Commit Graph

219 Commits

Author SHA1 Message Date
Yanqin Jin
c0abc6bbc1 Use FLAGS_env for certain operations in db_bench (#5943)
Summary:
Since we already parse env_uri from command line and creates custom Env
accordingly, we should invoke the methods of such Envs instead of using
Env::Default().

Test Plan (on devserver):
```
$make db_bench db_stress
$./db_bench -benchmarks=fillseq
./db_stress
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5943

Differential Revision: D18018550

Pulled By: riversand963

fbshipit-source-id: 03b61329aaae0dfd914a0b902cc677f570f102e3
2019-10-22 11:43:21 -07:00
Zhichao Cao
526e3b9763 Enable trace_replay with multi-threads (#5934)
Summary:
In the current trace replay, all the queries are serialized and called by single threads. It may not simulate the original application query situations closely. The multi-threads replay is implemented in this PR. Users can set the number of threads to replay the trace. The queries generated according to the trace records are scheduled in the thread pool job queue.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5934

Test Plan: test with make check and real trace replay.

Differential Revision: D17998098

Pulled By: zhichao-cao

fbshipit-source-id: 87eecf6f7c17a9dc9d7ab29dd2af74f6f60212c8
2019-10-18 14:13:50 -07:00
Levi Tamasi
78b28d80b0 Support non-TTL Puts for BlobDB in db_bench (#5921)
Summary:
Currently, db_bench only supports PutWithTTL operations for BlobDB but
not regular Puts. The patch adds support for regular (non-TTL) Puts and also
changes the default for blob_db_max_ttl_range to zero, which corresponds
to no TTL.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5921

Test Plan:
make check

./db_bench -benchmarks=fillrandom -statistics -stats_interval_seconds=1
-duration=90 -num=500000 -use_blob_db=1 -blob_db_file_size=1000000
-target_file_size_base=1000000 (issues Put operations with no TTL)

./db_bench -benchmarks=fillrandom -statistics -stats_interval_seconds=1
-duration=90 -num=500000 -use_blob_db=1 -blob_db_file_size=1000000
-target_file_size_base=1000000 -blob_db_max_ttl_range=86400 (issues
PutWithTTL operations with random TTLs in the [0, blob_db_max_ttl_range)
interval, as before)

Differential Revision: D17919798

Pulled By: ltamasi

fbshipit-source-id: b946c3522b836b92b4c157ffbad24f92ba2b0a16
2019-10-14 17:49:20 -07:00
sdong
e8263dbdaa Apply formatter to recent 200+ commits. (#5830)
Summary:
Further apply formatter to more recent commits.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5830

Test Plan: Run all existing tests.

Differential Revision: D17488031

fbshipit-source-id: 137458fd94d56dd271b8b40c522b03036943a2ab
2019-09-20 12:04:26 -07:00
Lingjing You
1a928c22a0 Add insert hints for each writebatch (#5728)
Summary:
Add insert hints for each writebatch so that they can be used in concurrent write, and add write option to enable it.

Bench result (qps):

`./db_bench --benchmarks=fillseq -allow_concurrent_memtable_write=true -num=4000000 -batch-size=1 -threads=1 -db=/data3/ylj/tmp -write_buffer_size=536870912 -num_column_families=4`

master:

| batch size \ thread num | 1       | 2       | 4       | 8       |
| ----------------------- | ------- | ------- | ------- | ------- |
| 1                       | 387883  | 220790  | 308294  | 490998  |
| 10                      | 1397208 | 978911  | 1275684 | 1733395 |
| 100                     | 2045414 | 1589927 | 1798782 | 2681039 |
| 1000                    | 2228038 | 1698252 | 1839877 | 2863490 |

fillseq with writebatch hint:

| batch size \ thread num | 1       | 2       | 4       | 8       |
| ----------------------- | ------- | ------- | ------- | ------- |
| 1                       | 286005  | 223570  | 300024  | 466981  |
| 10                      | 970374  | 813308  | 1399299 | 1753588 |
| 100                     | 1962768 | 1983023 | 2676577 | 3086426 |
| 1000                    | 2195853 | 2676782 | 3231048 | 3638143 |
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5728

Differential Revision: D17297240

fbshipit-source-id: b053590a6d77871f1ef2f911a7bd013b3899b26c
2019-09-12 17:15:18 -07:00
anand76
eb9026f09b Add a db_bench benchmark to warm up the row cache
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5707

Differential Revision: D17242698

Pulled By: anand1976

fbshipit-source-id: 5d1bfda3c9e8f56176ae391cae6c91e6262016b8
2019-09-10 11:06:36 -07:00
Zhongyi Xie
2f41ecfe75 Refactor trimming logic for immutable memtables (#5022)
Summary:
MyRocks currently sets `max_write_buffer_number_to_maintain` in order to maintain enough history for transaction conflict checking. The effectiveness of this approach depends on the size of memtables. When memtables are small, it may not keep enough history; when memtables are large, this may consume too much memory.
