Line data Source code
1 : use std::collections::HashMap;
2 : use std::fmt::Display;
3 : use std::sync::Arc;
4 : use std::time::Duration;
5 :
6 : use anyhow::{anyhow, Context};
7 : use futures::future::Either;
8 : use futures::StreamExt;
9 : use pageserver_api::shard::ShardIdentity;
10 : use postgres_backend::{CopyStreamHandlerEnd, PostgresBackend};
11 : use postgres_ffi::waldecoder::WalDecodeError;
12 : use postgres_ffi::{get_current_timestamp, waldecoder::WalStreamDecoder};
13 : use pq_proto::{BeMessage, InterpretedWalRecordsBody, WalSndKeepAlive};
14 : use tokio::io::{AsyncRead, AsyncWrite};
15 : use tokio::sync::mpsc::error::SendError;
16 : use tokio::task::JoinHandle;
17 : use tokio::time::MissedTickBehavior;
18 : use tracing::{error, info, info_span, Instrument};
19 : use utils::critical;
20 : use utils::lsn::Lsn;
21 : use utils::postgres_client::Compression;
22 : use utils::postgres_client::InterpretedFormat;
23 : use wal_decoder::models::{InterpretedWalRecord, InterpretedWalRecords};
24 : use wal_decoder::wire_format::ToWireFormat;
25 :
26 : use crate::metrics::WAL_READERS;
27 : use crate::send_wal::{EndWatchView, WalSenderGuard};
28 : use crate::timeline::WalResidentTimeline;
29 : use crate::wal_reader_stream::{StreamingWalReader, WalBytes};
30 :
31 : /// Identifier used to differentiate between senders of the same
32 : /// shard.
33 : ///
34 : /// In the steady state there's only one, but two pageservers may
35 : /// temporarily have the same shard attached and attempt to ingest
36 : /// WAL for it. See also [`ShardSenderId`].
37 : #[derive(Hash, Eq, PartialEq, Copy, Clone)]
38 : struct SenderId(u8);
39 :
40 : impl SenderId {
41 3 : fn first() -> Self {
42 3 : SenderId(0)
43 3 : }
44 :
45 2 : fn next(&self) -> Self {
46 2 : SenderId(self.0.checked_add(1).expect("few senders"))
47 2 : }
48 : }
49 :
50 : #[derive(Hash, Eq, PartialEq)]
51 : struct ShardSenderId {
52 : shard: ShardIdentity,
53 : sender_id: SenderId,
54 : }
55 :
56 : impl Display for ShardSenderId {
57 0 : fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
58 0 : write!(f, "{}{}", self.sender_id.0, self.shard.shard_slug())
59 0 : }
60 : }
61 :
62 : impl ShardSenderId {
63 852 : fn new(shard: ShardIdentity, sender_id: SenderId) -> Self {
64 852 : ShardSenderId { shard, sender_id }
65 852 : }
66 :
67 0 : fn shard(&self) -> ShardIdentity {
68 0 : self.shard
69 0 : }
70 : }
71 :
72 : /// Shard-aware fan-out interpreted record reader.
73 : /// Reads WAL from disk, decodes it, intepretets it, and sends
74 : /// it to any [`InterpretedWalSender`] connected to it.
75 : /// Each [`InterpretedWalSender`] corresponds to one shard
76 : /// and gets interpreted records concerning that shard only.
77 : pub(crate) struct InterpretedWalReader {
78 : wal_stream: StreamingWalReader,
79 : shard_senders: HashMap<ShardIdentity, smallvec::SmallVec<[ShardSenderState; 1]>>,
80 : shard_notification_rx: Option<tokio::sync::mpsc::UnboundedReceiver<AttachShardNotification>>,
81 : state: Arc<std::sync::RwLock<InterpretedWalReaderState>>,
82 : pg_version: u32,
83 : }
84 :
85 : /// A handle for [`InterpretedWalReader`] which allows for interacting with it
86 : /// when it runs as a separate tokio task.
87 : #[derive(Debug)]
88 : pub(crate) struct InterpretedWalReaderHandle {
89 : join_handle: JoinHandle<Result<(), InterpretedWalReaderError>>,
90 : state: Arc<std::sync::RwLock<InterpretedWalReaderState>>,
91 : shard_notification_tx: tokio::sync::mpsc::UnboundedSender<AttachShardNotification>,
92 : }
93 :
94 : struct ShardSenderState {
95 : sender_id: SenderId,
96 : tx: tokio::sync::mpsc::Sender<Batch>,
97 : next_record_lsn: Lsn,
98 : }
99 :
100 : /// State of [`InterpretedWalReader`] visible outside of the task running it.
