::Other(e))
2501 : }
2502 : }
2503 1 : }
2504 : }
2505 :
2506 : #[derive(Debug, thiserror::Error)]
2507 : pub(crate) enum GetTenantError {
2508 : /// NotFound is a TenantId rather than TenantShardId, because this error type is used from
2509 : /// getters that use a TenantId and a ShardSelector, not just getters that target a specific shard.
2510 : #[error("Tenant {0} not found")]
2511 : NotFound(TenantId),
2512 :
2513 : #[error("Tenant {0} not found")]
2514 : ShardNotFound(TenantShardId),
2515 :
2516 : #[error("Tenant {0} is not active")]
2517 : NotActive(TenantShardId),
2518 :
2519 : // Initializing or shutting down: cannot authoritatively say whether we have this tenant
2520 : #[error("Tenant map is not available: {0}")]
2521 : MapState(#[from] TenantMapError),
2522 : }
2523 :
2524 : #[derive(thiserror::Error, Debug)]
2525 : pub(crate) enum GetActiveTenantError {
2526 : /// We may time out either while TenantSlot is InProgress, or while the Tenant
2527 : /// is in a non-Active state
2528 : #[error(
2529 : "Timed out waiting {wait_time:?} for tenant active state. Latest state: {latest_state:?}"
2530 : )]
2531 : WaitForActiveTimeout {
2532 : latest_state: Option<TenantState>,
2533 : wait_time: Duration,
2534 : },
2535 :
2536 : /// The TenantSlot is absent, or in secondary mode
2537 : #[error(transparent)]
2538 : NotFound(#[from] GetTenantError),
2539 :
2540 : /// Cancellation token fired while we were waiting
2541 : #[error("cancelled")]
2542 : Cancelled,
2543 :
2544 : /// Tenant exists, but is in a state that cannot become active (e.g. Stopping, Broken)
2545 : #[error("will not become active. Current state: {0}")]
2546 : WillNotBecomeActive(TenantState),
2547 :
2548 : /// Broken is logically a subset of WillNotBecomeActive, but a distinct error is useful as
2549 : /// WillNotBecomeActive is a permitted error under some circumstances, whereas broken should
2550 : /// never happen.
2551 : #[error("Tenant is broken: {0}")]
2552 : Broken(String),
2553 :
2554 : #[error("reconnect to switch tenant id")]
2555 : SwitchedTenant,
2556 : }
2557 :
2558 : #[derive(Debug, thiserror::Error)]
2559 : pub(crate) enum DeleteTimelineError {
2560 : #[error("Tenant {0}")]
2561 : Tenant(#[from] GetTenantError),
2562 :
2563 : #[error("Timeline {0}")]
2564 : Timeline(#[from] crate::tenant::DeleteTimelineError),
2565 : }
2566 :
2567 : #[derive(Debug, thiserror::Error)]
2568 : pub(crate) enum TenantStateError {
2569 : #[error("Tenant {0} is stopping")]
2570 : IsStopping(TenantShardId),
2571 : #[error(transparent)]
2572 : SlotError(#[from] TenantSlotError),
2573 : #[error(transparent)]
2574 : SlotUpsertError(#[from] TenantSlotUpsertError),
2575 : #[error(transparent)]
2576 : Other(#[from] anyhow::Error),
2577 : }
2578 :
2579 : #[derive(Debug, thiserror::Error)]
2580 : pub(crate) enum TenantMapListError {
2581 : #[error("tenant map is still initiailizing")]
2582 : Initializing,
2583 : }
2584 :
2585 : #[derive(Debug, thiserror::Error)]
2586 : pub(crate) enum TenantMapInsertError {
2587 : #[error(transparent)]
2588 : SlotError(#[from] TenantSlotError),
2589 : #[error(transparent)]
2590 : SlotUpsertError(#[from] TenantSlotUpsertError),
2591 : #[error(transparent)]
2592 : Other(#[from] anyhow::Error),
2593 : }
2594 :
2595 : /// Superset of TenantMapError: issues that can occur when acquiring a slot
2596 : /// for a particular tenant ID.
