Line data Source code
1 : mod downloader;
2 : pub mod heatmap;
3 : mod heatmap_uploader;
4 : mod scheduler;
5 :
6 : use std::{sync::Arc, time::SystemTime};
7 :
8 : use crate::{
9 : context::RequestContext,
10 : disk_usage_eviction_task::DiskUsageEvictionInfo,
11 : metrics::SECONDARY_HEATMAP_TOTAL_SIZE,
12 : task_mgr::{self, TaskKind, BACKGROUND_RUNTIME},
13 : };
14 :
15 : use self::{
16 : downloader::{downloader_task, SecondaryDetail},
17 : heatmap_uploader::heatmap_uploader_task,
18 : };
19 :
20 : use super::{
21 : config::{SecondaryLocationConfig, TenantConfOpt},
22 : mgr::TenantManager,
23 : span::debug_assert_current_span_has_tenant_id,
24 : storage_layer::LayerName,
25 : GetTenantError,
26 : };
27 :
28 : use crate::metrics::SECONDARY_RESIDENT_PHYSICAL_SIZE;
29 : use metrics::UIntGauge;
30 : use pageserver_api::{
31 : models,
32 : shard::{ShardIdentity, TenantShardId},
33 : };
34 : use remote_storage::GenericRemoteStorage;
35 :
36 : use tokio::task::JoinHandle;
37 : use tokio_util::sync::CancellationToken;
38 : use tracing::instrument;
39 : use utils::{completion::Barrier, id::TimelineId, sync::gate::Gate};
40 :
41 : enum DownloadCommand {
42 : Download(TenantShardId),
43 : }
44 : enum UploadCommand {
45 : Upload(TenantShardId),
46 : }
47 :
48 : impl UploadCommand {
49 0 : fn get_tenant_shard_id(&self) -> &TenantShardId {
50 0 : match self {
51 0 : Self::Upload(id) => id,
52 0 : }
53 0 : }
54 : }
55 :
56 : impl DownloadCommand {
57 0 : fn get_tenant_shard_id(&self) -> &TenantShardId {
58 0 : match self {
59 0 : Self::Download(id) => id,
60 0 : }
61 0 : }
62 : }
63 :
64 : struct CommandRequest<T> {
65 : payload: T,
66 : response_tx: tokio::sync::oneshot::Sender<CommandResponse>,
67 : }
68 :
69 : struct CommandResponse {
70 : result: Result<(), SecondaryTenantError>,
71 : }
72 :
73 : #[derive(thiserror::Error, Debug)]
74 : pub(crate) enum SecondaryTenantError {
75 : #[error("{0}")]
76 : GetTenant(GetTenantError),
77 : #[error("shutting down")]
78 : ShuttingDown,
79 : }
80 :
81 : impl From<GetTenantError> for SecondaryTenantError {
82 0 : fn from(gte: GetTenantError) -> Self {
83 0 : Self::GetTenant(gte)
84 0 : }
85 : }
86 :
87 : // Whereas [`Tenant`] represents an attached tenant, this type represents the work
88 : // we do for secondary tenant locations: where we are not serving clients or
89 : // ingesting WAL, but we are maintaining a warm cache of layer files.
90 : //
91 : // This type is all about the _download_ path for secondary mode. The upload path
92 : // runs separately (see [`heatmap_uploader`]) while a regular attached `Tenant` exists.
93 : //
94 : // This structure coordinates TenantManager and SecondaryDownloader,
95 : // so that the downloader can indicate which tenants it is currently
96 : // operating on, and the manager can indicate when a particular
97 : // secondary tenant should cancel any work in flight.
98 : #[derive(Debug)]
99 : pub(crate) struct SecondaryTenant {
100 : /// Carrying a tenant shard ID simplifies callers such as the downloader
101 : /// which need to organize many of these objects by ID.
102 : tenant_shard_id: TenantShardId,
103 :
104 : /// Cancellation token indicates to SecondaryDownloader that it should stop doing
105 : /// any work for this tenant at the next opportunity.
106 : pub(crate) cancel: CancellationToken,
107 :
108 : pub(crate) gate: Gate,
109 :
110 : // Secondary mode does not need the full shard identity or the TenantConfOpt. However,
111 : // storing these enables us to report our full LocationConf, enabling convenient reconciliation
112 : // by the control plane (see [`Self::get_location_conf`])
113 : shard_identity: ShardIdentity,
114 : tenant_conf: std::sync::Mutex<TenantConfOpt>,
115 :
116 : // Internal state used by the Downloader.