101 : #[derive(Debug)]
102 : pub(crate) enum InterpretedWalReaderState {
103 : Running { current_position: Lsn },
104 : Done,
105 : }
106 :
107 : pub(crate) struct Batch {
108 : wal_end_lsn: Lsn,
109 : available_wal_end_lsn: Lsn,
110 : records: InterpretedWalRecords,
111 : }
112 :
113 : #[derive(thiserror::Error, Debug)]
114 : pub enum InterpretedWalReaderError {
115 : /// Handler initiates the end of streaming.
116 : #[error("decode error: {0}")]
117 : Decode(#[from] WalDecodeError),
118 : #[error("read or interpret error: {0}")]
119 : ReadOrInterpret(#[from] anyhow::Error),
120 : #[error("wal stream closed")]
121 : WalStreamClosed,
122 : }
123 :
124 : enum CurrentPositionUpdate {
125 : Reset(Lsn),
126 : NotReset(Lsn),
127 : }
128 :
129 : impl CurrentPositionUpdate {
130 0 : fn current_position(&self) -> Lsn {
131 0 : match self {
132 0 : CurrentPositionUpdate::Reset(lsn) => *lsn,
133 0 : CurrentPositionUpdate::NotReset(lsn) => *lsn,
134 : }
135 0 : }
136 : }
137 :
138 : impl InterpretedWalReaderState {
139 4 : fn current_position(&self) -> Option<Lsn> {
140 4 : match self {
141 : InterpretedWalReaderState::Running {
142 2 : current_position, ..
143 2 : } => Some(*current_position),
144 2 : InterpretedWalReaderState::Done => None,
145 : }
146 4 : }
147 :
148 : // Reset the current position of the WAL reader if the requested starting position
149 : // of the new shard is smaller than the current value.
150 3 : fn maybe_reset(&mut self, new_shard_start_pos: Lsn) -> CurrentPositionUpdate {
151 3 : match self {
152 : InterpretedWalReaderState::Running {
153 3 : current_position, ..
154 3 : } => {
155 3 : if new_shard_start_pos < *current_position {
156 2 : *current_position = new_shard_start_pos;
157 2 : CurrentPositionUpdate::Reset(*current_position)
158 : } else {
159 1 : CurrentPositionUpdate::NotReset(*current_position)
160 : }
161 : }
162 : InterpretedWalReaderState::Done => {
163 0 : panic!("maybe_reset called on finished reader")
164 : }
165 : }
166 3 : }
167 : }
168 :
169 : pub(crate) struct AttachShardNotification {
170 : shard_id: ShardIdentity,
171 : sender: tokio::sync::mpsc::Sender<Batch>,
172 : start_pos: Lsn,
173 : }
174 :
175 : impl InterpretedWalReader {
176 : /// Spawn the reader in a separate tokio task and return a handle
177 2 : pub(crate) fn spawn(
178 2 : wal_stream: StreamingWalReader,
179 2 : start_pos: Lsn,
180 2 : tx: tokio::sync::mpsc::Sender<Batch>,
181 2 : shard: ShardIdentity,
182 2 : pg_version: u32,
183 2 : appname: &Option<String>,
184 2 : ) -> InterpretedWalReaderHandle {
185 2 : let state = Arc::new(std::sync::RwLock::new(InterpretedWalReaderState::Running {
186 2 : current_position: start_pos,
187 2 : }));
188 2 :
189 2 : let (shard_notification_tx, shard_notification_rx) = tokio::sync::mpsc::unbounded_channel();
190 :
191 2 : let reader = InterpretedWalReader {
192 2 : wal_stream,
193 2 : shard_senders: HashMap::from([(
194 2 : shard,
195 2 : smallvec::smallvec![ShardSenderState {
196 0 : sender_id: SenderId::first(),
197 0 : tx,
198 0 : next_record_lsn: start_pos,
199 0 : }],
200 : )]),
201 2 : shard_notification_rx: Some(shard_notification_rx),
202 2 : state: state.clone(),
203 2 : pg_version,
204 2 : };
205 2 :
206 2 : let metric = WAL_READERS
207 2 : .get_metric_with_label_values(&["task", appname.as_deref().unwrap_or("safekeeper")])
208 2 : .unwrap();
209 :
210 2 : let join_handle = tokio::task::spawn(
211 2 : async move {
212 2 : metric.inc();
213 2 : scopeguard::defer! {
214 2 : metric.dec();
215 2 : }
216 2 :
217 2 : reader
218 2 : .run_impl(start_pos)
219 2 : .await
220 0 : .inspect_err(|err| critical!("failed to read WAL record: {err:?}"))
221 0 : }
222 2 : .instrument(info_span!("interpreted wal reader")),
223 : );
224 :
225 2 : InterpretedWalReaderHandle {
226 2 : join_handle,
227 2 : state,
228 2 : shard_notification_tx,
229 2 : }
230 2 : }
231 :
232 : /// Construct the reader without spawning anything
233 : /// Callers should drive the future returned by [`Self::run`].