We are proposing a new way to configure memtable list history: by limiting the memory usage of immutable memtables. The new option is `max_write_buffer_size_to_maintain` and it will take precedence over the old `max_write_buffer_number_to_maintain` if they are both set to non-zero values. The new option accounts for the total memory usage of flushed immutable memtables and mutable memtable. When the total usage exceeds the limit, RocksDB may start dropping immutable memtables (which is also called trimming history), starting from the oldest one.
The semantics of the old option actually works both as an upper bound and lower bound. History trimming will start if number of immutable memtables exceeds the limit, but it will never go below (limit-1) due to history trimming.
In order the mimic the behavior with the new option, history trimming will stop if dropping the next immutable memtable causes the total memory usage go below the size limit. For example, assuming the size limit is set to 64MB, and there are 3 immutable memtables with sizes of 20, 30, 30. Although the total memory usage is 80MB > 64MB, dropping the oldest memtable will reduce the memory usage to 60MB < 64MB, so in this case no memtable will be dropped.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5022

Differential Revision: D14394062

Pulled By: miasantreble

fbshipit-source-id: 60457a509c6af89d0993f988c9b5c2aa9e45f5c5
2019-08-23 13:55:34 -07:00
Vijay Nadimpalli
d150e01474 New API to get all merge operands for a Key (#5604)
Summary:
This is a new API added to db.h to allow for fetching all merge operands associated with a Key. The main motivation for this API is to support use cases where doing a full online merge is not necessary as it is performance sensitive. Example use-cases:
1. Update subset of columns and read subset of columns -
Imagine a SQL Table, a row is encoded as a K/V pair (as it is done in MyRocks). If there are many columns and users only updated one of them, we can use merge operator to reduce write amplification. While users only read one or two columns in the read query, this feature can avoid a full merging of the whole row, and save some CPU.
2. Updating very few attributes in a value which is a JSON-like document -
Updating one attribute can be done efficiently using merge operator, while reading back one attribute can be done more efficiently if we don't need to do a full merge.
----------------------------------------------------------------------------------------------------
API :
Status GetMergeOperands(
      const ReadOptions& options, ColumnFamilyHandle* column_family,
      const Slice& key, PinnableSlice* merge_operands,
      GetMergeOperandsOptions* get_merge_operands_options,
      int* number_of_operands)

Example usage :
int size = 100;
int number_of_operands = 0;
std::vector<PinnableSlice> values(size);
GetMergeOperandsOptions merge_operands_info;
db_->GetMergeOperands(ReadOptions(), db_->DefaultColumnFamily(), "k1", values.data(), merge_operands_info, &number_of_operands);

Description :
Returns all the merge operands corresponding to the key. If the number of merge operands in DB is greater than merge_operands_options.expected_max_number_of_operands no merge operands are returned and status is Incomplete. Merge operands returned are in the order of insertion.
merge_operands-> Points to an array of at-least merge_operands_options.expected_max_number_of_operands and the caller is responsible for allocating it. If the status returned is Incomplete then number_of_operands will contain the total number of merge operands found in DB for key.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5604

Test Plan:
Added unit test and perf test in db_bench that can be run using the command:
./db_bench -benchmarks=getmergeoperands --merge_operator=sortlist

Differential Revision: D16657366

Pulled By: vjnadimpalli

fbshipit-source-id: 0faadd752351745224ee12d4ae9ef3cb529951bf
2019-08-06 14:26:44 -07:00
Mark Rambacher
cfcf045acc The ObjectRegistry class replaces the Registrar and NewCustomObjects.… (#5293)
Summary:
The ObjectRegistry class replaces the Registrar and NewCustomObjects.  Objects are registered with the registry by Type (the class must implement the static const char *Type() method).

This change is necessary for a few reasons:
- By having a class (rather than static template instances), the class can be passed between compilation units, meaning that objects could be registered and shared from a dynamic library with an executable.
- By having a class with instances, different units could have different objects registered.  This could be useful if, for example, one Option allowed for a dynamic library and one did not.

When combined with some other PRs (being able to load shared libraries, a Configurable interface to configure objects to/from string), this code will allow objects in external shared libraries to be added to a RocksDB image at run-time, rather than requiring every new extension to be built into the main library and called explicitly by every program.

Test plan (on riversand963's  devserver)
```
$COMPILE_WITH_ASAN=1 make -j32 all && sleep 1 && make check
```
All tests pass.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5293

Differential Revision: D16363396

Pulled By: riversand963

fbshipit-source-id: fbe4acb615bfc11103eef40a0b288845791c0180
2019-07-23 17:13:05 -07:00
sdong
e4dcf5fd22 db_bench to add a new "benchmark" to print out all stats history (#5532)
Summary:
Sometimes it is helpful to fetch the whole history of stats after benchmark runs. Add such an option
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5532

Test Plan: Run the benchmark manually and observe the output is as expected.

Differential Revision: D16097764

fbshipit-source-id: 10b5b735a22a18be198b8f348be11f11f8806904
2019-07-03 20:03:28 -07:00
haoyuhuang
66464d1fde Remove multiple declarations o kMicrosInSecond.
