Line data Source code
1 : use std::ffi::OsStr;
2 : use std::path::{Path, PathBuf};
3 : use std::process::Command;
4 : use std::time::{Duration, Instant};
5 :
6 : use anyhow::{bail, ensure};
7 : use camino_tempfile::{Utf8TempDir, tempdir};
8 : use log::*;
9 : use postgres::Client;
10 : use postgres::types::PgLsn;
11 : use postgres_ffi::{
12 : WAL_SEGMENT_SIZE, XLOG_BLCKSZ, XLOG_SIZE_OF_XLOG_LONG_PHD, XLOG_SIZE_OF_XLOG_RECORD,
13 : XLOG_SIZE_OF_XLOG_SHORT_PHD,
14 : };
15 :
16 : macro_rules! xlog_utils_test {
17 : ($version:ident) => {
18 : #[path = "."]
19 : mod $version {
20 : #[allow(unused_imports)]
21 : pub use postgres_ffi::$version::wal_craft_test_export::*;
22 : #[allow(clippy::duplicate_mod)]
23 : #[cfg(test)]
24 : mod xlog_utils_test;
25 : }
26 : };
27 : }
28 :
29 : postgres_ffi::for_all_postgres_versions! { xlog_utils_test }
30 :
31 : pub struct Conf {
32 : pub pg_version: u32,
33 : pub pg_distrib_dir: PathBuf,
34 : pub datadir: PathBuf,
35 : }
36 :
37 : pub struct PostgresServer {
38 : process: std::process::Child,
39 : _unix_socket_dir: Utf8TempDir,
40 : client_config: postgres::Config,
41 : }
42 :
43 : pub static REQUIRED_POSTGRES_CONFIG: [&str; 4] = [
44 : "wal_keep_size=50MB", // Ensure old WAL is not removed
45 : "shared_preload_libraries=neon", // can only be loaded at startup
46 : // Disable background processes as much as possible
47 : "wal_writer_delay=10s",
48 : "autovacuum=off",
49 : ];
50 :
51 : impl Conf {
52 108 : pub fn pg_distrib_dir(&self) -> anyhow::Result<PathBuf> {
53 108 : let path = self.pg_distrib_dir.clone();
54 108 :
55 108 : #[allow(clippy::manual_range_patterns)]
56 108 : match self.pg_version {
57 108 : 14 | 15 | 16 | 17 => Ok(path.join(format!("v{}", self.pg_version))),
58 0 : _ => bail!("Unsupported postgres version: {}", self.pg_version),
59 : }
60 108 : }
61 :
62 36 : fn pg_bin_dir(&self) -> anyhow::Result<PathBuf> {
63 36 : Ok(self.pg_distrib_dir()?.join("bin"))
64 36 : }
65 :
66 72 : fn pg_lib_dir(&self) -> anyhow::Result<PathBuf> {
67 72 : Ok(self.pg_distrib_dir()?.join("lib"))
68 72 : }
69 :
70 204 : pub fn wal_dir(&self) -> PathBuf {
71 204 : self.datadir.join("pg_wal")
72 204 : }
73 :
74 36 : fn new_pg_command(&self, command: impl AsRef<Path>) -> anyhow::Result<Command> {
75 36 : let path = self.pg_bin_dir()?.join(command);
76 36 : ensure!(path.exists(), "Command {:?} does not exist", path);
77 36 : let mut cmd = Command::new(path);
78 36 : cmd.env_clear()
79 36 : .env("LD_LIBRARY_PATH", self.pg_lib_dir()?)
80 36 : .env("DYLD_LIBRARY_PATH", self.pg_lib_dir()?)
81 36 : .env(
82 36 : "ASAN_OPTIONS",
83 36 : std::env::var("ASAN_OPTIONS").unwrap_or_default(),
84 36 : )
85 36 : .env(
86 36 : "UBSAN_OPTIONS",
87 36 : std::env::var("UBSAN_OPTIONS").unwrap_or_default(),
88 36 : );
89 36 : Ok(cmd)
90 36 : }
91 :
92 12 : pub fn initdb(&self) -> anyhow::Result<()> {
93 12 : if let Some(parent) = self.datadir.parent() {
94 12 : info!("Pre-creating parent directory {:?}", parent);
95 : // Tests may be run concurrently and there may be a race to create `test_output/`.
96 : // std::fs::create_dir_all is guaranteed to have no races with another thread creating directories.
97 12 : std::fs::create_dir_all(parent)?;
98 0 : }
99 12 : info!(
100 12 : "Running initdb in {:?} with user \"postgres\"",
101 : self.datadir
102 : );
103 12 : let output = self
104 12 : .new_pg_command("initdb")?