234 0 : pub(crate) fn new(
235 0 : wal_stream: StreamingWalReader,
236 0 : start_pos: Lsn,
237 0 : tx: tokio::sync::mpsc::Sender<Batch>,
238 0 : shard: ShardIdentity,
239 0 : pg_version: u32,
240 0 : ) -> InterpretedWalReader {
241 0 : let state = Arc::new(std::sync::RwLock::new(InterpretedWalReaderState::Running {
242 0 : current_position: start_pos,
243 0 : }));
244 0 :
245 0 : InterpretedWalReader {
246 0 : wal_stream,
247 0 : shard_senders: HashMap::from([(
248 0 : shard,
249 0 : smallvec::smallvec![ShardSenderState {
250 0 : sender_id: SenderId::first(),
251 0 : tx,
252 0 : next_record_lsn: start_pos,
253 0 : }],
254 : )]),
255 0 : shard_notification_rx: None,
256 0 : state: state.clone(),
257 0 : pg_version,
258 0 : }
259 0 : }
260 :
261 : /// Entry point for future (polling) based wal reader.
262 0 : pub(crate) async fn run(
263 0 : self,
264 0 : start_pos: Lsn,
265 0 : appname: &Option<String>,
266 0 : ) -> Result<(), CopyStreamHandlerEnd> {
267 0 : let metric = WAL_READERS
268 0 : .get_metric_with_label_values(&["future", appname.as_deref().unwrap_or("safekeeper")])
269 0 : .unwrap();
270 0 :
271 0 : metric.inc();
272 0 : scopeguard::defer! {
273 0 : metric.dec();
274 0 : }
275 :
276 0 : if let Err(err) = self.run_impl(start_pos).await {
277 0 : critical!("failed to read WAL record: {err:?}");
278 : } else {
279 0 : info!("interpreted wal reader exiting");
280 : }
281 :
282 0 : Err(CopyStreamHandlerEnd::Other(anyhow!(
283 0 : "interpreted wal reader finished"
284 0 : )))
285 0 : }
286 :
287 : /// Send interpreted WAL to one or more [`InterpretedWalSender`]s
288 : /// Stops when an error is encountered or when the [`InterpretedWalReaderHandle`]
289 : /// goes out of scope.
290 2 : async fn run_impl(mut self, start_pos: Lsn) -> Result<(), InterpretedWalReaderError> {
291 2 : let defer_state = self.state.clone();
292 2 : scopeguard::defer! {
293 2 : *defer_state.write().unwrap() = InterpretedWalReaderState::Done;
294 2 : }
295 2 :
296 2 : let mut wal_decoder = WalStreamDecoder::new(start_pos, self.pg_version);
297 :
298 : loop {
299 44 : tokio::select! {
300 : // Main branch for reading WAL and forwarding it
301 44 : wal_or_reset = self.wal_stream.next() => {
302 39 : let wal = wal_or_reset.map(|wor| wor.get_wal().expect("reset handled in select branch below"));
303 : let WalBytes {
304 39 : wal,
305 39 : wal_start_lsn: _,
306 39 : wal_end_lsn,
307 39 : available_wal_end_lsn,
308 39 : } = match wal {
309 39 : Some(some) => some.map_err(InterpretedWalReaderError::ReadOrInterpret)?,
310 : None => {
311 : // [`StreamingWalReader::next`] is an endless stream of WAL.
312 : // It shouldn't ever finish unless it panicked or became internally
313 : // inconsistent.
314 0 : return Result::Err(InterpretedWalReaderError::WalStreamClosed);
315 : }
316 : };
317 :
318 39 : wal_decoder.feed_bytes(&wal);
319 39 :
320 39 : // Deserialize and interpret WAL records from this batch of WAL.
321 39 : // Interpreted records for each shard are collected separately.
322 39 : let shard_ids = self.shard_senders.keys().copied().collect::<Vec<_>>();
323 39 : let mut records_by_sender: HashMap<ShardSenderId, Vec<InterpretedWalRecord>> = HashMap::new();
324 39 : let mut max_next_record_lsn = None;
325 635 : while let Some((next_record_lsn, recdata)) = wal_decoder.poll_decode()?
