Commit Graph

8 Commits

Author SHA1 Message Date
Hui Xiao a5d773e077 Add rate-limiting support to batched MultiGet() (#10159)
Summary:
**Context/Summary:**
https://github.com/facebook/rocksdb/pull/9424 added rate-limiting support for user reads, which does not include batched `MultiGet()`s that call `RandomAccessFileReader::MultiRead()`. The reason is that it's harder (compared with RandomAccessFileReader::Read()) to implement the ideal rate-limiting where we first call `RateLimiter::RequestToken()` for allowed bytes to multi-read and then consume those bytes by satisfying as many requests in `MultiRead()` as possible. For example, it can be tricky to decide whether we want partially fulfilled requests within one `MultiRead()` or not.

However, due to a recent urgent user request, we decide to pursue an elementary (but a conditionally ineffective) solution where we accumulate enough rate limiter requests toward the total bytes needed by one `MultiRead()` before doing that `MultiRead()`. This is not ideal when the total bytes are huge as we will actually consume a huge bandwidth from rate-limiter causing a burst on disk. This is not what we ultimately want with rate limiter. Therefore a follow-up work is noted through TODO comments.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10159

Test Plan:
- Modified existing unit test `DBRateLimiterOnReadTest/DBRateLimiterOnReadTest.NewMultiGet`
- Traced the underlying system calls `io_uring_enter` and verified they are 10 seconds apart from each other correctly under the setting of  `strace -ftt -e trace=io_uring_enter ./db_bench -benchmarks=multireadrandom -db=/dev/shm/testdb2 -readonly -num=50 -threads=1 -multiread_batched=1 -batch_size=100 -duration=10 -rate_limiter_bytes_per_sec=200 -rate_limiter_refill_period_us=1000000 -rate_limit_bg_reads=1 -disable_auto_compactions=1 -rate_limit_user_ops=1` where each `MultiRead()` read about 2000 bytes (inspected by debugger) and the rate limiter grants 200 bytes per seconds.
- Stress test:
   - Verified `./db_stress (-test_cf_consistency=1/test_batches_snapshots=1) -use_multiget=1 -cache_size=1048576 -rate_limiter_bytes_per_sec=10241024 -rate_limit_bg_reads=1 -rate_limit_user_ops=1` work

Reviewed By: ajkr, anand1976

Differential Revision: D37135172

Pulled By: hx235

fbshipit-source-id: 73b8e8f14761e5d4b77235dfe5d41f4eea968bcd
2022-06-17 16:40:47 -07:00
Yanqin Jin 514f0b0937 Fail DB::Open() if logger cannot be created (#9984)
Summary:
For regular db instance and secondary instance, we return error and refuse to open DB if Logger creation fails.

Our current code allows it, but it is really difficult to debug because
there will be no LOG files. The same for OPTIONS file, which will be explored in another PR.

Furthermore, Arena::AllocateAligned(size_t bytes, size_t huge_page_size, Logger* logger) has an
assertion as the following:

```cpp
#ifdef MAP_HUGETLB
if (huge_page_size > 0 && bytes > 0) {
  assert(logger != nullptr);
}
#endif
```

It can be removed.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9984

Test Plan: make check

Reviewed By: jay-zhuang

Differential Revision: D36347754

Pulled By: riversand963

fbshipit-source-id: 529798c0511d2eaa2f0fd40cf7e61c4cbc6bc57e
2022-05-27 07:23:31 -07:00
tagliavini 6c50082654 Remove code that only compiles for Visual Studio versions older than 2015 (#10065)
Summary:
There are currently some preprocessor checks that assume support for Visual Studio versions older than 2015 (i.e., 0 < _MSC_VER < 1900), although we don't support them any more.

We removed all code that only compiles on those older versions, except third-party/ files.