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5526

Test Plan:
OPT=-g V=1 make J=1 unity_test -j32
make clean && make -j32

Differential Revision: D16079315

Pulled By: HaoyuHuang

fbshipit-source-id: 294ab439cf0db8dd5da44e30eabf0cbb2bb8c4f6
2019-07-01 15:15:12 -07:00
Eli Pozniansky
3e6c185381 Formatting fixes in db_bench_tool (#5525)
Summary:
Formatting fixes in db_bench_tool that were accidentally omitted
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5525

Test Plan: Unit tests

Differential Revision: D16078516

Pulled By: elipoz

fbshipit-source-id: bf8df0e3f08092a91794ebf285396d9b8a335bb9
2019-07-01 14:57:28 -07:00
Eli Pozniansky
f872009237 Fix from some C-style casting (#5524)
Summary:
Fix from some C-style casting in bloom.cc and ./tools/db_bench_tool.cc
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5524

Differential Revision: D16075626

Pulled By: elipoz

fbshipit-source-id: 352948885efb64a7ef865942c75c3c727a914207
2019-07-01 13:05:34 -07:00
Zhongyi Xie
671d15cbdd Persistent Stats: persist stats history to disk (#5046)
Summary:
This PR continues the work in https://github.com/facebook/rocksdb/pull/4748 and https://github.com/facebook/rocksdb/pull/4535 by adding a new DBOption `persist_stats_to_disk` which instructs RocksDB to persist stats history to RocksDB itself. When statistics is enabled, and  both options `stats_persist_period_sec` and `persist_stats_to_disk` are set, RocksDB will periodically write stats to a built-in column family in the following form: key -> (timestamp in microseconds)#(stats name), value -> stats value. The existing API `GetStatsHistory` will detect the current value of `persist_stats_to_disk` and either read from in-memory data structure or from the hidden column family on disk.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5046

Differential Revision: D15863138

Pulled By: miasantreble

fbshipit-source-id: bb82abdb3f2ca581aa42531734ac799f113e931b
2019-06-17 15:21:50 -07:00
haoyuhuang
d43b4cd570 Integrate block cache tracing into db_bench (#5459)
Summary:
This PR integrates the block cache tracing into db_bench. It adds three command line arguments.
-block_cache_trace_file (Block cache trace file path.) type: string default: ""
-block_cache_trace_max_trace_file_size_in_bytes (The maximum block cache
trace file size in bytes. Block cache accesses will not be logged if the
trace file size exceeds this threshold. Default is 64 GB.) type: int64
default: 68719476736
-block_cache_trace_sampling_frequency (Block cache trace sampling
frequency, termed s. It uses spatial downsampling and samples accesses to
one out of s blocks.) type: int32 default: 1
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5459

Differential Revision: D15832031

Pulled By: HaoyuHuang

fbshipit-source-id: 0ecf2f2686557251fe741a2769b21170777efa3d
2019-06-17 11:08:21 -07:00
Zhongyi Xie
d68f9f4580 simplify include directive involving inttypes (#5402)
Summary:
When using `PRIu64` type of printf specifier, current code base does the following:
```
#ifndef __STDC_FORMAT_MACROS
#define __STDC_FORMAT_MACROS
#endif
#include <inttypes.h>
```
However, this can be simplified to
```
#include <cinttypes>
```
as long as flag `-std=c++11` is used.
This should solve issues like https://github.com/facebook/rocksdb/issues/5159
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5402

Differential Revision: D15701195

Pulled By: miasantreble

fbshipit-source-id: 6dac0a05f52aadb55e9728038599d3d2e4b59d03
2019-06-06 13:56:07 -07:00
Vijay Nadimpalli
49c5a12dbe Organizing rocksdb/db directory
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5390

Differential Revision: D15579388

Pulled By: vjnadimpalli

fbshipit-source-id: 5bfc95e31554b8ff05b97b76d6534113f527f366
2019-05-31 11:57:01 -07:00
Yanqin Jin
83f7a8eed0 Fix compilation error in LITE mode (#5391)
Summary:
Add macro ROCKSDB_LITE to fix compilation.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5391

Differential Revision: D15574522

Pulled By: riversand963

fbshipit-source-id: 95aea83c5d9b2bf98a3ba0ef9167b63c9be2988b
2019-05-31 08:32:22 -07:00
Yanqin Jin
b9f5900658 Fix WAL replay by skipping old write batches (#5170)
Summary:
1. Fix a bug in WAL replay in which write batches with old sequence numbers are mistakenly inserted into memtables.
2. Add support for benchmarking secondary instance to db_bench_tool.
With changes made in this PR, we can start benchmarking secondary instance
using two processes. It is also possible to vary the frequency at which the
secondary instance tries to catch up with the primary. The info log of the
secondary can be found in a directory whose path can be specified with
'-secondary_path'.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5170

Differential Revision: D15564608

Pulled By: riversand963

fbshipit-source-id: ce97688ed3d33f69d3a0b9266ebbbbf887aa0ec8
2019-05-30 19:33:33 -07:00
Siying Dong
8843129ece Move some memory related files from util/ to memory/ (#5382)
Summary:
Move arena, allocator, and memory tools under util to a separate memory/ directory.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5382

Differential Revision: D15564655

Pulled By: siying

fbshipit-source-id: 9cd6b5d0d3d52b39606e19221fa154596e5852a5
2019-05-30 17:44:09 -07:00
Siying Dong
e9e0101ca4 Move test related files under util/ to test_util/ (#5377)
Summary:
There are too many types of files under util/. Some test related files don't belong to there or just are just loosely related. Mo
ve them to a new directory test_util/, so that util/ is cleaner.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5377

Differential Revision: D15551366

Pulled By: siying

fbshipit-source-id: 0f5c8653832354ef8caa31749c0143815d719e2c
2019-05-30 11:25:51 -07:00
Maysam Yabandeh
eab4f49a2c WritePrepared: skip_concurrency_control option (#5330)
Summary:
This enables the user to set TransactionDBOptions::skip_concurrency_control so the standard `DB::Write(const WriteOptions& opts, WriteBatch* updates)` would skip the concurrency control. This would give higher throughput to the users who know their use case doesn't need concurrency control.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5330

Differential Revision: D15525932

Pulled By: maysamyabandeh

fbshipit-source-id: 68421ac1ba34f549a4a8de9ce4c2dccf6fb4b06b
2019-05-28 16:29:45 -07:00
Zhichao Cao
a13026fb2f Added trace replay fast forward function (#5273)
Summary:
In the current db_bench trace replay, the replay process strictly follows the timestamp to issue the queries. In some cases, user does not care about the time. Therefore, fast forward is needed for users to speed up the replay process.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5273

Differential Revision: D15389232

Pulled By: zhichao-cao

fbshipit-source-id: 735d629b9d2a167b05af3e4fa0ddf9d5d0be1806
2019-05-16 20:21:18 -07:00
Maysam Yabandeh
f383641a1d Unordered Writes (#5218)
Summary:
Performing unordered writes in rocksdb when unordered_write option is set to true. When enabled the writes to memtable are done without joining any write thread. This offers much higher write throughput since the upcoming writes would not have to wait for the slowest memtable write to finish. The tradeoff is that the writes visible to a snapshot might change over time. If the application cannot tolerate that, it should implement its own mechanisms to work around that. Using TransactionDB with WRITE_PREPARED write policy is one way to achieve that. Doing so increases the max throughput by 2.2x without however compromising the snapshot guarantees.
The patch is prepared based on an original by siying
Existing unit tests are extended to include unordered_write option.

Benchmark Results:
```
TEST_TMPDIR=/dev/shm/ ./db_bench_unordered --benchmarks=fillrandom --threads=32 --num=10000000 -max_write_buffer_number=16 --max_background_jobs=64 --batch_size=8 --writes=3000000 -level0_file_num_compaction_trigger=99999 --level0_slowdown_writes_trigger=99999 --level0_stop_writes_trigger=99999 -enable_pipelined_write=false -disable_auto_compactions  --unordered_write=1
```
With WAL
- Vanilla RocksDB: 78.6 MB/s
- WRITER_PREPARED with unordered_write: 177.8 MB/s (2.2x)
- unordered_write: 368.9 MB/s (4.7x with relaxed snapshot guarantees)

Without WAL
- Vanilla RocksDB: 111.3 MB/s
- WRITER_PREPARED with unordered_write: 259.3 MB/s MB/s (2.3x)
- unordered_write: 645.6 MB/s (5.8x with relaxed snapshot guarantees)

- WRITER_PREPARED with unordered_write disable concurrency control: 185.3 MB/s MB/s (2.35x)

Limitations:
- The feature is not yet extended to `max_successive_merges` > 0. The feature is also incompatible with `enable_pipelined_write` = true as well as with `allow_concurrent_memtable_write` = false.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5218

Differential Revision: D15219029

Pulled By: maysamyabandeh

fbshipit-source-id: 38f2abc4af8780148c6128acdba2b3227bc81759
2019-05-13 17:47:21 -07:00
Yi Wu
92c60547fe db_bench: fix hang on IO error (#5300)
Summary:
db_bench will wait indefinitely if there's background error. Fix by pass `abs_time_us` to cond var.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5300

Differential Revision: D15319945

Pulled By: miasantreble

fbshipit-source-id: 0034fb7f6ec7c3303c4ccf26e54c20fbdac8ab44
2019-05-13 11:30:35 -07:00
Sagar Vemuri
3548e4220d Improve explicit user readahead performance (#5246)
Summary:
Improve the iterators performance when the user explicitly sets the readahead size via `ReadOptions.readahead_size`.

1. Stop creating new table readers when the user explicitly sets readahead size.
2. Make use of an internal buffer based on `FilePrefetchBuffer` instead of using `ReadaheadRandomAccessFileReader`, to handle the user readahead requests (for both buffered and direct io cases).