326 : {
327 596 : assert!(next_record_lsn.is_aligned());
328 596 : max_next_record_lsn = Some(next_record_lsn);
329 :
330 596 : let interpreted = InterpretedWalRecord::from_bytes_filtered(
331 596 : recdata,
332 596 : &shard_ids,
333 596 : next_record_lsn,
334 596 : self.pg_version,
335 596 : )
336 596 : .with_context(|| "Failed to interpret WAL")?;
337 :
338 1391 : for (shard, record) in interpreted {
339 795 : if record.is_empty() {
340 199 : continue;
341 596 : }
342 596 :
343 596 : let mut states_iter = self.shard_senders
344 596 : .get(&shard)
345 596 : .expect("keys collected above")
346 596 : .iter()
347 992 : .filter(|state| record.next_record_lsn > state.next_record_lsn)
348 596 : .peekable();
349 986 : while let Some(state) = states_iter.next() {
350 787 : let shard_sender_id = ShardSenderId::new(shard, state.sender_id);
351 787 :
352 787 : // The most commont case is one sender per shard. Peek and break to avoid the
353 787 : // clone in that situation.
354 787 : if states_iter.peek().is_none() {
355 397 : records_by_sender.entry(shard_sender_id).or_default().push(record);
356 397 : break;
357 390 : } else {
358 390 : records_by_sender.entry(shard_sender_id).or_default().push(record.clone());
359 390 : }
360 : }
361 : }
362 : }
363 :
364 39 : let max_next_record_lsn = match max_next_record_lsn {
365 39 : Some(lsn) => lsn,
366 0 : None => { continue; }
367 : };
368 :
369 : // Update the current position such that new receivers can decide
370 : // whether to attach to us or spawn a new WAL reader.
371 39 : match &mut *self.state.write().unwrap() {
372 39 : InterpretedWalReaderState::Running { current_position, .. } => {
373 39 : *current_position = max_next_record_lsn;
374 39 : },
375 : InterpretedWalReaderState::Done => {
376 0 : unreachable!()
377 : }
378 : }
379 :
380 : // Send interpreted records downstream. Anything that has already been seen
381 : // by a shard is filtered out.
382 39 : let mut shard_senders_to_remove = Vec::new();
383 91 : for (shard, states) in &mut self.shard_senders {
384 130 : for state in states {
385 78 : if max_next_record_lsn <= state.next_record_lsn {
386 13 : continue;
387 65 : }
388 65 :
389 65 : let shard_sender_id = ShardSenderId::new(*shard, state.sender_id);
390 65 : let records = records_by_sender.remove(&shard_sender_id).unwrap_or_default();
391 65 :
392 65 : let batch = InterpretedWalRecords {
393 65 : records,
394 65 : next_record_lsn: Some(max_next_record_lsn),
395 65 : };
396 :
397 65 : let res = state.tx.send(Batch {
398 65 : wal_end_lsn,
399 65 : available_wal_end_lsn,
400 65 : records: batch,
401 65 : }).await;
402 :
403 65 : if res.is_err() {
404 0 : shard_senders_to_remove.push(shard_sender_id);
405 65 : } else {
406 65 : state.next_record_lsn = max_next_record_lsn;
407 65 : }
408 : }
409 : }
410 :
411 : // Clean up any shard senders that have dropped out.
412 : // This is inefficient, but such events are rare (connection to PS termination)
413 : // and the number of subscriptions on the same shards very small (only one
414 : // for the steady state).
415 39 : for to_remove in shard_senders_to_remove {
416 0 : let shard_senders = self.shard_senders.get_mut(&to_remove.shard()).expect("saw it above");
417 0 : if let Some(idx) = shard_senders.iter().position(|s| s.sender_id == to_remove.sender_id) {
418 0 : shard_senders.remove(idx);
419 0 : tracing::info!("Removed shard sender {}", to_remove);
420 0 : }
421 :
422 0 : if shard_senders.is_empty() {
423 0 : self.shard_senders.remove(&to_remove.shard());
424 0 : }
425 : }
426 : },
427 : // Listen for new shards that want to attach to this reader.
428 : // If the reader is not running as a task, then this is not supported
429 : // (see the pending branch below).
430 44 : notification = match self.shard_notification_rx.as_mut() {
431 44 : Some(rx) => Either::Left(rx.recv()),
432 0 : None => Either::Right(std::future::pending())
433 : } => {
434 3 : if let Some(n) = notification {
435 3 : let AttachShardNotification { shard_id, sender, start_pos } = n;
436 3 :
437 3 : // Update internal and external state, then reset the WAL stream
438 3 : // if required.
