Line data Source code
1 : use std::collections::HashMap;
2 : use std::sync::Arc;
3 :
4 : use crate::checks::{list_timeline_blobs, BlobDataParseResult, RemoteTimelineBlobData};
5 : use crate::metadata_stream::{stream_tenant_shards, stream_tenant_timelines};
6 : use crate::{
7 : download_object_to_file_s3, init_remote, init_remote_s3, BucketConfig, NodeKind, RootTarget,
8 : TenantShardTimelineId,
9 : };
10 : use anyhow::Context;
11 : use async_stream::stream;
12 : use aws_sdk_s3::Client;
13 : use camino::Utf8PathBuf;
14 : use futures::{StreamExt, TryStreamExt};
15 : use pageserver::tenant::remote_timeline_client::index::LayerFileMetadata;
16 : use pageserver::tenant::storage_layer::LayerName;
17 : use pageserver::tenant::IndexPart;
18 : use pageserver_api::shard::TenantShardId;
19 : use remote_storage::GenericRemoteStorage;
20 : use utils::generation::Generation;
21 : use utils::id::TenantId;
22 :
23 : pub struct SnapshotDownloader {
24 : s3_client: Arc<Client>,
25 : s3_root: RootTarget,
26 : bucket_config: BucketConfig,
27 : tenant_id: TenantId,
28 : output_path: Utf8PathBuf,
29 : concurrency: usize,
30 : }
31 :
32 : impl SnapshotDownloader {
33 0 : pub async fn new(
34 0 : bucket_config: BucketConfig,
35 0 : tenant_id: TenantId,
36 0 : output_path: Utf8PathBuf,
37 0 : concurrency: usize,
38 0 : ) -> anyhow::Result<Self> {
39 0 : let (s3_client, s3_root) =
40 0 : init_remote_s3(bucket_config.clone(), NodeKind::Pageserver).await?;
41 0 : Ok(Self {
42 0 : s3_client,
43 0 : s3_root,
44 0 : bucket_config,
45 0 : tenant_id,
46 0 : output_path,
47 0 : concurrency,
48 0 : })
49 0 : }
50 :
51 0 : async fn download_layer(
52 0 : &self,
53 0 : ttid: TenantShardTimelineId,
54 0 : layer_name: LayerName,
55 0 : layer_metadata: LayerFileMetadata,
56 0 : ) -> anyhow::Result<(LayerName, LayerFileMetadata)> {
57 0 : // Note this is local as in a local copy of S3 data, not local as in the pageserver's local format. They use
58 0 : // different layer names (remote-style has the generation suffix)
59 0 : let local_path = self.output_path.join(format!(
60 0 : "{}/timelines/{}/{}{}",
61 0 : ttid.tenant_shard_id,
62 0 : ttid.timeline_id,
63 0 : layer_name,
64 0 : layer_metadata.generation.get_suffix()
65 0 : ));
66 0 :
67 0 : // We should only be called for layers that are owned by the input TTID
68 0 : assert_eq!(layer_metadata.shard, ttid.tenant_shard_id.to_index());
69 :
70 : // Assumption: we always write layer files atomically, and layer files are immutable. Therefore if the file
71 : // already exists on local disk, we assume it is fully correct and skip it.
72 0 : if tokio::fs::try_exists(&local_path).await? {
73 0 : tracing::debug!("{} already exists", local_path);
74 0 : return Ok((layer_name, layer_metadata));
75 : } else {
76 0 : tracing::debug!("{} requires download...", local_path);
77 :
78 0 : let timeline_root = self.s3_root.timeline_root(&ttid);
79 0 : let remote_layer_path = format!(
80 0 : "{}{}{}",
81 0 : timeline_root.prefix_in_bucket,
82 0 : layer_name,
83 0 : layer_metadata.generation.get_suffix()
84 0 : );
85 :
86 : // List versions: the object might be deleted.