2597 : #[derive(Debug, thiserror::Error)]
2598 : pub(crate) enum TenantSlotError {
2599 : /// When acquiring a slot with the expectation that the tenant already exists.
2600 : #[error("Tenant {0} not found")]
2601 : NotFound(TenantShardId),
2602 :
2603 : // Tried to read a slot that is currently being mutated by another administrative
2604 : // operation.
2605 : #[error("tenant has a state change in progress, try again later")]
2606 : InProgress,
2607 :
2608 : #[error(transparent)]
2609 : MapState(#[from] TenantMapError),
2610 : }
2611 :
2612 : /// Superset of TenantMapError: issues that can occur when using a SlotGuard
2613 : /// to insert a new value.
2614 : #[derive(thiserror::Error)]
2615 : pub(crate) enum TenantSlotUpsertError {
2616 : /// An error where the slot is in an unexpected state, indicating a code bug
2617 : #[error("Internal error updating Tenant")]
2618 : InternalError(Cow<'static, str>),
2619 :
2620 : #[error(transparent)]
2621 : MapState(TenantMapError),
2622 :
2623 : // If we encounter TenantManager shutdown during upsert, we must carry the Completion
2624 : // from the SlotGuard, so that the caller can hold it while they clean up: otherwise
2625 : // TenantManager shutdown might race ahead before we're done cleaning up any Tenant that
2626 : // was protected by the SlotGuard.
2627 : #[error("Shutting down")]
2628 : ShuttingDown((TenantSlot, utils::completion::Completion)),
2629 : }
2630 :
2631 : impl std::fmt::Debug for TenantSlotUpsertError {
2632 0 : fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
2633 0 : match self {
2634 0 : Self::InternalError(reason) => write!(f, "Internal Error {reason}"),
2635 0 : Self::MapState(map_error) => write!(f, "Tenant map state: {map_error:?}"),
2636 0 : Self::ShuttingDown(_completion) => write!(f, "Tenant map shutting down"),
2637 : }
2638 0 : }
2639 : }
2640 :
2641 : #[derive(Debug, thiserror::Error)]
2642 : enum TenantSlotDropError {
2643 : /// It is only legal to drop a TenantSlot if its contents are fully shut down
2644 : #[error("Tenant was not shut down")]
2645 : NotShutdown,
2646 : }
2647 :
2648 : /// Errors that can happen any time we are walking the tenant map to try and acquire
2649 : /// the TenantSlot for a particular tenant.
2650 : #[derive(Debug, thiserror::Error)]
2651 : pub(crate) enum TenantMapError {
2652 : // Tried to read while initializing
2653 : #[error("tenant map is still initializing")]
2654 : StillInitializing,
2655 :
2656 : // Tried to read while shutting down
2657 : #[error("tenant map is shutting down")]
2658 : ShuttingDown,
2659 : }
2660 :
2661 : /// Guards a particular tenant_id's content in the TenantsMap.
2662 : ///
2663 : /// While this structure exists, the TenantsMap will contain a [`TenantSlot::InProgress`]
2664 : /// for this tenant, which acts as a marker for any operations targeting
2665 : /// this tenant to retry later, or wait for the InProgress state to end.
2666 : ///
2667 : /// This structure enforces the important invariant that we do not have overlapping
2668 : /// tasks that will try to use local storage for a the same tenant ID: we enforce that
2669 : /// the previous contents of a slot have been shut down before the slot can be
2670 : /// left empty or used for something else
2671 : ///
2672 : /// Holders of a SlotGuard should explicitly dispose of it, using either `upsert`
2673 : /// to provide a new value, or `revert` to put the slot back into its initial
2674 : /// state. If the SlotGuard is dropped without calling either of these, then
2675 : /// we will leave the slot empty if our `old_value` is already shut down, else
2676 : /// we will replace the slot with `old_value` (equivalent to doing a revert).
2677 : ///
2678 : /// The `old_value` may be dropped before the SlotGuard is dropped, by calling
2679 : /// `drop_old_value`. It is an error to call this without shutting down
2680 : /// the conents of `old_value`.