439 3 : let senders = self.shard_senders.entry(shard_id).or_default();
440 3 : let new_sender_id = match senders.last() {
441 2 : Some(sender) => sender.sender_id.next(),
442 1 : None => SenderId::first()
443 : };
444 :
445 3 : senders.push(ShardSenderState { sender_id: new_sender_id, tx: sender, next_record_lsn: start_pos});
446 3 :
447 3 : // If the shard is subscribing below the current position the we need
448 3 : // to update the cursor that tracks where we are at in the WAL
449 3 : // ([`Self::state`]) and reset the WAL stream itself
450 3 : // (`[Self::wal_stream`]). This must be done atomically from the POV of
451 3 : // anything outside the select statement.
452 3 : let position_reset = self.state.write().unwrap().maybe_reset(start_pos);
453 3 : match position_reset {
454 2 : CurrentPositionUpdate::Reset(to) => {
455 2 : self.wal_stream.reset(to).await;
456 2 : wal_decoder = WalStreamDecoder::new(to, self.pg_version);
457 : },
458 1 : CurrentPositionUpdate::NotReset(_) => {}
459 : };
460 :
461 3 : tracing::info!(
462 0 : "Added shard sender {} with start_pos={} current_pos={}",
463 0 : ShardSenderId::new(shard_id, new_sender_id), start_pos, position_reset.current_position()
464 : );
465 0 : }
466 : }
467 : }
468 : }
469 0 : }
470 : }
471 :
472 : impl InterpretedWalReaderHandle {
473 : /// Fan-out the reader by attaching a new shard to it
474 3 : pub(crate) fn fanout(
475 3 : &self,
476 3 : shard_id: ShardIdentity,
477 3 : sender: tokio::sync::mpsc::Sender<Batch>,
478 3 : start_pos: Lsn,
479 3 : ) -> Result<(), SendError<AttachShardNotification>> {
480 3 : self.shard_notification_tx.send(AttachShardNotification {
481 3 : shard_id,
482 3 : sender,
483 3 : start_pos,
484 3 : })
485 3 : }
486 :
487 : /// Get the current WAL position of the reader
488 4 : pub(crate) fn current_position(&self) -> Option<Lsn> {
489 4 : self.state.read().unwrap().current_position()
490 4 : }
491 :
492 4 : pub(crate) fn abort(&self) {
493 4 : self.join_handle.abort()
494 4 : }
495 : }
496 :
497 : impl Drop for InterpretedWalReaderHandle {
498 2 : fn drop(&mut self) {
499 2 : tracing::info!("Aborting interpreted wal reader");
500 2 : self.abort()
501 2 : }
502 : }
503 :
504 : pub(crate) struct InterpretedWalSender<'a, IO> {
505 : pub(crate) format: InterpretedFormat,
506 : pub(crate) compression: Option<Compression>,
507 : pub(crate) appname: Option<String>,
508 :
509 : pub(crate) tli: WalResidentTimeline,
510 : pub(crate) start_lsn: Lsn,
511 :
512 : pub(crate) pgb: &'a mut PostgresBackend<IO>,
513 : pub(crate) end_watch_view: EndWatchView,
514 : pub(crate) wal_sender_guard: Arc<WalSenderGuard>,
515 : pub(crate) rx: tokio::sync::mpsc::Receiver<Batch>,
516 : }
517 :
518 : impl<IO: AsyncRead + AsyncWrite + Unpin> InterpretedWalSender<'_, IO> {
519 : /// Send interpreted WAL records over the network.
520 : /// Also manages keep-alives if nothing was sent for a while.
521 0 : pub(crate) async fn run(mut self) -> Result<(), CopyStreamHandlerEnd> {
522 0 : let mut keepalive_ticker = tokio::time::interval(Duration::from_secs(1));
523 0 : keepalive_ticker.set_missed_tick_behavior(MissedTickBehavior::Skip);
524 0 : keepalive_ticker.reset();
525 0 :
526 0 : let mut wal_position = self.start_lsn;
527 :
528 : loop {
529 0 : tokio::select! {
530 0 : batch = self.rx.recv() => {
531 0 : let batch = match batch {
532 0 : Some(b) => b,
533 : None => {
534 0 : return Result::Err(
535 0 : CopyStreamHandlerEnd::Other(anyhow!("Interpreted WAL reader exited early"))
536 0 : );
537 : }
538 : };
539 :
540 0 : wal_position = batch.wal_end_lsn;
541 :
542 0 : let buf = batch
543 0 : .records
544 0 : .to_wire(self.format, self.compression)
545 0 : .await
546 0 : .with_context(|| "Failed to serialize interpreted WAL")
547 0 : .map_err(CopyStreamHandlerEnd::from)?;
548 :
549 : // Reset the keep alive ticker since we are sending something
550 : // over the wire now.