87 0 : let versions = self
88 0 : .s3_client
89 0 : .list_object_versions()
90 0 : .bucket(self.bucket_config.bucket.clone())
91 0 : .prefix(&remote_layer_path)
92 0 : .send()
93 0 : .await?;
94 0 : let Some(version) = versions.versions.as_ref().and_then(|v| v.first()) else {
95 0 : return Err(anyhow::anyhow!("No versions found for {remote_layer_path}"));
96 : };
97 0 : download_object_to_file_s3(
98 0 : &self.s3_client,
99 0 : &self.bucket_config.bucket,
100 0 : &remote_layer_path,
101 0 : version.version_id.as_deref(),
102 0 : &local_path,
103 0 : )
104 0 : .await?;
105 :
106 0 : tracing::debug!("Downloaded successfully to {local_path}");
107 : }
108 :
109 0 : Ok((layer_name, layer_metadata))
110 0 : }
111 :
112 : /// Download many layers belonging to the same TTID, with some concurrency
113 0 : async fn download_layers(
114 0 : &self,
115 0 : ttid: TenantShardTimelineId,
116 0 : layers: Vec<(LayerName, LayerFileMetadata)>,
117 0 : ) -> anyhow::Result<()> {
118 0 : let layer_count = layers.len();
119 0 : tracing::info!("Downloading {} layers for timeline {ttid}...", layer_count);
120 0 : let layers_stream = stream! {
121 0 : for (layer_name, layer_metadata) in layers {
122 0 : yield self.download_layer(ttid, layer_name, layer_metadata);
123 0 : }
124 0 : };
125 0 :
126 0 : tokio::fs::create_dir_all(self.output_path.join(format!(
127 0 : "{}/timelines/{}",
128 0 : ttid.tenant_shard_id, ttid.timeline_id
129 0 : )))
130 0 : .await?;
131 :
132 0 : let layer_results = layers_stream.buffered(self.concurrency);
133 0 : let mut layer_results = std::pin::pin!(layer_results);
134 0 :
135 0 : let mut err = None;
136 0 : let mut download_count = 0;
137 0 : while let Some(i) = layer_results.next().await {
138 0 : download_count += 1;
139 0 : match i {
140 0 : Ok((layer_name, layer_metadata)) => {
141 0 : tracing::info!(
142 0 : "[{download_count}/{layer_count}] OK: {} bytes {ttid} {}",
143 : layer_metadata.file_size,
144 : layer_name
145 : );
146 : }
147 0 : Err(e) => {
148 0 : // Warn and continue: we will download what we can
149 0 : tracing::warn!("Download error: {e}");
150 0 : err = Some(e);
151 : }
152 : }
153 : }
154 0 : if let Some(e) = err {
155 0 : tracing::warn!("Some errors occurred downloading {ttid} layers, last error: {e}");
156 0 : Err(e)
157 : } else {
158 0 : Ok(())
159 : }
160 0 : }
161 :
162 0 : async fn download_timeline(
163 0 : &self,
164 0 : ttid: TenantShardTimelineId,
165 0 : index_part: Box<IndexPart>,
166 0 : index_part_generation: Generation,
167 0 : ancestor_layers: &mut HashMap<TenantShardTimelineId, HashMap<LayerName, LayerFileMetadata>>,
168 0 : ) -> anyhow::Result<()> {
169 0 : let index_bytes = serde_json::to_string(&index_part).unwrap();
170 0 :
171 0 : let layers = index_part
172 0 : .layer_metadata
173 0 : .into_iter()
174 0 : .filter_map(|(layer_name, layer_metadata)| {
175 0 : if layer_metadata.shard.shard_count != ttid.tenant_shard_id.shard_count {
176 : // Accumulate ancestor layers for later download
177 0 : let ancestor_ttid = TenantShardTimelineId::new(
178 0 : TenantShardId {
179 0 : tenant_id: ttid.tenant_shard_id.tenant_id,
180 0 : shard_number: layer_metadata.shard.shard_number,
181 0 : shard_count: layer_metadata.shard.shard_count,
182 0 : },
183 0 : ttid.timeline_id,
184 0 : );
185 0 : let ancestor_ttid_layers = ancestor_layers.entry(ancestor_ttid).or_default();
186 : use std::collections::hash_map::Entry;
187 0 : match ancestor_ttid_layers.entry(layer_name) {
188 0 : Entry::Occupied(entry) => {
189 0 : // Descendent shards that reference a layer from an ancestor should always have matching metadata,
190 0 : // as their siblings, because it is read atomically during a shard split.