2681 : pub(crate) struct SlotGuard<'a> {
2682 : tenant_shard_id: TenantShardId,
2683 : old_value: Option<TenantSlot>,
2684 : upserted: bool,
2685 :
2686 : /// [`TenantSlot::InProgress`] carries the corresponding Barrier: it will
2687 : /// release any waiters as soon as this SlotGuard is dropped.
2688 : completion: utils::completion::Completion,
2689 :
2690 : tenants: &'a std::sync::RwLock<TenantsMap>,
2691 : }
2692 :
2693 : impl<'a> SlotGuard<'a> {
2694 1 : fn new(
2695 1 : tenant_shard_id: TenantShardId,
2696 1 : old_value: Option<TenantSlot>,
2697 1 : completion: utils::completion::Completion,
2698 1 : tenants: &'a std::sync::RwLock<TenantsMap>,
2699 1 : ) -> Self {
2700 1 : Self {
2701 1 : tenant_shard_id,
2702 1 : old_value,
2703 1 : upserted: false,
2704 1 : completion,
2705 1 : tenants,
2706 1 : }
2707 1 : }
2708 :
2709 : /// Get any value that was present in the slot before we acquired ownership
2710 : /// of it: in state transitions, this will be the old state.
2711 : ///
2712 : // FIXME: get_ prefix
2713 : // FIXME: this should be .as_ref() -- unsure why no clippy
2714 1 : fn get_old_value(&self) -> &Option<TenantSlot> {
2715 1 : &self.old_value
2716 1 : }
2717 :
2718 : /// Emplace a new value in the slot. This consumes the guard, and after
2719 : /// returning, the slot is no longer protected from concurrent changes.
2720 0 : fn upsert(mut self, new_value: TenantSlot) -> Result<(), TenantSlotUpsertError> {
2721 0 : if !self.old_value_is_shutdown() {
2722 : // This is a bug: callers should never try to drop an old value without
2723 : // shutting it down
2724 0 : return Err(TenantSlotUpsertError::InternalError(
2725 0 : "Old TenantSlot value not shut down".into(),
2726 0 : ));
2727 0 : }
2728 :
2729 0 : let replaced: Option<TenantSlot> = {
2730 0 : let mut locked = self.tenants.write().unwrap();
2731 :
2732 0 : if let TenantSlot::InProgress(_) = new_value {
2733 : // It is never expected to try and upsert InProgress via this path: it should
2734 : // only be written via the tenant_map_acquire_slot path. If we hit this it's a bug.
2735 0 : return Err(TenantSlotUpsertError::InternalError(
2736 0 : "Attempt to upsert an InProgress state".into(),
2737 0 : ));
2738 0 : }
2739 :
2740 0 : let m = match &mut *locked {
2741 : TenantsMap::Initializing => {
2742 0 : return Err(TenantSlotUpsertError::MapState(
2743 0 : TenantMapError::StillInitializing,
2744 0 : ));
2745 : }
2746 : TenantsMap::ShuttingDown(_) => {
2747 0 : return Err(TenantSlotUpsertError::ShuttingDown((
2748 0 : new_value,
2749 0 : self.completion.clone(),
2750 0 : )));
2751 : }
2752 0 : TenantsMap::Open(m) => m,
2753 : };
2754 :
2755 0 : METRICS.slot_inserted(&new_value);
2756 :
2757 0 : let replaced = m.insert(self.tenant_shard_id, new_value);
2758 0 : self.upserted = true;
2759 0 : if let Some(replaced) = replaced.as_ref() {
2760 0 : METRICS.slot_removed(replaced);
2761 0 : }
2762 :
2763 0 : replaced
2764 : };
2765 :
2766 : // Sanity check: on an upsert we should always be replacing an InProgress marker
2767 0 : match replaced {
2768 : Some(TenantSlot::InProgress(_)) => {
2769 : // Expected case: we find our InProgress in the map: nothing should have
2770 : // replaced it because the code that acquires slots will not grant another
2771 : // one for the same TenantId.
2772 0 : Ok(())
2773 : }
2774 : None => {
2775 0 : METRICS.unexpected_errors.inc();
2776 0 : error!(
2777 : tenant_shard_id = %self.tenant_shard_id,
2778 0 : "Missing InProgress marker during tenant upsert, this is a bug."