551 0 : keepalive_ticker.reset();
552 0 :
553 0 : self.pgb
554 0 : .write_message(&BeMessage::InterpretedWalRecords(InterpretedWalRecordsBody {
555 0 : streaming_lsn: batch.wal_end_lsn.0,
556 0 : commit_lsn: batch.available_wal_end_lsn.0,
557 0 : data: &buf,
558 0 : })).await?;
559 : }
560 : // Send a periodic keep alive when the connection has been idle for a while.
561 : // Since we've been idle, also check if we can stop streaming.
562 0 : _ = keepalive_ticker.tick() => {
563 0 : if let Some(remote_consistent_lsn) = self.wal_sender_guard
564 0 : .walsenders()
565 0 : .get_ws_remote_consistent_lsn(self.wal_sender_guard.id())
566 : {
567 0 : if self.tli.should_walsender_stop(remote_consistent_lsn).await {
568 : // Stop streaming if the receivers are caught up and
569 : // there's no active compute. This causes the loop in
570 : // [`crate::send_interpreted_wal::InterpretedWalSender::run`]
571 : // to exit and terminate the WAL stream.
572 0 : break;
573 0 : }
574 0 : }
575 :
576 0 : self.pgb
577 0 : .write_message(&BeMessage::KeepAlive(WalSndKeepAlive {
578 0 : wal_end: self.end_watch_view.get().0,
579 0 : timestamp: get_current_timestamp(),
580 0 : request_reply: true,
581 0 : }))
582 0 : .await?;
583 : },
584 : }
585 : }
586 :
587 0 : Err(CopyStreamHandlerEnd::ServerInitiated(format!(
588 0 : "ending streaming to {:?} at {}, receiver is caughtup and there is no computes",
589 0 : self.appname, wal_position,
590 0 : )))
591 0 : }
592 : }
593 : #[cfg(test)]
594 : mod tests {
595 : use std::{collections::HashMap, str::FromStr, time::Duration};
596 :
597 : use pageserver_api::shard::{ShardIdentity, ShardStripeSize};
598 : use postgres_ffi::MAX_SEND_SIZE;
599 : use tokio::sync::mpsc::error::TryRecvError;
600 : use utils::{
601 : id::{NodeId, TenantTimelineId},
602 : lsn::Lsn,
603 : shard::{ShardCount, ShardNumber},
604 : };
605 :
606 : use crate::{
607 : send_interpreted_wal::{Batch, InterpretedWalReader},
608 : test_utils::Env,
609 : wal_reader_stream::StreamingWalReader,
610 : };
611 :
612 : #[tokio::test]
613 1 : async fn test_interpreted_wal_reader_fanout() {
614 1 : let _ = env_logger::builder().is_test(true).try_init();
615 1 :
616 1 : const SIZE: usize = 8 * 1024;
617 1 : const MSG_COUNT: usize = 200;
618 1 : const PG_VERSION: u32 = 17;
619 1 : const SHARD_COUNT: u8 = 2;
620 1 :
621 1 : let start_lsn = Lsn::from_str("0/149FD18").unwrap();
622 1 : let env = Env::new(true).unwrap();
623 1 : let tli = env
624 1 : .make_timeline(NodeId(1), TenantTimelineId::generate(), start_lsn)
625 1 : .await
626 1 : .unwrap();
627 1 :
628 1 : let resident_tli = tli.wal_residence_guard().await.unwrap();
629 1 : let end_watch = Env::write_wal(tli, start_lsn, SIZE, MSG_COUNT, None)
630 1 : .await
631 1 : .unwrap();
632 1 : let end_pos = end_watch.get();
633 1 :
634 1 : tracing::info!("Doing first round of reads ...");
635 1 :
636 1 : let streaming_wal_reader = StreamingWalReader::new(
637 1 : resident_tli,
638 1 : None,
639 1 : start_lsn,
640 1 : end_pos,
641 1 : end_watch,
642 1 : MAX_SEND_SIZE,
643 1 : );
644 1 :
645 1 : let shard_0 = ShardIdentity::new(
646 1 : ShardNumber(0),
647 1 : ShardCount(SHARD_COUNT),
648 1 : ShardStripeSize::default(),
649 1 : )
650 1 : .unwrap();
651 1 :
652 1 : let shard_1 = ShardIdentity::new(
653 1 : ShardNumber(1),
654 1 : ShardCount(SHARD_COUNT),
655 1 : ShardStripeSize::default(),
656 1 : )
657 1 : .unwrap();
658 1 :
659 1 : let mut shards = HashMap::new();
660 1 :
661 3 : for shard_number in 0..SHARD_COUNT {
662 2 : let shard_id = ShardIdentity::new(
663 2 : ShardNumber(shard_number),