105 12 : .arg("--pgdata")
106 12 : .arg(&self.datadir)
107 12 : .args(["--username", "postgres", "--no-instructions", "--no-sync"])
108 12 : .output()?;
109 12 : debug!("initdb output: {:?}", output);
110 12 : ensure!(
111 12 : output.status.success(),
112 0 : "initdb failed, stdout and stderr follow:\n{}{}",
113 0 : String::from_utf8_lossy(&output.stdout),
114 0 : String::from_utf8_lossy(&output.stderr),
115 : );
116 12 : Ok(())
117 12 : }
118 :
119 12 : pub fn start_server(&self) -> anyhow::Result<PostgresServer> {
120 12 : info!("Starting Postgres server in {:?}", self.datadir);
121 12 : let unix_socket_dir = tempdir()?; // We need a directory with a short name for Unix socket (up to 108 symbols)
122 12 : let unix_socket_dir_path = unix_socket_dir.path().to_owned();
123 12 : let server_process = self
124 12 : .new_pg_command("postgres")?
125 12 : .args(["-c", "listen_addresses="])
126 12 : .arg("-k")
127 12 : .arg(&unix_socket_dir_path)
128 12 : .arg("-D")
129 12 : .arg(&self.datadir)
130 48 : .args(REQUIRED_POSTGRES_CONFIG.iter().flat_map(|cfg| ["-c", cfg]))
131 12 : .spawn()?;
132 12 : let server = PostgresServer {
133 12 : process: server_process,
134 12 : _unix_socket_dir: unix_socket_dir,
135 12 : client_config: {
136 12 : let mut c = postgres::Config::new();
137 12 : c.host_path(&unix_socket_dir_path);
138 12 : c.user("postgres");
139 12 : c.connect_timeout(Duration::from_millis(10000));
140 12 : c
141 12 : },
142 12 : };
143 12 : Ok(server)
144 12 : }
145 :
146 12 : pub fn pg_waldump(
147 12 : &self,
148 12 : first_segment_name: &OsStr,
149 12 : last_segment_name: &OsStr,
150 12 : ) -> anyhow::Result<std::process::Output> {
151 12 : let first_segment_file = self.datadir.join(first_segment_name);
152 12 : let last_segment_file = self.datadir.join(last_segment_name);
153 12 : info!(
154 12 : "Running pg_waldump for {} .. {}",
155 12 : first_segment_file.display(),
156 12 : last_segment_file.display()
157 : );
158 12 : let output = self
159 12 : .new_pg_command("pg_waldump")?
160 12 : .args([&first_segment_file, &last_segment_file])
161 12 : .output()?;
162 12 : debug!("waldump output: {:?}", output);
163 12 : Ok(output)
164 12 : }
165 : }
166 :
167 : impl PostgresServer {
168 12 : pub fn connect_with_timeout(&self) -> anyhow::Result<Client> {
169 12 : let retry_until = Instant::now() + *self.client_config.get_connect_timeout().unwrap();
170 25 : while Instant::now() < retry_until {
171 25 : if let Ok(client) = self.client_config.connect(postgres::NoTls) {
172 12 : return Ok(client);
173 13 : }
174 13 : std::thread::sleep(Duration::from_millis(100));
175 : }
176 0 : bail!("Connection timed out");
177 12 : }
178 :
179 12 : pub fn kill(mut self) {
180 12 : self.process.kill().unwrap();
181 12 : self.process.wait().unwrap();
182 12 : }
183 : }
184 :
185 : impl Drop for PostgresServer {
186 12 : fn drop(&mut self) {
187 12 : match self.process.try_wait() {
188 12 : Ok(Some(_)) => return,
189 : Ok(None) => {
190 0 : warn!("Server was not terminated, will be killed");
191 : }
192 0 : Err(e) => {
193 0 : error!("Unable to get status of the server: {}, will be killed", e);
194 : }
195 : }
196 0 : let _ = self.process.kill();
197 12 : }
198 : }
199 :
200 : pub trait PostgresClientExt: postgres::GenericClient {
201 24 : fn pg_current_wal_insert_lsn(&mut self) -> anyhow::Result<PgLsn> {
202 24 : Ok(self
203 24 : .query_one("SELECT pg_current_wal_insert_lsn()", &[])?
204 24 : .get(0))
205 24 : }
206 0 : fn pg_current_wal_flush_lsn(&mut self) -> anyhow::Result<PgLsn> {
207 0 : Ok(self
208 0 : .query_one("SELECT pg_current_wal_flush_lsn()", &[])?
