Line data Source code
1 : use std::{collections::hash_map::Entry, fs, sync::Arc};
2 :
3 : use anyhow::Context;
4 : use camino::Utf8PathBuf;
5 : use tracing::{error, info, info_span};
6 : use utils::{fs_ext, id::TimelineId, lsn::Lsn};
7 :
8 : use crate::{
9 : context::RequestContext,
10 : import_datadir,
11 : tenant::{CreateTimelineIdempotency, Tenant, TimelineOrOffloaded},
12 : };
13 :
14 : use super::Timeline;
15 :
16 : /// A timeline with some of its files on disk, being initialized.
17 : /// This struct ensures the atomicity of the timeline init: it's either properly created and inserted into pageserver's memory, or
18 : /// its local files are removed. If we crash while this class exists, then the timeline's local
19 : /// state is cleaned up during [`Tenant::clean_up_timelines`], because the timeline's content isn't in remote storage.
20 : ///
21 : /// The caller is responsible for proper timeline data filling before the final init.
22 : #[must_use]
23 : pub struct UninitializedTimeline<'t> {
24 : pub(crate) owning_tenant: &'t Tenant,
25 : timeline_id: TimelineId,
26 : raw_timeline: Option<(Arc<Timeline>, TimelineCreateGuard<'t>)>,
27 : }
28 :
29 : impl<'t> UninitializedTimeline<'t> {
30 408 : pub(crate) fn new(
31 408 : owning_tenant: &'t Tenant,
32 408 : timeline_id: TimelineId,
33 408 : raw_timeline: Option<(Arc<Timeline>, TimelineCreateGuard<'t>)>,
34 408 : ) -> Self {
35 408 : Self {
36 408 : owning_tenant,
37 408 : timeline_id,
38 408 : raw_timeline,
39 408 : }
40 408 : }
41 :
42 : /// Finish timeline creation: insert it into the Tenant's timelines map
43 : ///
44 : /// This function launches the flush loop if not already done.
45 : ///
46 : /// The caller is responsible for activating the timeline (function `.activate()`).
47 400 : pub(crate) fn finish_creation(mut self) -> anyhow::Result<Arc<Timeline>> {
48 400 : let timeline_id = self.timeline_id;
49 400 : let tenant_shard_id = self.owning_tenant.tenant_shard_id;
50 400 :
51 400 : if self.raw_timeline.is_none() {
52 0 : return Err(anyhow::anyhow!(
53 0 : "No timeline for initialization found for {tenant_shard_id}/{timeline_id}"
54 0 : ));
55 400 : }
56 400 :
57 400 : // Check that the caller initialized disk_consistent_lsn
58 400 : let new_disk_consistent_lsn = self
59 400 : .raw_timeline
60 400 : .as_ref()
61 400 : .expect("checked above")
62 400 : .0
63 400 : .get_disk_consistent_lsn();
64 400 :
65 400 : anyhow::ensure!(
66 400 : new_disk_consistent_lsn.is_valid(),
67 0 : "new timeline {tenant_shard_id}/{timeline_id} has invalid disk_consistent_lsn"
68 : );
69 :
70 400 : let mut timelines = self.owning_tenant.timelines.lock().unwrap();
71 400 : match timelines.entry(timeline_id) {
72 0 : Entry::Occupied(_) => anyhow::bail!(
73 0 : "Found freshly initialized timeline {tenant_shard_id}/{timeline_id} in the tenant map"
74 0 : ),
75 400 : Entry::Vacant(v) => {
76 400 : // after taking here should be no fallible operations, because the drop guard will not
77 400 : // cleanup after and would block for example the tenant deletion
78 400 : let (new_timeline, _create_guard) =
79 400 : self.raw_timeline.take().expect("already checked");
80 400 :
81 400 : v.insert(Arc::clone(&new_timeline));
82 400 :
83 400 : new_timeline.maybe_spawn_flush_loop();
84 400 :
85 400 : Ok(new_timeline)
86 : }
87 : }
88 400 : }
89 :
90 : /// Prepares timeline data by loading it from the basebackup archive.
91 0 : pub(crate) async fn import_basebackup_from_tar(
92 0 : self,
93 0 : tenant: Arc<Tenant>,
94 0 : copyin_read: &mut (impl tokio::io::AsyncRead + Send + Sync + Unpin),
95 0 : base_lsn: Lsn,
96 0 : broker_client: storage_broker::BrokerClientChannel,
97 0 : ctx: &RequestContext,
98 0 : ) -> anyhow::Result<Arc<Timeline>> {
99 0 : let raw_timeline = self.raw_timeline()?;
100 :
101 0 : import_datadir::import_basebackup_from_tar(raw_timeline, copyin_read, base_lsn, ctx)
102 0 : .await
103 0 : .context("Failed to import basebackup")?;
104 :
105 : // Flush the new layer files to disk, before we make the timeline as available to
106 : // the outside world.
107 : //
108 : // Flush loop needs to be spawned in order to be able to flush.
109 0 : raw_timeline.maybe_spawn_flush_loop();
110 0 :
111 0 : fail::fail_point!("before-checkpoint-new-timeline", |_| {
112 0 : anyhow::bail!("failpoint before-checkpoint-new-timeline");
113 0 : });
114 :
115 0 : raw_timeline
116 0 : .freeze_and_flush()
117 0 : .await
118 0 : .context("Failed to flush after basebackup import")?;
119 :
120 : // All the data has been imported. Insert the Timeline into the tenant's timelines map
121 0 : let tl = self.finish_creation()?;
122 0 : tl.activate(tenant, broker_client, None, ctx);
123 0 : Ok(tl)
124 0 : }
125 :
126 182 : pub(crate) fn raw_timeline(&self) -> anyhow::Result<&Arc<Timeline>> {
127 182 : Ok(&self
128 182 : .raw_timeline
129 182 : .as_ref()
130 182 : .with_context(|| {
131 0 : format!(
132 0 : "No raw timeline {}/{} found",
133 0 : self.owning_tenant.tenant_shard_id, self.timeline_id
134 0 : )
135 182 : })?