664 2 : ShardCount(SHARD_COUNT),
665 2 : ShardStripeSize::default(),
666 2 : )
667 2 : .unwrap();
668 2 : let (tx, rx) = tokio::sync::mpsc::channel::<Batch>(MSG_COUNT * 2);
669 2 : shards.insert(shard_id, (Some(tx), Some(rx)));
670 2 : }
671 1 :
672 1 : let shard_0_tx = shards.get_mut(&shard_0).unwrap().0.take().unwrap();
673 1 : let mut shard_0_rx = shards.get_mut(&shard_0).unwrap().1.take().unwrap();
674 1 :
675 1 : let handle = InterpretedWalReader::spawn(
676 1 : streaming_wal_reader,
677 1 : start_lsn,
678 1 : shard_0_tx,
679 1 : shard_0,
680 1 : PG_VERSION,
681 1 : &Some("pageserver".to_string()),
682 1 : );
683 1 :
684 1 : tracing::info!("Reading all WAL with only shard 0 attached ...");
685 1 :
686 1 : let mut shard_0_interpreted_records = Vec::new();
687 13 : while let Some(batch) = shard_0_rx.recv().await {
688 13 : shard_0_interpreted_records.push(batch.records);
689 13 : if batch.wal_end_lsn == batch.available_wal_end_lsn {
690 1 : break;
691 12 : }
692 1 : }
693 1 :
694 1 : let shard_1_tx = shards.get_mut(&shard_1).unwrap().0.take().unwrap();
695 1 : let mut shard_1_rx = shards.get_mut(&shard_1).unwrap().1.take().unwrap();
696 1 :
697 1 : tracing::info!("Attaching shard 1 to the reader at start of WAL");
698 1 : handle.fanout(shard_1, shard_1_tx, start_lsn).unwrap();
699 1 :
700 1 : tracing::info!("Reading all WAL with shard 0 and shard 1 attached ...");
701 1 :
702 1 : let mut shard_1_interpreted_records = Vec::new();
703 13 : while let Some(batch) = shard_1_rx.recv().await {
704 13 : shard_1_interpreted_records.push(batch.records);
705 13 : if batch.wal_end_lsn == batch.available_wal_end_lsn {
706 1 : break;
707 12 : }
708 1 : }
709 1 :
710 1 : // This test uses logical messages. Those only go to shard 0. Check that the
711 1 : // filtering worked and shard 1 did not get any.
712 1 : assert!(shard_1_interpreted_records
713 1 : .iter()
714 13 : .all(|recs| recs.records.is_empty()));
715 1 :
716 1 : // Shard 0 should not receive anything more since the reader is
717 1 : // going through wal that it has already processed.
718 1 : let res = shard_0_rx.try_recv();
719 1 : if let Ok(ref ok) = res {
720 1 : tracing::error!(
721 1 : "Shard 0 received batch: wal_end_lsn={} available_wal_end_lsn={}",
722 1 : ok.wal_end_lsn,
723 1 : ok.available_wal_end_lsn
724 1 : );
725 1 : }
726 1 : assert!(matches!(res, Err(TryRecvError::Empty)));
727 1 :
728 1 : // Check that the next records lsns received by the two shards match up.
729 1 : let shard_0_next_lsns = shard_0_interpreted_records
730 1 : .iter()
731 13 : .map(|recs| recs.next_record_lsn)
732 1 : .collect::<Vec<_>>();
733 1 : let shard_1_next_lsns = shard_1_interpreted_records
734 1 : .iter()
735 13 : .map(|recs| recs.next_record_lsn)
736 1 : .collect::<Vec<_>>();
737 1 : assert_eq!(shard_0_next_lsns, shard_1_next_lsns);
738 1 :
739 1 : handle.abort();
740 1 : let mut done = false;
741 2 : for _ in 0..5 {
742 2 : if handle.current_position().is_none() {
743 1 : done = true;
744 1 : break;
745 1 : }
746 1 : tokio::time::sleep(Duration::from_millis(1)).await;
747 1 : }
748 1 :
749 1 : assert!(done);
750 1 : }
751 :
752 : #[tokio::test]
753 1 : async fn test_interpreted_wal_reader_same_shard_fanout() {
754 1 : let _ = env_logger::builder().is_test(true).try_init();
755 1 :
756 1 : const SIZE: usize = 8 * 1024;
757 1 : const MSG_COUNT: usize = 200;
758 1 : const PG_VERSION: u32 = 17;
759 1 : const SHARD_COUNT: u8 = 2;
760 1 :
761 1 : let start_lsn = Lsn::from_str("0/149FD18").unwrap();
762 1 : let env = Env::new(true).unwrap();
763 1 : let tli = env