3. Add `readahead_size` to db_bench.

**Benchmarks:**
https://gist.github.com/sagar0/53693edc320a18abeaeca94ca32f5737

For 1 MB readahead, Buffered IO performance improves by 28% and Direct IO performance improves by 50%.
For 512KB readahead, Buffered IO performance improves by 30% and Direct IO performance improves by 67%.

**Test Plan:**
Updated `DBIteratorTest.ReadAhead` test to make sure that:
- no new table readers are created for iterators on setting ReadOptions.readahead_size
- At least "readahead" number of bytes are actually getting read on each iterator read.

TODO later:
- Use similar logic for compactions as well.
- This ties in nicely with #4052 and paves the way for removing ReadaheadRandomAcessFile later.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5246

Differential Revision: D15107946

Pulled By: sagar0

fbshipit-source-id: 2c1149729ca7d779e4e8b7710ba6f4e8cbfd3bea
2019-04-26 21:24:10 -07:00
Adam Retter
990b2f4cb3 Fix compilation on db_bench_tool.cc on Windows (#5227)
Summary:
I needed this change to be able to build the v6.0.1 release on Windows.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5227

Differential Revision: D15033815

Pulled By: sagar0

fbshipit-source-id: 579f3b8e694c34c0d43527eb2fa37175e37f5911
2019-04-23 11:16:51 -07:00
Zhongyi Xie
baa5302447 Avoid double-compacting data in bottom level in manual compactions (#5138)
Summary:
Depending on the config, manual compaction (leveled compaction style) does following compactions:
L0->L1
L1->L2
...
Ln-1 -> Ln
Ln -> Ln
The final Ln -> Ln compaction is partly unnecessary as it recompacts all the files that were just generated by the Ln-1 -> Ln. We should avoid recompacting such files. This rule should be applied to Lmax only.
Resolves issue https://github.com/facebook/rocksdb/issues/4995
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5138

Differential Revision: D14940106

Pulled By: miasantreble

fbshipit-source-id: 8d3cf5507a17e76f3333cfd4bac5256d005636e5
2019-04-16 23:32:20 -07:00
Yi Wu
b70967aac7 db_bench: support seek to non-exist prefix (#5163)
Summary:
Add `--seek_missing_prefix` flag to db_bench to allow benchmarking seeking to non-existing prefix. Usage example:
```
./db_bench --db=/dev/shm/db_bench --use_existing_db=false --benchmarks=fillrandom --num=100000000 --prefix_size=9 --keys_per_prefix=10
./db_bench --db=/dev/shm/db_bench --use_existing_db=true --benchmarks=seekrandom --disable_auto_compactions=true --num=100000000 --prefix_size=9 --keys_per_prefix=10 --reads=1000 --prefix_same_as_start=true --seek_missing_prefix=true
```
Also adding `--total_order_seek` and `--prefix_same_as_start` flags.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5163

Differential Revision: D14935724

Pulled By: riversand963

fbshipit-source-id: 7c41023f007febe373eb1589861f215432a9e18a
2019-04-15 10:54:58 -07:00
Yanqin Jin
3189398c00 Fix bugs detected by clang analyzer (#5185)
Summary:
as titled. False positive included, fixed anyway to make the check
pass.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5185

Differential Revision: D14909384

Pulled By: riversand963

fbshipit-source-id: dc5177e72b1929ccfd6175a60e2cd7bdb9bd80f3
2019-04-12 10:45:56 -07:00
anand76
fefd4b98c5 Introduce a new MultiGet batching implementation (#5011)
Summary:
This PR introduces a new MultiGet() API, with the underlying implementation grouping keys based on SST file and batching lookups in a file. The reason for the new API is twofold - the definition allows callers to allocate storage for status and values on stack instead of std::vector, as well as return values as PinnableSlices in order to avoid copying, and it keeps the original MultiGet() implementation intact while we experiment with batching.

Batching is useful when there is some spatial locality to the keys being queries, as well as larger batch sizes. The main benefits are due to -
1. Fewer function calls, especially to BlockBasedTableReader::MultiGet() and FullFilterBlockReader::KeysMayMatch()
2. Bloom filter cachelines can be prefetched, hiding the cache miss latency

The next step is to optimize the binary searches in the level_storage_info, index blocks and data blocks, since we could reduce the number of key comparisons if the keys are relatively close to each other. The batching optimizations also need to be extended to other formats, such as PlainTable and filter formats. This also needs to be added to db_stress.

Benchmark results from db_bench for various batch size/locality of reference combinations are given below. Locality was simulated by offsetting the keys in a batch by a stride length. Each SST file is about 8.6MB uncompressed and key/value size is 16/100 uncompressed. To focus on the cpu benefit of batching, the runs were single threaded and bound to the same cpu to eliminate interference from other system events. The results show a 10-25% improvement in micros/op from smaller to larger batch sizes (4 - 32).