117 : detail: std::sync::Mutex<SecondaryDetail>,
118 :
119 : // Public state indicating overall progress of downloads relative to the last heatmap seen
120 : pub(crate) progress: std::sync::Mutex<models::SecondaryProgress>,
121 :
122 : // Sum of layer sizes on local disk
123 : pub(super) resident_size_metric: UIntGauge,
124 :
125 : // Sum of layer sizes in the most recently downloaded heatmap
126 : pub(super) heatmap_total_size_metric: UIntGauge,
127 : }
128 :
129 : impl SecondaryTenant {
130 0 : pub(crate) fn new(
131 0 : tenant_shard_id: TenantShardId,
132 0 : shard_identity: ShardIdentity,
133 0 : tenant_conf: TenantConfOpt,
134 0 : config: &SecondaryLocationConfig,
135 0 : ) -> Arc<Self> {
136 0 : let tenant_id = tenant_shard_id.tenant_id.to_string();
137 0 : let shard_id = format!("{}", tenant_shard_id.shard_slug());
138 0 : let resident_size_metric = SECONDARY_RESIDENT_PHYSICAL_SIZE
139 0 : .get_metric_with_label_values(&[&tenant_id, &shard_id])
140 0 : .unwrap();
141 0 :
142 0 : let heatmap_total_size_metric = SECONDARY_HEATMAP_TOTAL_SIZE
143 0 : .get_metric_with_label_values(&[&tenant_id, &shard_id])
144 0 : .unwrap();
145 0 :
146 0 : Arc::new(Self {
147 0 : tenant_shard_id,
148 0 : // todo: shall we make this a descendent of the
149 0 : // main cancellation token, or is it sufficient that
150 0 : // on shutdown we walk the tenants and fire their
151 0 : // individual cancellations?
152 0 : cancel: CancellationToken::new(),
153 0 : gate: Gate::default(),
154 0 :
155 0 : shard_identity,
156 0 : tenant_conf: std::sync::Mutex::new(tenant_conf),
157 0 :
158 0 : detail: std::sync::Mutex::new(SecondaryDetail::new(config.clone())),
159 0 :
160 0 : progress: std::sync::Mutex::default(),
161 0 :
162 0 : resident_size_metric,
163 0 : heatmap_total_size_metric,
164 0 : })
165 0 : }
166 :
167 0 : pub(crate) fn tenant_shard_id(&self) -> TenantShardId {
168 0 : self.tenant_shard_id
169 0 : }
170 :
171 0 : pub(crate) async fn shutdown(&self) {
172 0 : self.cancel.cancel();
173 0 :
174 0 : // Wait for any secondary downloader work to complete
175 0 : self.gate.close().await;
176 :
177 0 : self.validate_metrics();
178 0 :
179 0 : let tenant_id = self.tenant_shard_id.tenant_id.to_string();
180 0 : let shard_id = format!("{}", self.tenant_shard_id.shard_slug());
181 0 : let _ = SECONDARY_RESIDENT_PHYSICAL_SIZE.remove_label_values(&[&tenant_id, &shard_id]);
182 0 : let _ = SECONDARY_HEATMAP_TOTAL_SIZE.remove_label_values(&[&tenant_id, &shard_id]);
183 0 : }
184 :
185 0 : pub(crate) fn set_config(&self, config: &SecondaryLocationConfig) {
186 0 : self.detail.lock().unwrap().config = config.clone();
187 0 : }
188 :
189 0 : pub(crate) fn set_tenant_conf(&self, config: &TenantConfOpt) {
190 0 : *(self.tenant_conf.lock().unwrap()) = config.clone();
191 0 : }
192 :
193 : /// For API access: generate a LocationConfig equivalent to the one that would be used to
194 : /// create a Tenant in the same state. Do not use this in hot paths: it's for relatively
195 : /// rare external API calls, like a reconciliation at startup.
