Summary:
There is a corner case when using WriteUnprepared transactions when
`WriteUnpreparedTxn::Get` returns `Status::TryAgain` instead of
propagating the result of `GetFromBatchAndDB`. The patch adds
`PermitUncheckedError` to make the `ASSERT_STATUS_CHECKED` build pass in
this case as well.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8947

Test Plan: `make check`

Reviewed By: riversand963

Differential Revision: D31125422

Pulled By: ltamasi

fbshipit-source-id: 42de51dcfa9384e032244c2b4d3f40e9a4111194

Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/8948

Reviewed By: anand1976

Differential Revision: D31127368

fbshipit-source-id: a374cb0baf88c3e15cd587a8f31e8a2d84432928

Summary:
Context/Summary:
https://github.com/facebook/rocksdb/pull/8890 added a public API `RateLimiter::GetTotalPendingRequest()` but mistakenly marked it as pure virtual, forcing RateLimiter's derived classes to implement this function and breaking backward compatibility.

This PR makes `RateLimiter::GetTotalPendingRequest()` as non-pure virtual method by providing a trivial implementation in rate_limiter.h

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8938

Test Plan: Passing existing tests

Reviewed By: pdillinger

Differential Revision: D31100661

Pulled By: hx235

fbshipit-source-id: 06eff1005156a6e5a881e393b2c5b2ad706897d8

Summary:
Several improvements to MultiRead:
1. Fix a bug in stress test which causes false positive when both MultiRead() return and individual read request have failure injected.
2. Add two more types of fault that should be handled: empty read results and checksum mismatch
3. Add a message indicating which type of fault is injected
4. Increase the failure rate

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8937

Reviewed By: anand1976

Differential Revision: D31085930

fbshipit-source-id: 3a04994a3cadebf9a64d25e1fe12b14b7a272fba

Summary:
Right now, if underlying read returns fewer bytes than asked for, RandomAccessFileReader::MultiRead() still returns those in the buffer to upper layer. This can be a surprise to upper layer.
This is unlikely to cause incorrect data. To cause incorrect data, checksum checking in upper layer should pass with short reads, whose chance is low.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8941

Test Plan: Run stress tests for a while

Reviewed By: anand1976

Differential Revision: D31085780

fbshipit-source-id: 999adf2d6c2712f1323d14bb68b678df59969973

Summary:
In FileChecksumTestHelper::VerifyEachFileChecksum(), we query the file list, and then for each file in the list verify the checksum. However, compaction can delete those files in the mean time and cause failures. To prevent it from happening, disable file deletion during the validation.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8942

Test Plan: Run exsiting test and see it doesn't fail.

Reviewed By: pdillinger

Differential Revision: D31086488

fbshipit-source-id: 554608f36d2dd3bf0a20dfc4039c68bd8533d7f8

Summary:
Updates a few remaining functions that should have been updated
from Status -> IOStatus, and adds to HISTORY for the overall change
including https://github.com/facebook/rocksdb/issues/8820.

This change is for inclusion in version 6.25.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8940

Test Plan: CI

Reviewed By: zhichao-cao

Differential Revision: D31085029

Pulled By: pdillinger

fbshipit-source-id: 91557c6a39ef1d90357d4f4dcd79af0645d87c7b

Summary:
Made SystemClock into a Customizable class, complete with CreateFromString.

Cleaned up some of the existing SystemClock implementations that were redundant (NoSleep was the same as the internal one for MockEnv).

Changed MockEnv construction to allow Clock to be passed to the Memory/MockFileSystem.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8636

Reviewed By: zhichao-cao

Differential Revision: D30483360

Pulled By: mrambacher

fbshipit-source-id: cd0e3a876c39f8c98fe13374c06e8edbd5b9f2a1

Summary:
for release

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8935

Test Plan: CI

Reviewed By: ajkr

Differential Revision: D31056726

Pulled By: pdillinger

fbshipit-source-id: 6fd022c39c19c35f10a2367df45dd2deb43df510

Summary:
In case of IO uring bugs, we need to provide a way for users to turn it off.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8931

