Commit Graph

21 Commits

Author SHA1 Message Date
Yanqin Jin
dd203ed604 Disallow a combination of options (#9348)
Summary:
Disallow `immutable_db_opts.use_direct_io_for_flush_and_compaction == true` and
`mutable_db_opts.writable_file_max_buffer_size == 0`, since it causes `WritableFileWriter::Append()`
to loop forever and does not make much sense in direct IO.

This combination of options itself does not make much sense: asking RocksDB to do direct IO but not allowing
RocksDB to allocate a buffer. We should detect this false combination and warn user early, no matter whether
the application is running on a platform that supports direct IO or not. In the case of platform **not** supporting
direct IO, it's ok if the user learns about this and then finds that direct IO is not supported.

One tricky thing: the constructor of `WritableFileWriter` is being used in our unit tests, and it's impossible
to return status code from constructor. Since we do not throw, I put an assertion for now. Fortunately,
the constructor is not exposed to external applications.

Closing https://github.com/facebook/rocksdb/issues/7109

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9348

Test Plan: make check

Reviewed By: ajkr

Differential Revision: D33371924

Pulled By: riversand963

fbshipit-source-id: 2a3701ab541cee23bffda8a36cdf37b2d235edfa
2022-01-27 19:30:24 -08:00
Yanqin Jin
08721293ea Fix a bug causing duplicate trailing entries in WritableFile (buffered IO) (#9236)
Summary:
`db_stress` is a user of `FaultInjectionTestFS`. After injecting a write error, `db_stress` probabilistically determins
data drop (https://github.com/facebook/rocksdb/blob/6.27.fb/db_stress_tool/db_stress_test_base.cc#L2615:L2619).

In some of our recent runs of `db_stress`, we found duplicate trailing entries corresponding to file trivial move in
the MANIFEST, causing the recovery to fail, because the file move operation is not idempotent: you cannot delete a
file from a given level twice.

Investigation suggests that data buffering in both `WritableFileWriter` and `FaultInjectionTestFS` may be the root cause.

WritableFileWriter buffers data to write in a memory buffer, `WritableFileWriter::buf_`. After each
`WriteBuffered()`/`WriteBufferedWithChecksum()` succeeds, the `buf_` is cleared.

If the underlying file `WritableFileWriter::writable_file_` is opened in buffered IO mode, then `FaultInjectionTestFS`
buffers data written for each file until next file sync. After an injected error, user of `FaultInjectionFS` can
choose to drop some or none of previously buffered data. If `db_stress` does not drop any unsynced data, then
such data will still exist in the `FaultInjectionTestFS`'s buffer.

Existing implementation of `WritableileWriter::WriteBuffered()` does not clear `buf_` if there is an error. This may lead
to the data being buffered two copies: one in `WritableFileWriter`, and another in `FaultInjectionTestFS`.
We also know that the `WritableFileWriter` of MANIFEST file will close upon an error.  During `Close()`, it will flush the
content in `buf_`. If no write error is injected to `FaultInjectionTestFS` this time, then we end up with two copies of the
data appended to the file.

To fix, we clear the `WritableFileWriter::buf_` upon failure as well. We focus this PR on files opened in non-direct mode.

This PR includes a unit test to reproduce a case when write error injection
to `WritableFile` can cause duplicate trailing entries.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9236

Test Plan: make check

Reviewed By: zhichao-cao

Differential Revision: D33033984

Pulled By: riversand963

fbshipit-source-id: ebfa5a0db8cbf1ed73100528b34fcba543c5db31
2021-12-13 09:00:36 -08:00
Akanksha Mahajan
4a7c1dc375 Add listener API that notifies on IOError (#9177)
Summary:
Add a new API in listener.h that notifies about IOErrors on
Read/Write/Append/Flush etc. The API reports about IOStatus, filename, Operation
name, offset and length.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9177

Test Plan: Added new unit tests

Reviewed By: anand1976

Differential Revision: D32470627

Pulled By: akankshamahajan15

fbshipit-source-id: 189a717033590ae227b3beae8b1e7e185e4cdc12
2021-11-18 17:11:19 -08:00
Zhichao Cao
699f45049d Introduce a mechanism to dump out blocks from block cache and re-insert to secondary cache (#8912)
Summary:
Background: Cache warming up will cause potential read performance degradation due to reading blocks from storage to the block cache. Since in production, the workload and access pattern to a certain DB is stable, it is a potential solution to dump out the blocks belonging to a certain DB to persist storage (e.g., to a file) and bulk-load the blocks to Secondary cache before the DB is relaunched. For example, when migrating a DB form host A to host B, it will take a short period of time, the access pattern to blocks in the block cache will not change much. It is efficient to dump out the blocks of certain DB, migrate to the destination host and insert them to the Secondary cache before we relaunch the DB.