2779 : );
2780 0 : Err(TenantSlotUpsertError::InternalError(
2781 0 : "Missing InProgress marker during tenant upsert".into(),
2782 0 : ))
2783 : }
2784 0 : Some(slot) => {
2785 0 : METRICS.unexpected_errors.inc();
2786 0 : error!(tenant_shard_id=%self.tenant_shard_id, "Unexpected contents of TenantSlot during upsert, this is a bug. Contents: {:?}", slot);
2787 0 : Err(TenantSlotUpsertError::InternalError(
2788 0 : "Unexpected contents of TenantSlot".into(),
2789 0 : ))
2790 : }
2791 : }
2792 0 : }
2793 :
2794 : /// Replace the InProgress slot with whatever was in the guard when we started
2795 0 : fn revert(mut self) {
2796 0 : if let Some(value) = self.old_value.take() {
2797 0 : match self.upsert(value) {
2798 0 : Err(TenantSlotUpsertError::InternalError(_)) => {
2799 0 : // We already logged the error, nothing else we can do.
2800 0 : }
2801 : Err(
2802 : TenantSlotUpsertError::MapState(_) | TenantSlotUpsertError::ShuttingDown(_),
2803 0 : ) => {
2804 0 : // If the map is shutting down, we need not replace anything
2805 0 : }
2806 0 : Ok(()) => {}
2807 : }
2808 0 : }
2809 0 : }
2810 :
2811 : /// We may never drop our old value until it is cleanly shut down: otherwise we might leave
2812 : /// rogue background tasks that would write to the local tenant directory that this guard
2813 : /// is responsible for protecting
2814 1 : fn old_value_is_shutdown(&self) -> bool {
2815 1 : match self.old_value.as_ref() {
2816 1 : Some(TenantSlot::Attached(tenant)) => tenant.gate.close_complete(),
2817 0 : Some(TenantSlot::Secondary(secondary_tenant)) => secondary_tenant.gate.close_complete(),
2818 : Some(TenantSlot::InProgress(_)) => {
2819 : // A SlotGuard cannot be constructed for a slot that was already InProgress
2820 0 : unreachable!()
2821 : }
2822 0 : None => true,
2823 : }
2824 1 : }
2825 :
2826 : /// The guard holder is done with the old value of the slot: they are obliged to already
2827 : /// shut it down before we reach this point.
2828 1 : fn drop_old_value(&mut self) -> Result<(), TenantSlotDropError> {
2829 1 : if !self.old_value_is_shutdown() {
2830 0 : Err(TenantSlotDropError::NotShutdown)
2831 : } else {
2832 1 : self.old_value.take();
2833 1 : Ok(())
2834 : }
2835 1 : }
2836 : }
2837 :
2838 : impl<'a> Drop for SlotGuard<'a> {
2839 1 : fn drop(&mut self) {
2840 1 : if self.upserted {
2841 0 : return;
2842 1 : }
2843 : // Our old value is already shutdown, or it never existed: it is safe
2844 : // for us to fully release the TenantSlot back into an empty state
2845 :
2846 1 : let mut locked = self.tenants.write().unwrap();
2847 :
2848 1 : let m = match &mut *locked {
2849 : TenantsMap::Initializing => {
2850 : // There is no map, this should never happen.
2851 0 : return;
2852 : }
2853 : TenantsMap::ShuttingDown(_) => {
2854 : // When we transition to shutdown, InProgress elements are removed
2855 : // from the map, so we do not need to clean up our Inprogress marker.