196 0 : pub(crate) fn get_location_conf(&self) -> models::LocationConfig {
197 0 : let conf = self.detail.lock().unwrap().config.clone();
198 0 :
199 0 : let conf = models::LocationConfigSecondary { warm: conf.warm };
200 0 :
201 0 : let tenant_conf = self.tenant_conf.lock().unwrap().clone();
202 0 : models::LocationConfig {
203 0 : mode: models::LocationConfigMode::Secondary,
204 0 : generation: None,
205 0 : secondary_conf: Some(conf),
206 0 : shard_number: self.tenant_shard_id.shard_number.0,
207 0 : shard_count: self.tenant_shard_id.shard_count.literal(),
208 0 : shard_stripe_size: self.shard_identity.stripe_size.0,
209 0 : tenant_conf: tenant_conf.into(),
210 0 : }
211 0 : }
212 :
213 0 : pub(crate) fn get_tenant_shard_id(&self) -> &TenantShardId {
214 0 : &self.tenant_shard_id
215 0 : }
216 :
217 0 : pub(crate) fn get_layers_for_eviction(self: &Arc<Self>) -> (DiskUsageEvictionInfo, usize) {
218 0 : self.detail.lock().unwrap().get_layers_for_eviction(self)
219 0 : }
220 :
221 : /// Cancellation safe, but on cancellation the eviction will go through
222 : #[instrument(skip_all, fields(tenant_id=%self.tenant_shard_id.tenant_id, shard_id=%self.tenant_shard_id.shard_slug(), timeline_id=%timeline_id, name=%name))]
223 : pub(crate) async fn evict_layer(self: &Arc<Self>, timeline_id: TimelineId, name: LayerName) {
224 : debug_assert_current_span_has_tenant_id();
225 :
226 : let guard = match self.gate.enter() {
227 : Ok(g) => g,
228 : Err(_) => {
229 : tracing::debug!("Dropping layer evictions, secondary tenant shutting down",);
230 : return;
231 : }
232 : };
233 :
234 : let now = SystemTime::now();
235 : tracing::info!("Evicting secondary layer");
236 :
237 : let this = self.clone();
238 :
239 : // spawn it to be cancellation safe
240 0 : tokio::task::spawn_blocking(move || {
241 0 : let _guard = guard;
242 0 :
243 0 : // Update the timeline's state. This does not have to be synchronized with
244 0 : // the download process, because:
245 0 : // - If downloader is racing with us to remove a file (e.g. because it is
246 0 : // removed from heatmap), then our mutual .remove() operations will both
247 0 : // succeed.
248 0 : // - If downloader is racing with us to download the object (this would require
249 0 : // multiple eviction iterations to race with multiple download iterations), then
250 0 : // if we remove it from the state, the worst that happens is the downloader
251 0 : // downloads it again before re-inserting, or we delete the file but it remains
252 0 : // in the state map (in which case it will be downloaded if this secondary
253 0 : // tenant transitions to attached and tries to access it)
254 0 : //
255 0 : // The important assumption here is that the secondary timeline state does not
256 0 : // have to 100% match what is on disk, because it's a best-effort warming
257 0 : // of the cache.
258 0 : let mut detail = this.detail.lock().unwrap();
259 0 : if let Some(removed) =
260 0 : detail.evict_layer(name, &timeline_id, now, &this.resident_size_metric)
261 0 : {
262 0 : // We might race with removal of the same layer during downloads, so finding the layer we
263 0 : // were trying to remove is optional. Only issue the disk I/O to remove it if we found it.
264 0 : removed.remove_blocking();
265 0 : }
266 0 : })
267 : .await
268 : .expect("secondary eviction should not have panicked");
269 : }
270 :
271 : /// Exhaustive check that incrementally updated metrics match the actual state.
272 : #[cfg(feature = "testing")]
273 0 : fn validate_metrics(&self) {
274 0 : let detail = self.detail.lock().unwrap();
275 0 : let resident_size = detail.total_resident_size();
276 0 :
277 0 : assert_eq!(resident_size, self.resident_size_metric.get());
278 0 : }
279 :
280 : #[cfg(not(feature = "testing"))]
281 : fn validate_metrics(&self) {
282 : // No-op in non-testing builds
283 : }
284 : }
285 :
286 : /// The SecondaryController is a pseudo-rpc client for administrative control of secondary mode downloads,
287 : /// and heatmap uploads. This is not a hot data path: it's used for:
288 : /// - Live migrations, where we want to ensure a migration destination has the freshest possible
289 : /// content before trying to cut over.
290 : /// - Tests, where we want to immediately upload/download for a particular tenant.
291 : ///
292 : /// In normal operations, outside of migrations, uploads & downloads are autonomous and not driven by this interface.