209 0 : .get(0))
210 0 : }
211 : }
212 :
213 : impl<C: postgres::GenericClient> PostgresClientExt for C {}
214 :
215 12 : pub fn ensure_server_config(client: &mut impl postgres::GenericClient) -> anyhow::Result<()> {
216 12 : client.execute("create extension if not exists neon_test_utils", &[])?;
217 :
218 12 : let wal_keep_size: String = client.query_one("SHOW wal_keep_size", &[])?.get(0);
219 12 : ensure!(wal_keep_size == "50MB");
220 12 : let wal_writer_delay: String = client.query_one("SHOW wal_writer_delay", &[])?.get(0);
221 12 : ensure!(wal_writer_delay == "10s");
222 12 : let autovacuum: String = client.query_one("SHOW autovacuum", &[])?.get(0);
223 12 : ensure!(autovacuum == "off");
224 :
225 12 : let wal_segment_size = client.query_one(
226 12 : "select cast(setting as bigint) as setting, unit \
227 12 : from pg_settings where name = 'wal_segment_size'",
228 12 : &[],
229 12 : )?;
230 12 : ensure!(
231 12 : wal_segment_size.get::<_, String>("unit") == "B",
232 0 : "Unexpected wal_segment_size unit"
233 : );
234 12 : ensure!(
235 12 : wal_segment_size.get::<_, i64>("setting") == WAL_SEGMENT_SIZE as i64,
236 0 : "Unexpected wal_segment_size in bytes"
237 : );
238 :
239 12 : Ok(())
240 12 : }
241 :
242 : pub trait Crafter {
243 : const NAME: &'static str;
244 :
245 : /// Generates WAL using the client `client`. Returns a vector of some valid
246 : /// "interesting" intermediate LSNs which one may start reading from.
247 : /// test_end_of_wal uses this to check various starting points.
248 : ///
249 : /// Note that postgres is generally keen about writing some WAL. While we
250 : /// try to disable it (autovacuum, big wal_writer_delay, etc) it is always
251 : /// possible, e.g. xl_running_xacts are dumped each 15s. So checks about
252 : /// stable WAL end would be flaky unless postgres is shut down. For this
253 : /// reason returning potential end of WAL here is pointless. Most of the
254 : /// time this doesn't happen though, so it is reasonable to create needed
255 : /// WAL structure and immediately kill postgres like test_end_of_wal does.
256 : fn craft(client: &mut impl postgres::GenericClient) -> anyhow::Result<Vec<PgLsn>>;
257 : }
258 :
259 : /// Wraps some WAL craft function, providing current LSN to it before the
260 : /// insertion and flushing WAL afterwards. Also pushes initial LSN to the
261 : /// result.
262 12 : fn craft_internal<C: postgres::GenericClient>(
263 12 : client: &mut C,
264 12 : f: impl Fn(&mut C, PgLsn) -> anyhow::Result<Vec<PgLsn>>,
265 12 : ) -> anyhow::Result<Vec<PgLsn>> {
266 12 : ensure_server_config(client)?;
267 :
268 12 : let initial_lsn = client.pg_current_wal_insert_lsn()?;
269 12 : info!("LSN initial = {}", initial_lsn);
270 :
271 12 : let mut intermediate_lsns = f(client, initial_lsn)?;
272 12 : if !intermediate_lsns.starts_with(&[initial_lsn]) {
273 12 : intermediate_lsns.insert(0, initial_lsn);
274 12 : }
275 :
276 : // Some records may be not flushed, e.g. non-transactional logical messages. Flush now.
277 : //
278 : // If the previous WAL record ended exactly at page boundary, pg_current_wal_insert_lsn
279 : // returns the position just after the page header on the next page. That's where the next
280 : // record will be inserted. But the page header hasn't actually been written to the WAL
281 : // yet, and if you try to flush it, you get a "request to flush past end of generated WAL"
282 : // error. Because of that, if the insert location is just after a page header, back off to
283 : // previous page boundary.