136 : .0)
137 182 : }
138 : }
139 :
140 : impl Drop for UninitializedTimeline<'_> {
141 406 : fn drop(&mut self) {
142 406 : if let Some((_, create_guard)) = self.raw_timeline.take() {
143 6 : let _entered = info_span!("drop_uninitialized_timeline", tenant_id = %self.owning_tenant.tenant_shard_id.tenant_id, shard_id = %self.owning_tenant.tenant_shard_id.shard_slug(), timeline_id = %self.timeline_id).entered();
144 6 : // This is unusual, but can happen harmlessly if the pageserver is stopped while
145 6 : // creating a timeline.
146 6 : info!("Timeline got dropped without initializing, cleaning its files");
147 6 : cleanup_timeline_directory(create_guard);
148 400 : }
149 406 : }
150 : }
151 :
152 6 : pub(crate) fn cleanup_timeline_directory(create_guard: TimelineCreateGuard) {
153 6 : let timeline_path = &create_guard.timeline_path;
154 6 : match fs_ext::ignore_absent_files(|| fs::remove_dir_all(timeline_path)) {
155 : Ok(()) => {
156 6 : info!("Timeline dir {timeline_path:?} removed successfully")
157 : }
158 0 : Err(e) => {
159 0 : error!("Failed to clean up uninitialized timeline directory {timeline_path:?}: {e:?}")
160 : }
161 : }
162 : // Having cleaned up, we can release this TimelineId in `[Tenant::timelines_creating]` to allow other
163 : // timeline creation attempts under this TimelineId to proceed
164 6 : drop(create_guard);
165 6 : }
166 :
167 : /// A guard for timeline creations in process: as long as this object exists, the timeline ID
168 : /// is kept in `[Tenant::timelines_creating]` to exclude concurrent attempts to create the same timeline.
169 : #[must_use]
170 : pub(crate) struct TimelineCreateGuard<'t> {
171 : owning_tenant: &'t Tenant,
172 : timeline_id: TimelineId,
173 : pub(crate) timeline_path: Utf8PathBuf,
174 : pub(crate) idempotency: CreateTimelineIdempotency,
175 : }
176 :
177 : /// Errors when acquiring exclusive access to a timeline ID for creation
178 0 : #[derive(thiserror::Error, Debug)]
179 : pub(crate) enum TimelineExclusionError {
180 : #[error("Already exists")]
181 : AlreadyExists {
182 : existing: TimelineOrOffloaded,
183 : arg: CreateTimelineIdempotency,
184 : },
185 : #[error("Already creating")]
186 : AlreadyCreating,
187 :
188 : // e.g. I/O errors, or some failure deep in postgres initdb
189 : #[error(transparent)]
190 : Other(#[from] anyhow::Error),
191 : }
192 :
193 : impl<'t> TimelineCreateGuard<'t> {
194 414 : pub(crate) fn new(
195 414 : owning_tenant: &'t Tenant,
196 414 : timeline_id: TimelineId,
197 414 : timeline_path: Utf8PathBuf,
198 414 : idempotency: CreateTimelineIdempotency,
199 414 : allow_offloaded: bool,
200 414 : ) -> Result<Self, TimelineExclusionError> {
201 414 : // Lock order: this is the only place we take both locks. During drop() we only
202 414 : // lock creating_timelines
203 414 : let timelines = owning_tenant.timelines.lock().unwrap();
204 414 : let timelines_offloaded = owning_tenant.timelines_offloaded.lock().unwrap();
205 414 : let mut creating_timelines: std::sync::MutexGuard<
206 414 : '_,
207 414 : std::collections::HashSet<TimelineId>,
208 414 : > = owning_tenant.timelines_creating.lock().unwrap();
209 :
210 414 : if let Some(existing) = timelines.get(&timeline_id) {
211 2 : return Err(TimelineExclusionError::AlreadyExists {
212 2 : existing: TimelineOrOffloaded::Timeline(existing.clone()),
213 2 : arg: idempotency,
214 2 : });
215 412 : }
216 412 : if !allow_offloaded {
217 412 : if let Some(existing) = timelines_offloaded.get(&timeline_id) {
218 0 : return Err(TimelineExclusionError::AlreadyExists {
219 0 : existing: TimelineOrOffloaded::Offloaded(existing.clone()),
220 0 : arg: idempotency,
221 0 : });
222 412 : }
223 0 : }
224 412 : if creating_timelines.contains(&timeline_id) {
225 0 : return Err(TimelineExclusionError::AlreadyCreating);
226 412 : }
227 412 : creating_timelines.insert(timeline_id);
228 412 : Ok(Self {
229 412 : owning_tenant,
230 412 : timeline_id,
231 412 : timeline_path,
232 412 : idempotency,
233 412 : })
234 414 : }
235 : }
236 :
237 : impl Drop for TimelineCreateGuard<'_> {
238 410 : fn drop(&mut self) {
239 410 : self.owning_tenant
240 410 : .timelines_creating
241 410 : .lock()
242 410 : .unwrap()
243 410 : .remove(&self.timeline_id);
244 410 : }
245 : }
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