Batch   Sizes

1        | 2        | 4         | 8      | 16  | 32

Random pattern (Stride length 0)
4.158 | 4.109 | 4.026 | 4.05 | 4.1 | 4.074        - Get
4.438 | 4.302 | 4.165 | 4.122 | 4.096 | 4.075 - MultiGet (no batching)
4.461 | 4.256 | 4.277 | 4.11 | 4.182 | 4.14        - MultiGet (w/ batching)

Good locality (Stride length 16)
4.048 | 3.659 | 3.248 | 2.99 | 2.84 | 2.753
4.429 | 3.728 | 3.406 | 3.053 | 2.911 | 2.781
4.452 | 3.45 | 2.833 | 2.451 | 2.233 | 2.135

Good locality (Stride length 256)
4.066 | 3.786 | 3.581 | 3.447 | 3.415 | 3.232
4.406 | 4.005 | 3.644 | 3.49 | 3.381 | 3.268
4.393 | 3.649 | 3.186 | 2.882 | 2.676 | 2.62

Medium locality (Stride length 4096)
4.012 | 3.922 | 3.768 | 3.61 | 3.582 | 3.555
4.364 | 4.057 | 3.791 | 3.65 | 3.57 | 3.465
4.479 | 3.758 | 3.316 | 3.077 | 2.959 | 2.891

dbbench command used (on a DB with 4 levels, 12 million keys)-
TEST_TMPDIR=/dev/shm numactl -C 10  ./db_bench.tmp -use_existing_db=true -benchmarks="readseq,multireadrandom" -write_buffer_size=4194304 -target_file_size_base=4194304 -max_bytes_for_level_base=16777216 -num=12000000 -reads=12000000 -duration=90 -threads=1 -compression_type=none -cache_size=4194304000 -batch_size=32 -disable_auto_compactions=true -bloom_bits=10 -cache_index_and_filter_blocks=true -pin_l0_filter_and_index_blocks_in_cache=true -multiread_batched=true -multiread_stride=4
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5011

Differential Revision: D14348703

Pulled By: anand1976

fbshipit-source-id: 774406dab3776d979c809522a67bedac6c17f84b
2019-04-11 14:28:26 -07:00
Siying Dong
2b4d5ceb47 Remove some "using std::..." from header files. (#5113)
Summary:
The code convention we are following, Google C++ Style, discourage
alias in header files, especially public headers:
https://google.github.io/styleguide/cppguide.html#Aliases
Remove some of them. Might removed some from .cc files as well to be consistent.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5113

Differential Revision: D14633030

Pulled By: siying

fbshipit-source-id: b990edc919d5de60295992284f980195e501d424
2019-03-27 10:28:21 -07:00
Shobhit Dayal
b45b1cde3e Feature for sampling and reporting compressibility (#4842)
Summary:
This is a feature to sample data-block compressibility and and report them as stats. 1 in N (tunable) blocks is sampled for compressibility using two algorithms:
1. lz4 or snappy for fast compression
2. zstd or zlib for slow but higher compression.

The stats are reported to the caller as raw-bytes and compressed-bytes. The block continues to be compressed for storage using the specified CompressionType.

The db_bench_tool how has a command line option for specifying the sampling rate. It's default value is 0 (no sampling). To test the overhead for a certain value, users can compare the performance of db_bench_tool, varying the sampling rate. It is unlikely to have a noticeable impact for high values like 20.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4842

Differential Revision: D13629011

Pulled By: shobhitdayal

fbshipit-source-id: 14ca668bcab6499b2a1734edf848eb62a4f4fafa
2019-03-18 12:15:34 -07:00
Zhichao Cao
05ebfebc17 Fixed the potential stack overflow of MixGraph in db_bench (#5051)
Summary:
In the MixGraph benchmark of db_bench, The max buffer size used for value of KV-pair might be extremely large (64MB), which might cause function stack overflow in some platforms, reduced to 1MB.

Added the finished ops printing in MixGraph benchmark.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5051

Differential Revision: D14379571

Pulled By: zhichao-cao

fbshipit-source-id: 24084fbe38f60f2902d9a40f6bc9a25e4e2c9bb9
2019-03-08 14:10:17 -08:00
Andrew Kryczka
18d2e4beb7 Run db_bench on database generated externally (#5017)
Summary:
Added an option, `-use_existing_keys`, which can be set to run
benchmarks against an arbitrary existing database. Now users can
benchmark against their actual database rather than synthetic data.

Before the run begins, it loads all the keys into memory, then uses that
set of keys rather than synthesizing new ones in `GenerateKeyFromInt`.