Test Plan: Manually run db_bench with/without the option and verify the behavior

Reviewed By: pdillinger

Differential Revision: D31040252

Pulled By: anand1976

fbshipit-source-id: 56f2537d6ac8488c9e126296d8190ad9e0158f70

Summary:
Add support for fallback to local compaction, the user can
return `CompactionServiceJobStatus::kUseLocal` to instruct RocksDB to
run the compaction locally instead of waiting for the remote compaction
result.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8709

Test Plan: unittest

Reviewed By: ajkr

Differential Revision: D30560163

Pulled By: jay-zhuang

fbshipit-source-id: 65d8905a4a1bc185a68daa120997f21d3198dbe1

Summary:
In batched `MultiGet()`, RocksDB batches blob read IO and uses `RandomAccessFileReader::MultiRead()`
to read the blobs instead of issuing multiple `Read()`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8699

Test Plan:
```
make check
```

Reviewed By: ltamasi

Differential Revision: D31030861

Pulled By: riversand963

fbshipit-source-id: a0df6060cbfd54cff9515a4eee08807b1dbcb0c8

Summary:
As title. The reason is that after loading customized options, the env is not set back to the correct one. Fix it.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8929

Test Plan: Manually validate in an environment where the command failed.

Reviewed By: riversand963

Differential Revision: D31026931

fbshipit-source-id: c25dc788bf80ed5bf4b24922c442781943bcd65b

Summary:
Because even 32-bit systems can have large files

This is a "change" that I don't want intermingled with an upcoming refactoring.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8926

Test Plan: CI

Reviewed By: zhichao-cao

Differential Revision: D31020974

Pulled By: pdillinger

fbshipit-source-id: ca9eb4510697df6f1f55e37b37730b88b1809a92

Summary:
- Fixed a bug in `RateLimiterTest.GeneratePriorityIterationOrder` that the callbacks in this test were not called starting from `i = 1`. Fix by increasing `rate_bytes_per_sec` and requested bytes.
   - The bug is due to the previous `rate_bytes_per_sec` was set too small, resulting in `refill_bytes_per_period`  less than  `kMinRefillBytesPerPeriod`. Hence the actual `refill_bytes_per_period` was equal to `kMinRefillBytesPerPeriod` due to the logic [here](https://github.com/facebook/rocksdb/blob/main/util/rate_limiter.cc#L302-L303)  and it ended up being greater than the previously set requested bytes. Therefore starting from `i = 1`, `RefillBytesAndGrantRequests()` and `GeneratePriorityIterationOrder` won't be called and the test callbacks was not triggered to execute the assertion.
- Added internal flag to assert callbacks are called in `RateLimiterTest.GeneratePriorityIterationOrder` to prevent any future changes defeat the purpose of the test [as suggested](https://github.com/facebook/rocksdb/pull/8890#discussion_r704915134)
- Increased `rate_bytes_per_sec` and bytes of each request in `RateLimiterTest.GetTotalBytesThrough`, `RateLimiterTest.GetTotalRequests`, `RateLimiterTest.GetTotalPendingRequests` to trigger the "long path" of execution (i.e, the one trigger RefillBytesAndGrantRequests()) to increase test coverage
   - This increased the running time of the three tests, see test plan for time difference running locally
- Cleared up sync point effects after each test by calling `SyncPoint::GetInstance()->DisableProcessing();` and `SyncPoint::GetInstance()->ClearAllCallBacks();` in `~RateLimiterTest()` [as suggested](https://github.com/facebook/rocksdb/pull/8595/files#r697534279)
  - It's fine to call these two methods even when `EnableProcessing()` or `SetCallBack()` is not called in the test or is already cleaned up. In those cases, calling these two functions in destructor is effectively no-op.
  - This will allow cleaning up sync point effects of previous test even when the previous test failed in assertion.
- Added missing `SyncPoint::GetInstance()->DisableProcessing();` and `SyncPoint::GetInstance()->ClearCallBacks(..);` in existing tests for completeness
- Called `SyncPoint::GetInstance()->DisableProcessing();` and `SyncPoint::GetInstance()->ClearCallBacks(..);` in loop in `RateLimiterTest.GeneratePriorityIterationOrder` for completeness