The ROCKSDB_NOEXCEPT symbol is now obsolete, since it now always gets replaced by noexcept. We removed it.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10065

Reviewed By: pdillinger

Differential Revision: D36721901

Pulled By: guidotag

fbshipit-source-id: a2892d365ef53cce44a0a7d90dd6b72ee9b5e5f2
2022-05-26 16:55:08 -07:00
Changyu Bi 8515bd50c9 Support read rate-limiting in SequentialFileReader (#9973)
Summary:
Added rate limiter and read rate-limiting support to SequentialFileReader. I've updated call sites to SequentialFileReader::Read with appropriate IO priority (or left a TODO and specified IO_TOTAL for now).

The PR is separated into four commits: the first one added the rate-limiting support, but with some fixes in the unit test since the number of request bytes from rate limiter in SequentialFileReader are not accurate (there is overcharge at EOF). The second commit fixed this by allowing SequentialFileReader to check file size and determine how many bytes are left in the file to read. The third commit added benchmark related code. The fourth commit moved the logic of using file size to avoid overcharging the rate limiter into backup engine (the main user of SequentialFileReader).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9973

Test Plan:
- `make check`, backup_engine_test covers usage of SequentialFileReader with rate limiter.
- Run db_bench to check if rate limiting is throttling as expected: Verified that reads and writes are together throttled at 2MB/s, and at 0.2MB chunks that are 100ms apart.
  - Set up: `./db_bench --benchmarks=fillrandom -db=/dev/shm/test_rocksdb`
  - Benchmark:
```
strace -ttfe read,write ./db_bench --benchmarks=backup -db=/dev/shm/test_rocksdb --backup_rate_limit=2097152 --use_existing_db
strace -ttfe read,write ./db_bench --benchmarks=restore -db=/dev/shm/test_rocksdb --restore_rate_limit=2097152 --use_existing_db
```
- db bench on backup and restore to ensure no performance regression.
  - backup (avg over 50 runs): pre-change: 1.90443e+06 micros/op; post-change: 1.8993e+06 micros/op (improve by 0.2%)
  - restore (avg over 50 runs): pre-change: 1.79105e+06 micros/op; post-change: 1.78192e+06 micros/op (improve by 0.5%)

```
# Set up
./db_bench --benchmarks=fillrandom -db=/tmp/test_rocksdb -num=10000000

# benchmark
TEST_TMPDIR=/tmp/test_rocksdb
NUM_RUN=50
for ((j=0;j<$NUM_RUN;j++))
do
   ./db_bench -db=$TEST_TMPDIR -num=10000000 -benchmarks=backup -use_existing_db | egrep 'backup'
  # Restore
  #./db_bench -db=$TEST_TMPDIR -num=10000000 -benchmarks=restore -use_existing_db
done > rate_limit.txt && awk -v NUM_RUN=$NUM_RUN '{sum+=$3;sum_sqrt+=$3^2}END{print sum/NUM_RUN, sqrt(sum_sqrt/NUM_RUN-(sum/NUM_RUN)^2)}' rate_limit.txt >> rate_limit_2.txt
```

Reviewed By: hx235

Differential Revision: D36327418

Pulled By: cbi42

fbshipit-source-id: e75d4307cff815945482df5ba630c1e88d064691
2022-05-24 10:28:57 -07:00
Hui Xiao e66e6d2faa Use SpecialEnv to speed up some slow BackupEngineRateLimitingTestWithParam (#9974)
Summary:
**Context:**
`BackupEngineRateLimitingTestWithParam.RateLimiting` and `BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup` involve creating backup and restoring of a big database with rate-limiting. Using the normal env with a normal clock requires real elapse of time (13702 - 19848 ms/per test). As suggested in https://github.com/facebook/rocksdb/pull/8722#discussion_r703698603, this PR is to speed it up with SpecialEnv (`time_elapse_only_sleep=true`) where its clock accepts fake elapse of time during rate-limiting (100 - 600 ms/per test)