This is mainly intended for small-scale DBs where the memory consumption
is not a concern.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5017

Differential Revision: D14270303

Pulled By: riversand963

fbshipit-source-id: 6328df9dffb5e19170270dd00a69f4bbe424e5ed
2019-03-01 11:19:03 -08:00
Siying Dong
aef763b6d6 Make statistics's stats_level change thread-safe (#5030)
Summary:
Right now, users can change statistics.stats_level while DB is running, but TSAN may report
data race. We make stats_level_ to be atomic, and access them using accessors.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5030

Differential Revision: D14267519

Pulled By: siying

fbshipit-source-id: 37d7ebeff7a43a406230143422a16af899163f73
2019-03-01 10:42:09 -08:00
Siying Dong
5e298f865b Add two more StatsLevel (#5027)
Summary:
Statistics cost too much CPU for some use cases. Add two stats levels
so that people can choose to skip two types of expensive stats, timers and
histograms.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5027

Differential Revision: D14252765

Pulled By: siying

fbshipit-source-id: 75ecec9eaa44c06118229df4f80c366115346592
2019-02-28 10:27:59 -08:00
Zhongyi Xie
c4f5d0aa15 add GetStatsHistory to retrieve stats snapshots (#4748)
Summary:
This PR adds public `GetStatsHistory` API to retrieve stats history in the form of an std map. The key of the map is the timestamp in microseconds when the stats snapshot is taken, the value is another std map from stats name to stats value (stored in std string). Two DBOptions are introduced: `stats_persist_period_sec` (default 10 minutes) controls the intervals between two snapshots are taken; `max_stats_history_count` (default 10) controls the max number of history snapshots to keep in memory. RocksDB will stop collecting stats snapshots if `stats_persist_period_sec` is set to 0.

(This PR is the in-memory part of https://github.com/facebook/rocksdb/pull/4535)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4748

Differential Revision: D13961471

Pulled By: miasantreble

fbshipit-source-id: ac836d401ecb84ea92216bf9966f969dedf4ad04
2019-02-20 15:52:54 -08:00
Zhongyi Xie
ed995c6a69 add whole key bloom filter support in memtables (#4985)
Summary:
MyRocks calls `GetForUpdate` on `INSERT`, for unique key check, and in almost all cases GetForUpdate returns empty result. For such cases, whole key bloom filter is helpful.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4985

Differential Revision: D14118257

Pulled By: miasantreble

fbshipit-source-id: d35cb7109c62fd5ad541a26968e3a3e16d3e85ea
2019-02-19 12:15:39 -08:00
Siying Dong
4db46aa2e6 Fix LITE Build (#4989)
Summary:
LITE mode has EventListener to be an empty class. However in db_bench,
it is used. When "override" is added to the functions, the build breaks. Fix it
by keeping the listener empty in LITE mode.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4989

Differential Revision: D14108132

Pulled By: siying

fbshipit-source-id: 80121aab35b1120e502b37b782301dd700692697
2019-02-15 16:13:11 -08:00
Aubin Sanyal
3231a2e581 Deprecate ttl option from CompactionOptionsFIFO (#4965)
Summary:
We introduced ttl option in CompactionOptionsFIFO when ttl-based file
deletion (compaction) was supported only as part of FIFO Compaction. But
with the extension of ttl semantics even to Level compaction,
CompactionOptionsFIFO.ttl can now be deprecated. Instead we will start
using ColumnFamilyOptions.ttl for FIFO compaction as well.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4965

Differential Revision: D14072960

Pulled By: sagar0

fbshipit-source-id: c98cc2ae695a28136295787cd88d36a220fc219e
2019-02-15 09:51:41 -08:00
Michael Liu
ca89ac2ba9 Apply modernize-use-override (2nd iteration)
Summary:
Use C++11’s override and remove virtual where applicable.
Change are automatically generated.

Reviewed By: Orvid

Differential Revision: D14090024

fbshipit-source-id: 1e9432e87d2657e1ff0028e15370a85d1739ba2a
2019-02-14 14:41:36 -08:00
Siying Dong
cf3a671733 Remove cuckoo hash memtable (#4953)
Summary:
Cuckoo Hash is less useful than we initially expected. Remove it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4953

Differential Revision: D13979264

Pulled By: siying

fbshipit-source-id: 2a60afdaa989f045357398b43a1cc5d46f4492ed
2019-02-07 16:15:27 -08:00
Siying Dong
d9c9f3c809 db_bench: fix "micros/op" reporting (#4949)
Summary:
4985a9f73b (diff-e5276985b26a0551957144f4420a594bR511)
changes the meaning of latency reporting from running time per query, to elapse_time / #ops, without providing a reason why.
Considering that this is a counter-intuitive reporting, Reverting the change.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4949

Differential Revision: D13964684

Pulled By: siying

fbshipit-source-id: d6304d3d4b5a802daa292302623c7dbca9a680bc
2019-02-05 17:20:02 -08:00
Alexander Zinoviev
32a6dd9a41 Add a new CPU time counter to compaction report (#4889)
Summary:
Measure CPU time consumed for a compaction and report it in the stats report
Enable NowCPUNanos() to work for MacOS
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4889

Differential Revision: D13701276

Pulled By: zinoale

fbshipit-source-id: 5024e5bbccd4dd10fd90d947870237f436445055
2019-01-29 17:24:00 -08:00
zhichao-cao
e2547103fd Fix the build error caused by the dynamic array (#4918)
Summary:
In the MixGraph benchmark of db_bench #4788 , the char array is initialized with an argument from user's input, which can cause build error on some platforms. Also, the msg char array size can be potentially smaller than the printed data, which should be extended from 100 to 256.