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8904

Test Plan:
- Passing existing tests
- To verify the 1st change, run `RateLimiterTest.GeneratePriorityIterationOrder` with assertions of callbacks are indeed called under original `rate_bytes_per_sec` and request byte and under updated `rate_bytes_per_sec` and request byte. The former will fail the assertion while the latter succeeds.
- Here is the increased test time due to the 3rd change mentioned above in the summary. The relevant 3 tests mentioned in total increase the test time by 6s (~6000/33848 = 17.7% of the original total test time), which IMO is acceptable for better test coverage through running the "long path".
   - current (run on branch rate_limiter_ut_improve locally)

   [ RUN      ] RateLimiterTest.GetTotalBytesThrough
   [       OK ] RateLimiterTest.GetTotalBytesThrough (3000 ms)
   [ RUN      ] RateLimiterTest.GetTotalRequests
   [       OK ] RateLimiterTest.GetTotalRequests (3001 ms)
   [ RUN      ] RateLimiterTest.GetTotalPendingRequests
   [       OK ] RateLimiterTest.GetTotalPendingRequests (0 ms)
   ...
   [----------] 10 tests from RateLimiterTest (43349 ms total)

   [----------] Global test environment tear-down
   [==========] 10 tests from 1 test case ran. (43349 ms total)
   [  PASSED  ] 10 tests.

   - previous (run on branch main locally)

   [ RUN      ] RateLimiterTest.GetTotalBytesThrough
   [       OK ] RateLimiterTest.GetTotalBytesThrough (0 ms)
   [ RUN      ] RateLimiterTest.GetTotalRequests
   [       OK ] RateLimiterTest.GetTotalRequests (0 ms)
   [ RUN      ] RateLimiterTest.GetTotalPendingRequests
   [       OK ] RateLimiterTest.GetTotalPendingRequests (0 ms)
   ...
   [----------] 10 tests from RateLimiterTest (33848 ms total)

  [----------] Global test environment tear-down
  [==========] 10 tests from 1 test case ran. (33848 ms total)
  [  PASSED  ] 10 tests.

Reviewed By: ajkr

Differential Revision: D30872544

Pulled By: hx235

fbshipit-source-id: ff894f5c1a4bef70e8e407d53b00be45f776b3e4

Summary:
This keeps the implementations/API backward compatible.  Implementations of Statistics will need to override this method (and be registered with the ObjectRegistry) in order to be created via CreateFromString.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8918

Reviewed By: pdillinger

Differential Revision: D30958916

Pulled By: mrambacher

fbshipit-source-id: 75b99a84e9e11fda2a9e8eff9ee1ef69a17517b2

Summary:
1. Extend FlushJobInfo and CompactionJobInfo with information about the blob files generated by flush/compaction jobs. This PR add two structures BlobFileInfo and BlobFileGarbageInfo that contains the required information of blob files.
 2. Notify the creation and deletion of blob files through OnBlobFileCreationStarted, OnBlobFileCreated, and OnBlobFileDeleted.
 3. Test OnFile*Finish operations notifications with Blob Files.
 4. Log the blob file creation/deletion events through EventLogger in Log file.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8675

Test Plan: Add new unit tests in listener_test

Reviewed By: ltamasi

Differential Revision: D30412613

Pulled By: akankshamahajan15

fbshipit-source-id: ca51b63c6e8c8d0485a38c503572bc5a82bd5d07

Summary:
Right now, the failure injection test for MultiGet() is not sufficient. Improve it with TestFSRandomAccessFile::MultiRead() injecting failures.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8925

Test Plan: Run crash test locally for a while.