293 : pub struct SecondaryController {
294 : upload_req_tx: tokio::sync::mpsc::Sender<CommandRequest<UploadCommand>>,
295 : download_req_tx: tokio::sync::mpsc::Sender<CommandRequest<DownloadCommand>>,
296 : }
297 :
298 : impl SecondaryController {
299 0 : async fn dispatch<T>(
300 0 : &self,
301 0 : queue: &tokio::sync::mpsc::Sender<CommandRequest<T>>,
302 0 : payload: T,
303 0 : ) -> Result<(), SecondaryTenantError> {
304 0 : let (response_tx, response_rx) = tokio::sync::oneshot::channel();
305 0 :
306 0 : queue
307 0 : .send(CommandRequest {
308 0 : payload,
309 0 : response_tx,
310 0 : })
311 0 : .await
312 0 : .map_err(|_| SecondaryTenantError::ShuttingDown)?;
313 :
314 0 : let response = response_rx
315 0 : .await
316 0 : .map_err(|_| SecondaryTenantError::ShuttingDown)?;
317 :
318 0 : response.result
319 0 : }
320 :
321 0 : pub(crate) async fn upload_tenant(
322 0 : &self,
323 0 : tenant_shard_id: TenantShardId,
324 0 : ) -> Result<(), SecondaryTenantError> {
325 0 : self.dispatch(&self.upload_req_tx, UploadCommand::Upload(tenant_shard_id))
326 0 : .await
327 0 : }
328 0 : pub(crate) async fn download_tenant(
329 0 : &self,
330 0 : tenant_shard_id: TenantShardId,
331 0 : ) -> Result<(), SecondaryTenantError> {
332 0 : self.dispatch(
333 0 : &self.download_req_tx,
334 0 : DownloadCommand::Download(tenant_shard_id),
335 0 : )
336 0 : .await
337 0 : }
338 : }
339 :
340 : pub struct GlobalTasks {
341 : cancel: CancellationToken,
342 : uploader: JoinHandle<()>,
343 : downloader: JoinHandle<()>,
344 : }
345 :
346 : impl GlobalTasks {
347 : /// Caller is responsible for requesting shutdown via the cancellation token that was
348 : /// passed to [`spawn_tasks`].
349 : ///
350 : /// # Panics
351 : ///
352 : /// This method panics if that token is not cancelled.
353 : /// This is low-risk because we're calling this during process shutdown, so, a panic
354 : /// will be informative but not cause undue downtime.
355 0 : pub async fn wait(self) {
356 0 : let Self {
357 0 : cancel,
358 0 : uploader,
359 0 : downloader,
360 0 : } = self;
361 0 : assert!(
362 0 : cancel.is_cancelled(),
363 0 : "must cancel cancellation token, otherwise the tasks will not shut down"
364 : );
365 :
366 0 : let (uploader, downloader) = futures::future::join(uploader, downloader).await;
367 0 : uploader.expect(
368 0 : "unreachable: exit_on_panic_or_error would catch the panic and exit the process",
369 0 : );
370 0 : downloader.expect(
371 0 : "unreachable: exit_on_panic_or_error would catch the panic and exit the process",
372 0 : );
373 0 : }
374 : }
375 :
376 0 : pub fn spawn_tasks(
377 0 : tenant_manager: Arc<TenantManager>,
378 0 : remote_storage: GenericRemoteStorage,
379 0 : background_jobs_can_start: Barrier,
380 0 : cancel: CancellationToken,
381 0 : ) -> (SecondaryController, GlobalTasks) {
382 0 : let mgr_clone = tenant_manager.clone();
383 0 : let storage_clone = remote_storage.clone();
384 0 : let bg_jobs_clone = background_jobs_can_start.clone();
385 0 :
386 0 : let (download_req_tx, download_req_rx) =
387 0 : tokio::sync::mpsc::channel::<CommandRequest<DownloadCommand>>(16);
388 0 : let (upload_req_tx, upload_req_rx) =
389 0 : tokio::sync::mpsc::channel::<CommandRequest<UploadCommand>>(16);
390 0 :
391 0 : let cancel_clone = cancel.clone();
392 0 : let downloader = BACKGROUND_RUNTIME.spawn(task_mgr::exit_on_panic_or_error(
393 0 : "secondary tenant downloads",
394 0 : async move {
395 0 : downloader_task(
396 0 : mgr_clone,
397 0 : storage_clone,
398 0 : download_req_rx,
399 0 : bg_jobs_clone,
400 0 : cancel_clone,
401 0 : RequestContext::new(
402 0 : TaskKind::SecondaryDownloads,
403 0 : crate::context::DownloadBehavior::Download,
404 0 : ),
405 0 : )
406 0 : .await;
407 0 : anyhow::Ok(())
408 0 : },
409 0 : ));
410 0 :
411 0 : let cancel_clone = cancel.clone();
412 0 : let uploader = BACKGROUND_RUNTIME.spawn(task_mgr::exit_on_panic_or_error(
413 0 : "heatmap uploads",
414 0 : async move {
415 0 : heatmap_uploader_task(
416 0 : tenant_manager,
417 0 : remote_storage,
418 0 : upload_req_rx,
419 0 : background_jobs_can_start,
420 0 : cancel_clone,
421 0 : )
422 0 : .await;
423 0 : anyhow::Ok(())
424 0 : },
425 0 : ));
426 0 :
427 0 : (
428 0 : SecondaryController {
429 0 : upload_req_tx,
430 0 : download_req_tx,
431 0 : },
432 0 : GlobalTasks {
433 0 : cancel,
434 0 : uploader,
435 0 : downloader,
436 0 : },
437 0 : )
438 0 : }
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