284 12 : let mut lsn = u64::from(client.pg_current_wal_insert_lsn()?);
285 12 : if lsn % WAL_SEGMENT_SIZE as u64 == XLOG_SIZE_OF_XLOG_LONG_PHD as u64 {
286 0 : lsn -= XLOG_SIZE_OF_XLOG_LONG_PHD as u64;
287 12 : } else if lsn % XLOG_BLCKSZ as u64 == XLOG_SIZE_OF_XLOG_SHORT_PHD as u64 {
288 0 : lsn -= XLOG_SIZE_OF_XLOG_SHORT_PHD as u64;
289 12 : }
290 12 : client.execute("select neon_xlogflush($1)", &[&PgLsn::from(lsn)])?;
291 12 : Ok(intermediate_lsns)
292 12 : }
293 :
294 : pub struct Simple;
295 : impl Crafter for Simple {
296 : const NAME: &'static str = "simple";
297 4 : fn craft(client: &mut impl postgres::GenericClient) -> anyhow::Result<Vec<PgLsn>> {
298 4 : craft_internal(client, |client, _| {
299 4 : client.execute("CREATE table t(x int)", &[])?;
300 4 : Ok(Vec::new())
301 4 : })
302 4 : }
303 : }
304 :
305 : pub struct LastWalRecordXlogSwitch;
306 : impl Crafter for LastWalRecordXlogSwitch {
307 : const NAME: &'static str = "last_wal_record_xlog_switch";
308 0 : fn craft(client: &mut impl postgres::GenericClient) -> anyhow::Result<Vec<PgLsn>> {
309 0 : // Do not use craft_internal because here we end up with flush_lsn exactly on
310 0 : // the segment boundary and insert_lsn after the initial page header, which is unusual.
311 0 : ensure_server_config(client)?;
312 :
313 0 : client.execute("CREATE table t(x int)", &[])?;
314 0 : let before_xlog_switch = client.pg_current_wal_insert_lsn()?;
315 : // pg_switch_wal returns end of last record of the switched segment,
316 : // i.e. end of SWITCH itself.
317 0 : let xlog_switch_record_end: PgLsn = client.query_one("SELECT pg_switch_wal()", &[])?.get(0);
318 0 : let before_xlog_switch_u64 = u64::from(before_xlog_switch);
319 0 : let next_segment = PgLsn::from(
320 0 : before_xlog_switch_u64 - (before_xlog_switch_u64 % WAL_SEGMENT_SIZE as u64)
321 0 : + WAL_SEGMENT_SIZE as u64,
322 0 : );
323 0 : ensure!(
324 0 : xlog_switch_record_end <= next_segment,
325 0 : "XLOG_SWITCH record ended after the expected segment boundary: {} > {}",
326 : xlog_switch_record_end,
327 : next_segment
328 : );
329 0 : Ok(vec![before_xlog_switch, xlog_switch_record_end])
330 0 : }
331 : }
332 :
333 : pub struct LastWalRecordXlogSwitchEndsOnPageBoundary;
334 : /// Craft xlog SWITCH record ending at page boundary.
335 : impl Crafter for LastWalRecordXlogSwitchEndsOnPageBoundary {
336 : const NAME: &'static str = "last_wal_record_xlog_switch_ends_on_page_boundary";
337 0 : fn craft(client: &mut impl postgres::GenericClient) -> anyhow::Result<Vec<PgLsn>> {
338 0 : // Do not use generate_internal because here we end up with flush_lsn exactly on
339 0 : // the segment boundary and insert_lsn after the initial page header, which is unusual.
340 0 : ensure_server_config(client)?;
341 :
342 0 : client.execute("CREATE table t(x int)", &[])?;
343 :
344 : // Add padding so the XLOG_SWITCH record ends exactly on XLOG_BLCKSZ boundary. We
345 : // will use carefully-sized logical messages to advance WAL insert location such
346 : // that there is just enough space on the page for the XLOG_SWITCH record.
347 : loop {
348 : // We start with measuring how much WAL it takes for one logical message,
349 : // considering all alignments and headers.
350 0 : let before_lsn = client.pg_current_wal_insert_lsn()?;
351 0 : client.execute(
352 0 : "SELECT pg_logical_emit_message(false, 'swch', REPEAT('a', 10))",
353 0 : &[],
354 0 : )?;
355 0 : let after_lsn = client.pg_current_wal_insert_lsn()?;
356 :
357 : // Did the record cross a page boundary? If it did, start over. Crossing a
358 : // page boundary adds to the apparent size of the record because of the page
359 : // header, which throws off the calculation.
360 0 : if u64::from(before_lsn) / XLOG_BLCKSZ as u64
361 0 : != u64::from(after_lsn) / XLOG_BLCKSZ as u64
362 : {
363 0 : continue;
364 0 : }
365 0 : // base_size is the size of a logical message without the payload
366 0 : let base_size = u64::from(after_lsn) - u64::from(before_lsn) - 10;
367 0 :
368 0 : // Is there enough space on the page for another logical message and an
369 0 : // XLOG_SWITCH? If not, start over.