2856 : // See [`shutdown_all_tenants0`]
2857 1 : return;
2858 : }
2859 0 : TenantsMap::Open(m) => m,
2860 : };
2861 :
2862 : use std::collections::btree_map::Entry;
2863 0 : match m.entry(self.tenant_shard_id) {
2864 0 : Entry::Occupied(mut entry) => {
2865 0 : if !matches!(entry.get(), TenantSlot::InProgress(_)) {
2866 0 : METRICS.unexpected_errors.inc();
2867 0 : error!(tenant_shard_id=%self.tenant_shard_id, "Unexpected contents of TenantSlot during drop, this is a bug. Contents: {:?}", entry.get());
2868 0 : }
2869 :
2870 0 : if self.old_value_is_shutdown() {
2871 0 : METRICS.slot_removed(entry.get());
2872 0 : entry.remove();
2873 0 : } else {
2874 0 : let inserting = self.old_value.take().unwrap();
2875 0 : METRICS.slot_inserted(&inserting);
2876 0 : let replaced = entry.insert(inserting);
2877 0 : METRICS.slot_removed(&replaced);
2878 0 : }
2879 : }
2880 : Entry::Vacant(_) => {
2881 0 : METRICS.unexpected_errors.inc();
2882 0 : error!(
2883 : tenant_shard_id = %self.tenant_shard_id,
2884 0 : "Missing InProgress marker during SlotGuard drop, this is a bug."
2885 : );
2886 : }
2887 : }
2888 1 : }
2889 : }
2890 :
2891 : enum TenantSlotPeekMode {
2892 : /// In Read mode, peek will be permitted to see the slots even if the pageserver is shutting down
2893 : Read,
2894 : /// In Write mode, trying to peek at a slot while the pageserver is shutting down is an error
2895 : Write,
2896 : }
2897 :
2898 0 : fn tenant_map_peek_slot<'a>(
2899 0 : tenants: &'a std::sync::RwLockReadGuard<'a, TenantsMap>,
2900 0 : tenant_shard_id: &TenantShardId,
2901 0 : mode: TenantSlotPeekMode,
2902 0 : ) -> Result<Option<&'a TenantSlot>, TenantMapError> {
2903 0 : match tenants.deref() {
2904 0 : TenantsMap::Initializing => Err(TenantMapError::StillInitializing),
2905 0 : TenantsMap::ShuttingDown(m) => match mode {
2906 : TenantSlotPeekMode::Read => Ok(Some(
2907 : // When reading in ShuttingDown state, we must translate None results
2908 : // into a ShuttingDown error, because absence of a tenant shard ID in the map
2909 : // isn't a reliable indicator of the tenant being gone: it might have been
2910 : // InProgress when shutdown started, and cleaned up from that state such
2911 : // that it's now no longer in the map. Callers will have to wait until
2912 : // we next start up to get a proper answer. This avoids incorrect 404 API responses.
2913 0 : m.get(tenant_shard_id).ok_or(TenantMapError::ShuttingDown)?,
2914 : )),
2915 0 : TenantSlotPeekMode::Write => Err(TenantMapError::ShuttingDown),
2916 : },
2917 0 : TenantsMap::Open(m) => Ok(m.get(tenant_shard_id)),
2918 : }
2919 0 : }
2920 :
2921 : enum TenantSlotAcquireMode {
2922 : /// Acquire the slot irrespective of current state, or whether it already exists
2923 : Any,
2924 : /// Return an error if trying to acquire a slot and it doesn't already exist
2925 : MustExist,
2926 : }
2927 :
2928 : use http_utils::error::ApiError;
2929 : use pageserver_api::models::TimelineGcRequest;
2930 :
2931 : use crate::tenant::gc_result::GcResult;
2932 :
2933 : #[cfg(test)]
2934 : mod tests {
2935 : use std::collections::BTreeMap;
2936 : use std::sync::Arc;
2937 :
2938 : use camino::Utf8PathBuf;
2939 : use storage_broker::BrokerClientChannel;
2940 : use tracing::Instrument;
2941 :
2942 : use super::super::harness::TenantHarness;
2943 : use super::TenantsMap;
2944 : use crate::{
2945 : basebackup_cache::BasebackupCache,
2946 : tenant::{
2947 : TenantSharedResources,
2948 : mgr::{BackgroundPurges, TenantManager, TenantSlot},
2949 : },
2950 : };
2951 :
2952 : #[tokio::test(start_paused = true)]
2953 1 : async fn shutdown_awaits_in_progress_tenant() {
2954 : // Test that if an InProgress tenant is in the map during shutdown, the shutdown will gracefully
2955 : // wait for it to complete before proceeding.