Reviewed By: anand1976

Differential Revision: D31000529

fbshipit-source-id: 439c7e02cf7440ac5af82deb609e202abdca3e1f

Summary:
Add compaction priority information in RemoteCompaction, which
can be used to schedule high priority job first.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8707

Test Plan: unittest

Reviewed By: ajkr

Differential Revision: D30548401

Pulled By: jay-zhuang

fbshipit-source-id: b30446511fb31b4583c49edd8565d496cf013a34

Summary:
One contrun name is incorrect, which mixed error reporting with another one. Fix it.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8924

Reviewed By: ltamasi

Differential Revision: D30999477

fbshipit-source-id: 46a04b2e4b48f755181aa9a47c353d91f1128469

Summary:
Test did not consider that slower deletion rate only kicks in
after a file is deleted

Fixes https://github.com/facebook/rocksdb/issues/7546

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8917

Test Plan:
no longer reproduces using

    buck test mode/dev //internal_repo_rocksdb/repo:db_sst_test -- --exact 'internal_repo_rocksdb/repo:db_sst_test - DBWALTestWithParam/DBWALTestWithParam.WALTrashCleanupOnOpen/0' --jobs 40 --stress-runs 600 --record-results

Reviewed By: siying

Differential Revision: D30949127

Pulled By: pdillinger

fbshipit-source-id: 5d0607f8f548071b07410fe8f532b4618cd225e5

Summary:
kFlushOnly currently means "always" except in the case of
remote compaction. This makes it flushes only.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8750

Test Plan: test updated

Reviewed By: akankshamahajan15

Differential Revision: D30968034

Pulled By: pdillinger

fbshipit-source-id: 5dbd24dde18852a0e937a540995fba9bfbe89037

Summary:
In order to populate the IOStatus up to the higher level, replace some of the Status to IOStatus.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8820

Test Plan: make check

Reviewed By: pdillinger

Differential Revision: D30967215

Pulled By: zhichao-cao

fbshipit-source-id: ccf9d5cfbd9d3de047c464aaa85f9fa43b474903

Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/8907

Reviewed By: zhichao-cao

Differential Revision: D30922081

Pulled By: ajkr

fbshipit-source-id: ad7a32c21d0049342fd20c9b7f555e93674c3671

Summary:
Potential bugs in the IO uring implementation can cause bad data to be returned in the completion queue. Add some checks in the PosixRandomAccessFile::MultiRead completion handling code to catch such errors and fail the entire MultiRead. Also log some diagnostic messages and stack trace.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8894

Reviewed By: siying, pdillinger

Differential Revision: D30826982

Pulled By: anand1976

fbshipit-source-id: af91815ac760e095d6cc0466cf8bd5c10167fd15

Summary:
Currently, `benchmark.sh` computes write amplification itself; the patch
changes the script to use the value calculated by RocksDB (which is
printed as part of the periodic statistics). This also has the benefit
of being correct for BlobDB as well, since it also considers the amount
of data written to blob files.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8915

Test Plan:
```
DB_DIR=/tmp/rocksdbtest/dbbench/ WAL_DIR=/tmp/rocksdbtest/dbbench/ NUM_KEYS=20000000 NUM_THREADS=32 tools/benchmark.sh overwrite --enable_blob_files=1 --enable_blob_garbage_collection=1

...

** Compaction Stats [default] **
Level    Files   Size     Score Read(GB)  Rn(GB) Rnp1(GB) Write(GB) Wnew(GB) Moved(GB) W-Amp Rd(MB/s) Wr(MB/s) Comp(sec) CompMergeCPU(sec) Comp(cnt) Avg(sec) KeyIn KeyDrop Rblob(GB) Wblob(GB)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
  L0      7/5   43.93 MB   0.5      0.3     0.0      0.3       0.5      0.3       0.0   1.0      1.3     59.9    201.35            101.88       109    1.847     22M   499K       0.0      11.2
  L4      4/4   244.03 MB   0.0     11.4     0.3      1.6       1.6      0.0       0.0   1.1     50.6     49.3    231.10            288.84         7   33.014    156M    26M       9.5       9.5
  L5     36/0    3.28 GB   0.0      0.0     0.0      0.0       0.0      0.0       0.0   0.0      0.0      0.0      0.00              0.00         0    0.000       0      0       0.0       0.0
 Sum     47/9    3.56 GB   0.0     11.7     0.3      1.8       2.2      0.3       0.0   2.0     27.6     54.3    432.45            390.72       116    3.728    179M    26M       9.5      20.8
 Int      0/0    0.00 KB   0.0      3.5     0.1      0.5       0.6      0.1       0.0   2.2     31.2     55.6    115.01            109.53        29    3.966     51M  7353K       2.9       5.6

...

Completed overwrite (ID: ) in 289 seconds
ops/sec	mb/sec	Size-GB	L0_GB	Sum_GB	W-Amp	W-MB/s	usec/op	p50	p75	p99	p99.9	p99.99	Uptime	Stall-time	Stall%	Test	Date	Version	Job-ID
111784	44.8	0.0	0.5	2.2	2.0	9.2	285.9	215.3	264.4	1232	13299	23310	243	00:00:0.000	0.0	overwrite.t32.s0	2021-09-14T11:58:26.000-07:00	6.24
```