370 0 : let page_remain = XLOG_BLCKSZ as u64 - u64::from(after_lsn) % XLOG_BLCKSZ as u64;
371 0 : if page_remain < base_size + XLOG_SIZE_OF_XLOG_RECORD as u64 {
372 0 : continue;
373 0 : }
374 0 :
375 0 : // We will write another logical message, such that after the logical message
376 0 : // record, there will be space for exactly one XLOG_SWITCH. How large should
377 0 : // the logical message's payload be? An XLOG_SWITCH record has no data => its
378 0 : // size is exactly XLOG_SIZE_OF_XLOG_RECORD.
379 0 : let repeats = page_remain - base_size - XLOG_SIZE_OF_XLOG_RECORD as u64;
380 0 :
381 0 : client.execute(
382 0 : "SELECT pg_logical_emit_message(false, 'swch', REPEAT('a', $1))",
383 0 : &[&(repeats as i32)],
384 0 : )?;
385 0 : info!(
386 0 : "current_wal_insert_lsn={}, XLOG_SIZE_OF_XLOG_RECORD={}",
387 0 : client.pg_current_wal_insert_lsn()?,
388 : XLOG_SIZE_OF_XLOG_RECORD
389 : );
390 :
391 : // Emit the XLOG_SWITCH
392 0 : let before_xlog_switch = client.pg_current_wal_insert_lsn()?;
393 0 : let xlog_switch_record_end: PgLsn =
394 0 : client.query_one("SELECT pg_switch_wal()", &[])?.get(0);
395 0 :
396 0 : if u64::from(xlog_switch_record_end) as usize % XLOG_BLCKSZ
397 0 : != XLOG_SIZE_OF_XLOG_SHORT_PHD
398 : {
399 0 : warn!(
400 0 : "XLOG_SWITCH message ended not on page boundary: {}, offset = {}, repeating",
401 0 : xlog_switch_record_end,
402 0 : u64::from(xlog_switch_record_end) as usize % XLOG_BLCKSZ
403 : );
404 0 : continue;
405 0 : }
406 0 : return Ok(vec![before_xlog_switch, xlog_switch_record_end]);
407 : }
408 0 : }
409 : }
410 :
411 : /// Write ~16MB logical message; it should cross WAL segment.
412 8 : fn craft_seg_size_logical_message(
413 8 : client: &mut impl postgres::GenericClient,
414 8 : transactional: bool,
415 8 : ) -> anyhow::Result<Vec<PgLsn>> {
416 8 : craft_internal(client, |client, initial_lsn| {
417 8 : ensure!(
418 8 : initial_lsn < PgLsn::from(0x0200_0000 - 1024 * 1024),
419 0 : "Initial LSN is too far in the future"
420 : );
421 :
422 8 : let message_lsn: PgLsn = client
423 8 : .query_one(
424 8 : "select pg_logical_emit_message($1, 'big-16mb-msg', \
425 8 : concat(repeat('abcd', 16 * 256 * 1024), 'end')) as message_lsn",
426 8 : &[&transactional],
427 8 : )?
428 8 : .get("message_lsn");
429 8 : ensure!(
430 8 : message_lsn > PgLsn::from(0x0200_0000 + 4 * 8192),
431 0 : "Logical message did not cross the segment boundary"
432 : );
433 8 : ensure!(
434 8 : message_lsn < PgLsn::from(0x0400_0000),
435 0 : "Logical message crossed two segments"
436 : );
437 :
438 8 : Ok(vec![message_lsn])
439 8 : })
440 8 : }
441 :
442 : pub struct WalRecordCrossingSegmentFollowedBySmallOne;
443 : impl Crafter for WalRecordCrossingSegmentFollowedBySmallOne {
444 : const NAME: &'static str = "wal_record_crossing_segment_followed_by_small_one";
445 4 : fn craft(client: &mut impl postgres::GenericClient) -> anyhow::Result<Vec<PgLsn>> {
446 4 : // Transactional message crossing WAL segment will be followed by small
447 4 : // commit record.
448 4 : craft_seg_size_logical_message(client, true)
449 4 : }
450 : }
451 :
452 : pub struct LastWalRecordCrossingSegment;
453 : impl Crafter for LastWalRecordCrossingSegment {
454 : const NAME: &'static str = "last_wal_record_crossing_segment";
455 4 : fn craft(client: &mut impl postgres::GenericClient) -> anyhow::Result<Vec<PgLsn>> {
456 4 : craft_seg_size_logical_message(client, false)
457 4 : }
458 : }
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