**Summary:**
- Added TEST_ function to set clock of the default rate limiters in backup engine
- Shrunk testdb by 10 times while keeping it big enough for testing
- Renamed some test variables and reorganized some if-else branch for clarity without changing the test

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9974

Test Plan:
- Run tests pre/post PR the same time to verify the tests are sped up by 90 - 95%
`BackupEngineRateLimitingTestWithParam.RateLimiting`
Pre:
```
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/0
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/0 (11123 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/1
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/1 (9441 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/2
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/2 (11096 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/3
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/3 (9339 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/4
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/4 (11121 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/5
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/5 (9413 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/6
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/6 (11185 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/7
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/7 (9511 ms)
[----------] 8 tests from RateLimiting/BackupEngineRateLimitingTestWithParam (82230 ms total)
```
Post:
```
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/0
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/0 (395 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/1
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/1 (564 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/2
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/2 (358 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/3
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/3 (567 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/4
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/4 (173 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/5
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/5 (176 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/6
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/6 (191 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/7
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/7 (177 ms)
[----------] 8 tests from RateLimiting/BackupEngineRateLimitingTestWithParam (2601 ms total)
```
`BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup`
Pre:
```
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/0
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/0 (7275 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/1
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/1 (3961 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/2
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/2 (7117 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/3
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/3 (3921 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/4
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/4 (19862 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/5
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/5 (10231 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/6
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/6 (19848 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/7
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/7 (10372 ms)
[----------] 8 tests from RateLimiting/BackupEngineRateLimitingTestWithParam (82587 ms total)
```
Post:
```
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/0
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/0 (157 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/1
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/1 (152 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/2
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/2 (160 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/3
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/3 (158 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/4
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/4 (155 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/5
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/5 (151 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/6
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/6 (146 ms)
[ RUN      ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/7
[       OK ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimitingVerifyBackup/7 (153 ms)
[----------] 8 tests from RateLimiting/BackupEngineRateLimitingTestWithParam (1232 ms total)
```

Reviewed By: pdillinger

Differential Revision: D36336345

Pulled By: hx235

fbshipit-source-id: 724c6ba745f95f56d4440a6d2f1e4512a2987589
2022-05-16 10:54:02 -07:00
sdong 736a7b5433 Remove own ToString() (#9955)
Summary:
ToString() is created as some platform doesn't support std::to_string(). However, we've already used std::to_string() by mistake for 16 months (in db/db_info_dumper.cc). This commit just remove ToString().

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9955

Test Plan: Watch CI tests

Reviewed By: riversand963

Differential Revision: D36176799

fbshipit-source-id: bdb6dcd0e3a3ab96a1ac810f5d0188f684064471
2022-05-06 13:03:58 -07:00
sdong 49628c9a83 Use std::numeric_limits<> (#9954)
Summary:
Right now we still don't fully use std::numeric_limits but use a macro, mainly for supporting VS 2013. Right now we only support VS 2017 and up so it is not a problem. The code comment claims that MinGW still needs it. We don't have a CI running MinGW so it's hard to validate. since we now require C++17, it's hard to imagine MinGW would still build RocksDB but doesn't support std::numeric_limits<>.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9954

Test Plan: See CI Runs.

Reviewed By: riversand963

Differential Revision: D36173954

fbshipit-source-id: a35a73af17cdcae20e258cdef57fcf29a50b49e0
2022-05-05 13:08:21 -07:00
Peter Dillinger 6534c6dea4 Fix remaining uses of "backupable" (#9792)
Summary:
Various renaming and fixes to get rid of remaining uses of
"backupable" which is terminology leftover from the original, flawed
design of BackupableDB. Now any DB can be backed up, using BackupEngine.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9792

Test Plan: CI

Reviewed By: ajkr

Differential Revision: D35334386

Pulled By: pdillinger

fbshipit-source-id: 2108a42b4575c8cccdfd791c549aae93ec2f3329
2022-04-05 09:52:33 -07:00