Reviewed By: zhichao-cao

Differential Revision: D30940352

Pulled By: ltamasi

fbshipit-source-id: ae7f5cd5440c8529788dda043266121fc2be0853

Summary:
ArenaWrappedDBIter::db_iter_ should never be nullptr. However, when debugging a segfault, it's hard to distinguish it is not initialized (not possible) and other corruption. Add this nullptr to help distinguish the case.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8889

Test Plan: Run existing unit tests.

Reviewed By: pdillinger

Differential Revision: D30814756

fbshipit-source-id: 4b1f36896a33dc203d4f1f424ded9554927d61ba

Summary:
After https://github.com/facebook/rocksdb/issues/8725, keys added to `WriteBatch` may be timestamp-suffixed, while `WriteBatch` has no awareness of the timestamp size. Therefore, `WriteBatch` can no longer calculate timestamp checksum separately from the rest of the key's checksum in all cases.

This PR changes the definition of key in KV checksum to include the timestamp suffix. That way we do not need to worry about where the timestamp begins within the key. I believe the only practical effect of this change is now `AssignTimestamp()` requires recomputing the whole key checksum (`UpdateK()`) rather than just the timestamp portion (`UpdateT()`).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8914

Test Plan:
run stress command that used to fail

```
$ ./db_stress --batch_protection_bytes_per_key=8 -clear_column_family_one_in=0 -test_batches_snapshots=1
```

Reviewed By: riversand963

Differential Revision: D30925715

Pulled By: ajkr

fbshipit-source-id: c143f7ccb46c0efb390ad57ef415c250d754deff

Summary:
* Started on some proper usage text to document the options
* Added a `JOB_ID` parameter, so that we can trace jobs and relate them to other assets
* Now generates a correct TSV file of the summary
* Summary has new additional fields:
    * RocksDB Version
    * Date
    * Job ID
* db_bench log files now also include the Job ID

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8730

Reviewed By: mrambacher

Differential Revision: D30747344

Pulled By: jay-zhuang

fbshipit-source-id: 87eb78d20959b6d95804aebf129606fa9c71f407

Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/8911

Reviewed By: zhichao-cao

Differential Revision: D30908552

Pulled By: cheng-chang

fbshipit-source-id: df2ab50d94ed46bfb54f0dd520f8a5cdbfa49fd1

Summary:
Fix WAL log data corruption when using DBOptions.manual_wal_flush(true) and WriteOptions.sync(true) together (https://github.com/facebook/rocksdb/issues/8723)

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8746

Reviewed By: ajkr

Differential Revision: D30758468

Pulled By: riversand963

fbshipit-source-id: 07c20899d5f2447dc77861b4845efc68a59aa4e8

Summary:
These tests would frequently fail to find SST files due to race
condition in running ldb (read-only) on an open DB which might do automatic
compaction. But only sometimes would that failure translate into test
failure because the implementation of ldb file_checksum_dump would
swallow many errors. Now,

* DB closed while running ldb to avoid unnecessary race condition
* Detect and report/propagate more failures in `ldb file_checksum_dump`
* Use --hex so that random binary data is not printed to console

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8898

Test Plan: ./ldb_cmd_test --gtest_filter=*Checksum* --gtest_repeat=100

Reviewed By: zhichao-cao

Differential Revision: D30848738

Pulled By: pdillinger

fbshipit-source-id: 20290b517eeceba99bb538bb5a17088f7e878405

Summary:
Facebook infrastructure doesn't like continuously skipping
tests, so fixing this permanently disabled parameterization to BYPASS
instead of SKIP. (Internal ref: T100525285)