764 1 : .make_timeline(NodeId(1), TenantTimelineId::generate(), start_lsn)
765 1 : .await
766 1 : .unwrap();
767 1 :
768 1 : let resident_tli = tli.wal_residence_guard().await.unwrap();
769 1 : let mut next_record_lsns = Vec::default();
770 1 : let end_watch =
771 1 : Env::write_wal(tli, start_lsn, SIZE, MSG_COUNT, Some(&mut next_record_lsns))
772 1 : .await
773 1 : .unwrap();
774 1 : let end_pos = end_watch.get();
775 1 :
776 1 : let streaming_wal_reader = StreamingWalReader::new(
777 1 : resident_tli,
778 1 : None,
779 1 : start_lsn,
780 1 : end_pos,
781 1 : end_watch,
782 1 : MAX_SEND_SIZE,
783 1 : );
784 1 :
785 1 : let shard_0 = ShardIdentity::new(
786 1 : ShardNumber(0),
787 1 : ShardCount(SHARD_COUNT),
788 1 : ShardStripeSize::default(),
789 1 : )
790 1 : .unwrap();
791 1 :
792 1 : struct Sender {
793 1 : tx: Option<tokio::sync::mpsc::Sender<Batch>>,
794 1 : rx: tokio::sync::mpsc::Receiver<Batch>,
795 1 : shard: ShardIdentity,
796 1 : start_lsn: Lsn,
797 1 : received_next_record_lsns: Vec<Lsn>,
798 1 : }
799 1 :
800 1 : impl Sender {
801 3 : fn new(start_lsn: Lsn, shard: ShardIdentity) -> Self {
802 3 : let (tx, rx) = tokio::sync::mpsc::channel::<Batch>(MSG_COUNT * 2);
803 3 : Self {
804 3 : tx: Some(tx),
805 3 : rx,
806 3 : shard,
807 3 : start_lsn,
808 3 : received_next_record_lsns: Vec::default(),
809 3 : }
810 3 : }
811 1 : }
812 1 :
813 1 : assert!(next_record_lsns.len() > 7);
814 1 : let start_lsns = vec![
815 1 : next_record_lsns[5],
816 1 : next_record_lsns[1],
817 1 : next_record_lsns[3],
818 1 : ];
819 1 : let mut senders = start_lsns
820 1 : .into_iter()
821 3 : .map(|lsn| Sender::new(lsn, shard_0))
822 1 : .collect::<Vec<_>>();
823 1 :
824 1 : let first_sender = senders.first_mut().unwrap();
825 1 : let handle = InterpretedWalReader::spawn(
826 1 : streaming_wal_reader,
827 1 : first_sender.start_lsn,
828 1 : first_sender.tx.take().unwrap(),
829 1 : first_sender.shard,
830 1 : PG_VERSION,
831 1 : &Some("pageserver".to_string()),
832 1 : );
833 1 :
834 2 : for sender in senders.iter_mut().skip(1) {
835 2 : handle
836 2 : .fanout(sender.shard, sender.tx.take().unwrap(), sender.start_lsn)
837 2 : .unwrap();
838 2 : }
839 1 :
840 3 : for sender in senders.iter_mut() {
841 1 : loop {
842 39 : let batch = sender.rx.recv().await.unwrap();
843 39 : tracing::info!(
844 1 : "Sender with start_lsn={} received batch ending at {} with {} records",
845 0 : sender.start_lsn,
846 0 : batch.wal_end_lsn,
847 0 : batch.records.records.len()
848 1 : );
849 1 :
850 627 : for rec in batch.records.records {
851 588 : sender.received_next_record_lsns.push(rec.next_record_lsn);
852 588 : }
853 1 :
854 39 : if batch.wal_end_lsn == batch.available_wal_end_lsn {
855 3 : break;
856 36 : }
857 1 : }
858 1 : }
859 1 :
860 1 : handle.abort();
861 1 : let mut done = false;
862 2 : for _ in 0..5 {
863 2 : if handle.current_position().is_none() {
864 1 : done = true;
865 1 : break;
866 1 : }
867 1 : tokio::time::sleep(Duration::from_millis(1)).await;
868 1 : }
869 1 :
870 1 : assert!(done);
871 1 :
872 4 : for sender in senders {
873 3 : tracing::info!(
874 1 : "Validating records received by sender with start_lsn={}",
875 1 : sender.start_lsn
876 1 : );
877 1 :
878 3 : assert!(sender.received_next_record_lsns.is_sorted());
879 3 : let expected = next_record_lsns
880 3 : .iter()
881 600 : .filter(|lsn| **lsn > sender.start_lsn)
882 3 : .copied()
883 3 : .collect::<Vec<_>>();
884 3 : assert_eq!(sender.received_next_record_lsns, expected);
885 1 : }
886 1 : }
887 : }
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