191 0 : assert_eq!(entry.get(), &layer_metadata);
192 : }
193 0 : Entry::Vacant(entry) => {
194 0 : entry.insert(layer_metadata);
195 0 : }
196 : }
197 0 : None
198 : } else {
199 0 : Some((layer_name, layer_metadata))
200 : }
201 0 : })
202 0 : .collect();
203 :
204 0 : let download_result = self.download_layers(ttid, layers).await;
205 :
206 : // Write index last, once all the layers it references are downloaded
207 0 : let local_index_path = self.output_path.join(format!(
208 0 : "{}/timelines/{}/index_part.json{}",
209 0 : ttid.tenant_shard_id,
210 0 : ttid.timeline_id,
211 0 : index_part_generation.get_suffix()
212 0 : ));
213 0 : tokio::fs::write(&local_index_path, index_bytes)
214 0 : .await
215 0 : .context("writing index")?;
216 :
217 0 : download_result
218 0 : }
219 :
220 0 : pub async fn download(&self) -> anyhow::Result<()> {
221 0 : let (remote_client, target) =
222 0 : init_remote(self.bucket_config.clone(), NodeKind::Pageserver).await?;
223 :
224 : // Generate a stream of TenantShardId
225 0 : let shards = stream_tenant_shards(&remote_client, &target, self.tenant_id).await?;
226 0 : let shards: Vec<TenantShardId> = shards.try_collect().await?;
227 :
228 : // Only read from shards that have the highest count: avoids redundantly downloading
229 : // from ancestor shards.
230 0 : let Some(shard_count) = shards.iter().map(|s| s.shard_count).max() else {
231 0 : anyhow::bail!("No shards found");
232 : };
233 :
234 : // We will build a collection of layers in anccestor shards to download (this will only
235 : // happen if this tenant has been split at some point)
236 0 : let mut ancestor_layers: HashMap<
237 0 : TenantShardTimelineId,
238 0 : HashMap<LayerName, LayerFileMetadata>,
239 0 : > = Default::default();
240 :
241 0 : for shard in shards.into_iter().filter(|s| s.shard_count == shard_count) {
242 : // Generate a stream of TenantTimelineId
243 0 : let timelines = stream_tenant_timelines(&remote_client, &target, shard).await?;
244 :
245 : // Generate a stream of S3TimelineBlobData
246 0 : async fn load_timeline_index(
247 0 : remote_client: &GenericRemoteStorage,
248 0 : target: &RootTarget,
249 0 : ttid: TenantShardTimelineId,
250 0 : ) -> anyhow::Result<(TenantShardTimelineId, RemoteTimelineBlobData)> {
251 0 : let data = list_timeline_blobs(remote_client, ttid, target).await?;
252 0 : Ok((ttid, data))
253 0 : }
254 0 : let timelines =
255 0 : timelines.map_ok(|ttid| load_timeline_index(&remote_client, &target, ttid));
256 0 : let mut timelines = std::pin::pin!(timelines.try_buffered(8));
257 :
258 0 : while let Some(i) = timelines.next().await {
259 0 : let (ttid, data) = i?;
260 0 : match data.blob_data {
261 : BlobDataParseResult::Parsed {
262 0 : index_part,
263 0 : index_part_generation,
264 0 : s3_layers: _,
265 0 : } => {
266 0 : self.download_timeline(
267 0 : ttid,
268 0 : index_part,
269 0 : index_part_generation,
270 0 : &mut ancestor_layers,
271 0 : )
272 0 : .await
273 0 : .context("Downloading timeline")?;
274 : }
275 0 : BlobDataParseResult::Relic => {}
276 : BlobDataParseResult::Incorrect { .. } => {
277 0 : tracing::error!("Bad metadata in timeline {ttid}");
278 : }
279 : };
280 : }
281 : }
282 :
283 0 : for (ttid, layers) in ancestor_layers.into_iter() {
284 0 : tracing::info!(
285 0 : "Downloading {} layers from ancestor timeline {ttid}...",
286 0 : layers.len()
287 : );
288 :
289 0 : self.download_layers(ttid, layers.into_iter().collect())
290 0 : .await?;
291 : }
292 :
293 0 : Ok(())
294 0 : }
295 : }
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