2956 :
2957 1 : let h = TenantHarness::create("shutdown_awaits_in_progress_tenant")
2958 1 : .await
2959 1 : .unwrap();
2960 1 : let (t, _ctx) = h.load().await;
2961 :
2962 : // harness loads it to active, which is forced and nothing is running on the tenant
2963 :
2964 1 : let id = t.tenant_shard_id();
2965 :
2966 : // tenant harness configures the logging and we cannot escape it
2967 1 : let span = h.span();
2968 1 : let _e = span.enter();
2969 :
2970 1 : let tenants = BTreeMap::from([(id, TenantSlot::Attached(t.clone()))]);
2971 :
2972 : // Invoke remove_tenant_from_memory with a cleanup hook that blocks until we manually
2973 : // permit it to proceed: that will stick the tenant in InProgress
2974 :
2975 1 : let (basebackup_cache, _) = BasebackupCache::new(Utf8PathBuf::new(), None);
2976 :
2977 1 : let tenant_manager = TenantManager {
2978 1 : tenants: std::sync::RwLock::new(TenantsMap::Open(tenants)),
2979 1 : conf: h.conf,
2980 : resources: TenantSharedResources {
2981 1 : broker_client: BrokerClientChannel::connect_lazy("foobar.com")
2982 1 : .await
2983 1 : .unwrap(),
2984 1 : remote_storage: h.remote_storage.clone(),
2985 1 : deletion_queue_client: h.deletion_queue.new_client(),
2986 1 : l0_flush_global_state: crate::l0_flush::L0FlushGlobalState::new(
2987 1 : h.conf.l0_flush.clone(),
2988 : ),
2989 1 : basebackup_cache,
2990 1 : feature_resolver: crate::feature_resolver::FeatureResolver::new_disabled(),
2991 : },
2992 1 : cancel: tokio_util::sync::CancellationToken::new(),
2993 1 : background_purges: BackgroundPurges::default(),
2994 : };
2995 :
2996 1 : let tenant_manager = Arc::new(tenant_manager);
2997 :
2998 1 : let (until_cleanup_completed, can_complete_cleanup) = utils::completion::channel();
2999 1 : let (until_cleanup_started, cleanup_started) = utils::completion::channel();
3000 1 : let mut remove_tenant_from_memory_task = {
3001 1 : let tenant_manager = tenant_manager.clone();
3002 1 : let jh = tokio::spawn({
3003 1 : async move {
3004 1 : let cleanup = async move {
3005 1 : drop(until_cleanup_started);
3006 1 : can_complete_cleanup.wait().await;
3007 1 : anyhow::Ok(())
3008 1 : };
3009 1 : tenant_manager.remove_tenant_from_memory(id, cleanup).await
3010 1 : }
3011 1 : .instrument(h.span())
3012 : });
3013 :
3014 : // now the long cleanup should be in place, with the stopping state
3015 1 : cleanup_started.wait().await;
3016 1 : jh
3017 : };
3018 :
3019 1 : let mut shutdown_task = {
3020 1 : let (until_shutdown_started, shutdown_started) = utils::completion::channel();
3021 :
3022 1 : let tenant_manager = tenant_manager.clone();
3023 :
3024 1 : let shutdown_task = tokio::spawn(async move {
3025 1 : drop(until_shutdown_started);
3026 1 : tenant_manager.shutdown_all_tenants0().await;
3027 1 : });
3028 :
3029 1 : shutdown_started.wait().await;
3030 1 : shutdown_task
3031 : };
3032 :
3033 1 : let long_time = std::time::Duration::from_secs(15);
3034 1 : tokio::select! {
3035 1 : _ = &mut shutdown_task => unreachable!("shutdown should block on remove_tenant_from_memory completing"),
3036 1 : _ = &mut remove_tenant_from_memory_task => unreachable!("remove_tenant_from_memory_task should not complete until explicitly unblocked"),
3037 1 : _ = tokio::time::sleep(long_time) => {},
3038 : }
3039 :
3040 1 : drop(until_cleanup_completed);
3041 :
3042 : // Now that we allow it to proceed, shutdown should complete immediately
3043 1 : remove_tenant_from_memory_task.await.unwrap().unwrap();
3044 1 : shutdown_task.await.unwrap();
3045 1 : }
3046 : }
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