Tested with make check.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4918

Differential Revision: D13844298

Pulled By: sagar0

fbshipit-source-id: 33c4809c5c4438f0a9f7b289d3f42e20c545bbab
2019-01-28 12:39:57 -08:00
Andrew Kryczka
e242fa4664 Add latest toolchain (gcc-8, etc.) build support for fbcode users (#4923)
Summary:
- When building with internal dependencies, specify this toolchain by setting `ROCKSDB_FBCODE_BUILD_WITH_PLATFORM007=1`
- It is not enabled by default. However, it is enabled for TSAN builds in CI since there is a known problem with TSAN in gcc-5: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71090
- I did not add support for Lua since (1) we agreed to deprecate it, and (2) we only have an internal build for v5.3 with this toolchain while that has breaking changes compared to our current version (v5.2).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4923

Differential Revision: D13827226

Pulled By: ajkr

fbshipit-source-id: 9aa3388ed3679777cfb15ef8cbcb83c07f62f947
2019-01-28 11:26:32 -08:00
Sagar Vemuri
0cead31d10 Fix Clang static analyzer warning in db_bench (#4910)
Summary:
Fixed clang static analyzer warning about division by 0.
```
ar: creating librocksdb_debug.a
tools/db_bench_tool.cc:4650:43: warning: Division by zero
      int pos = static_cast<int>(rand_num % range_);
                                 ~~~~~~~~~^~~~~~~~
1 warning generated.
make: *** [analyze] Error 1
```

This is from the new code I recently merged in ce8e88d2d7.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4910

Differential Revision: D13788037

Pulled By: sagar0

fbshipit-source-id: f48851dca85047c19fbb1a361e25ce643aa4c7ea
2019-01-23 13:33:02 -08:00
Zhongyi Xie
cbe0239270 add cast to avoid loss of precision error (#4906)
Summary:
this PR address the following error:
> tools/db_bench_tool.cc:4776:68: error: implicit conversion loses integer precision: 'int64_t' (aka 'long') to 'unsigned int' [-Werror,-Wshorten-64-to-32]
        s = db_with_cfh->db->Put(write_options_, key, gen.Generate(value_size));
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4906

Differential Revision: D13780185

Pulled By: miasantreble

fbshipit-source-id: 1c83a77d341099518c72f0f4a63e97ab9c4784b3
2019-01-22 22:44:17 -08:00
Zhichao Cao
ce8e88d2d7 Generate mixed workload with Get, Put, Seek in db_bench (#4788)
Summary:
Based on the specific workload models (key access distribution, value size distribution, and iterator scan length distribution, the QPS variation), the MixGraph benchmark generate the synthetic workload according to these distributions which can reflect the real-world workload characteristics.

After user enable the tracing function, they will get the trace file. By analyzing the trace file with the trace_analyzer tool, user can generate a set of statistic data files including. The *_accessed_key_stats.txt,  *-accessed_value_size_distribution.txt, *-iterator_length_distribution.txt, and *-qps_stats.txt are mainly used to fit the Matlab model fitting. After that, user can get the parameters of the workload distributions (the modeling details are described: [here](https://github.com/facebook/rocksdb/wiki/RocksDB-Trace%2C-Replay%2C-and-Analyzer))

The key access distribution follows the The two-term power model. The probability density function is: `f(x) = ax^{b}+c`. The corresponding parameters are key_dist_a, key_dist_b, and key_dist_c in db_bench

For the value size distribution and iterator scan length distribution, they both follow the Generalized Pareto Distribution. The probability density function is `f(x) = (1/sigma)(1+k*(x-theta)/sigma))^{-1-1/k)`. The parameters are: value_k, value_theta, value_sigma and iter_k, iter_theta, iter_sigma. For more information about the Generalized Pareto Distribution, users can find the [wiki](https://en.wikipedia.org/wiki/Generalized_Pareto_distribution) and [Matalb page](https://www.mathworks.com/help/stats/generalized-pareto-distribution.html)

As for the QPS, it follows the diurnal pattern. So Sine is a good model to fit it. `F(x) = sine_a*sin(sine_b*x + sine_c) + sine_d`. The trace_will tell you the average QPS in the print out resutls, which is sine_d. After user fit the "*-qps_stats.txt" to the Matlab model, user can get the sine_a, sine_b, and sine_c. By using the 4 parameters, user can control the QPS variation including the period, average, changes.

To use the bench mark, user can indicate the following parameters as examples:
```
-benchmarks="mixgraph" -key_dist_a=0.002312 -key_dist_b=0.3467 -value_k=0.9233 -value_sigma=226.4092 -iter_k=2.517 -iter_sigma=14.236 -mix_get_ratio=0.7 -mix_put_ratio=0.25 -mix_seek_ratio=0.05 -sine_mix_rate_interval_milliseconds=500 -sine_a=15000 -sine_b=1 -sine_d=20000
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4788

Differential Revision: D13573940

Pulled By: sagar0

fbshipit-source-id: e184c27e07b4f1bc0b436c2be36c5090c1fb0222
2019-01-22 10:44:26 -08:00