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8910

Test Plan: manual

Reviewed By: anand1976

Differential Revision: D30905169

Pulled By: pdillinger

fbshipit-source-id: e23d63d2aa800e54676269fad3a093cd3f9f222d

Summary:
The patch adjusts the definition of BlobDB's DB properties a bit by
switching to `GetBlobFileSize` from `GetTotalBlobBytes`. The
difference is that the value returned by `GetBlobFileSize` includes
the blob file header and footer as well, and thus matches the on-disk
size of blob files. In addition, the patch removes the `Version` number
from the `blob_stats` property, and updates/extends the unit tests a little.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8902

Test Plan: `make check`

Reviewed By: riversand963

Differential Revision: D30859542

Pulled By: ltamasi

fbshipit-source-id: e3426d2d567bd1bd8c8636abdafaafa0743c854c

Summary:
Hi. Hope this helps :)

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8906

Reviewed By: jay-zhuang

Differential Revision: D30890111

Pulled By: zhichao-cao

fbshipit-source-id: 45a4119158dc38cb4220b1d6d571bb1ca9902ffc

Summary:
This allows the wrapper classes to own the wrapped object and eliminates confusion as to ownership.  Previously, many classes implemented their own ownership solutions.  Fixes https://github.com/facebook/rocksdb/issues/8606

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8618

Reviewed By: pdillinger

Differential Revision: D30136064

Pulled By: mrambacher

fbshipit-source-id: d0bf471df8818dbb1770a86335fe98f761cca193

Summary:
In the past, we unnecessarily requires all keys in the same write batch
to be from column families whose timestamps' formats are the same for
simplicity. Specifically, we cannot use the same write batch to write to
two column families, one of which enables timestamp while the other
disables it.

The limitation is due to the member `timestamp_size_` that used to exist
in each `WriteBatch` object. We pass a timestamp_size to the constructor
of `WriteBatch`. Therefore, users can simply use the old
`WriteBatch::Put()`, `WriteBatch::Delete()`, etc APIs for write, while
the internal implementation of `WriteBatch` will take care of memory
allocation for timestamps.

The above is not necessary.
One the one hand, users can set up a memory buffer to store user key and
then contiguously append the timestamp to the user key. Then the user
can pass this buffer to the `WriteBatch::Put(Slice&)` API.
On the other hand, users can set up a SliceParts object which is an
array of Slices and let the last Slice to point to the memory buffer
storing timestamp. Then the user can pass the SliceParts object to the
`WriteBatch::Put(SliceParts&)` API.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8725

Test Plan: make check

Reviewed By: ltamasi

Differential Revision: D30654499

Pulled By: riversand963

fbshipit-source-id: 9d848c77ad3c9dd629aa5fc4e2bc16fb0687b4a2

Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/8905

Reviewed By: zhichao-cao

Differential Revision: D30873416

Pulled By: ltamasi

fbshipit-source-id: 6e55ec14a7fd2e562aa24cd0274e2436369923f5

Summary:
It's always annoying to find a header does not include its own
dependencies and only works when included after other includes. This
change adds `make check-headers` which validates that each header can
be included at the top of a file. Some headers are excluded e.g. because
of platform or external dependencies.

rocksdb_namespace.h had to be re-worked slightly to enable checking for
failure to include it. (ROCKSDB_NAMESPACE is a valid namespace name.)

Fixes mostly involve adding and cleaning up #includes, but for
FileTraceWriter, a constructor was out-of-lined to make a forward
declaration sufficient.

This check is not currently run with `make check` but is added to
CircleCI build-linux-unity since that one is already relatively fast.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8893

Test Plan: existing tests and resolving issues detected by new check

Reviewed By: mrambacher

Differential Revision: D30823300

Pulled By: pdillinger

fbshipit-source-id: 9fff223944994c83c105e2e6496d24845dc8e572

Summary:
Make the Statistics object into a Customizable object.  Statistics can now be stored and created to/from the Options file.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8637

Reviewed By: zhichao-cao

Differential Revision: D30530550

Pulled By: mrambacher

fbshipit-source-id: 5fc7d01d8431f37b2c205bbbd8342c9f697023bd