Design: we introduce the interface of CacheDumpWriter and CacheDumpRead for user to store the blocks dumped out from block cache. RocksDB will encode all the information and send the string to the writer. User can implement their own writer it they want. CacheDumper and CacheLoad are introduced to save the blocks and load the blocks respectively.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8912

Test Plan: add new tests to lru_cache_test and pass make check.

Reviewed By: pdillinger

Differential Revision: D31452871

Pulled By: zhichao-cao

fbshipit-source-id: 11ab4f5d03e383f476947116361d54188d36ec48
2021-10-07 11:42:31 -07:00
Zhichao Cao
a904c62d28 Using existing crc32c checksum in checksum handoff for Manifest and WAL (#8412)
Summary:
In PR https://github.com/facebook/rocksdb/issues/7523 , checksum handoff is introduced in RocksDB for WAL, Manifest, and SST files. When user enable checksum handoff for a certain type of file, before the data is written to the lower layer storage system, we calculate the checksum (crc32c) of each piece of data and pass the checksum down with the data, such that data verification can be down by the lower layer storage system if it has the capability. However, it cannot cover the whole lifetime of the data in the memory and also it potentially introduces extra checksum calculation overhead.

In this PR, we introduce a new interface in WritableFileWriter::Append, which allows the caller be able to pass the data and the checksum (crc32c) together. In this way, WritableFileWriter can directly use the pass-in checksum (crc32c) to generate the checksum of data being passed down to the storage system. It saves the calculation overhead and achieves higher protection coverage. When a new checksum is added with the data, we use Crc32cCombine https://github.com/facebook/rocksdb/issues/8305 to combine the existing checksum and the new checksum. To avoid the segmenting of data by rate-limiter before it is stored, rate-limiter is called enough times to accumulate enough credits for a certain write. This design only support Manifest and WAL which use log_writer in the current stage.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8412

Test Plan: make check, add new testing cases.

Reviewed By: anand1976

Differential Revision: D29151545

Pulled By: zhichao-cao

fbshipit-source-id: 75e2278c5126cfd58393c67b1efd18dcc7a30772
2021-06-25 00:47:17 -07:00
sdong
e19908cba6 Refactor kill point (#8241)
Summary:
Refactor kill point to one single class, rather than several extern variables. The intention was to drop unflushed data before killing to simulate some job, and I tried to a pointer to fault ingestion fs to the killing class, but it ended up with harder than I thought. Perhaps we'll need to do this in another way. But I thought the refactoring itself is good so I send it out.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8241

Test Plan: make release and run crash test for a while.

Reviewed By: anand1976

Differential Revision: D28078486

fbshipit-source-id: f9182c1455f52e6851c13f88a21bade63bcec45f
2021-05-05 15:50:29 -07:00
Zhichao Cao
d1c510baec Handoff checksum Implementation (#7523)
Summary:
in PR https://github.com/facebook/rocksdb/issues/7419 , we introduce the new Append and PositionedAppend APIs to WritableFile at File System, which enable RocksDB to pass the data verification information (e.g., checksum of the data) to the lower layer. In this PR, we use the new API in WritableFileWriter, such that the file created via WritableFileWrite can pass the checksum to the storage layer. To control which types file should apply the checksum handoff, we add checksum_handoff_file_types to DBOptions. User can use this option to control which file types (Currently supported file tyes: kLogFile, kTableFile, kDescriptorFile.) should use the new Append and PositionedAppend APIs to handoff the verification information.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7523

Test Plan: add new unit test, pass make check/ make asan_check

Reviewed By: pdillinger

Differential Revision: D24313271

Pulled By: zhichao-cao

fbshipit-source-id: aafd69091ae85c3318e3e17cbb96fe7338da11d0
2021-02-10 22:20:32 -08:00
mrambacher
4a09d632c4 Remove Legacy and Custom FileWrapper classes from header files (#7851)
Summary:
Removed the uses of the Legacy FileWrapper classes from the source code.  The wrappers were creating an additional layer of indirection/wrapping, as the Env already has a FileSystem.

Moved the Custom FileWrapper classes into the CustomEnv, as these classes are really for the private use the the CustomEnv class.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7851

Reviewed By: anand1976

Differential Revision: D26114816

Pulled By: mrambacher

fbshipit-source-id: db32840e58d969d3a0fa6c25aaf13d6dcdc74150
2021-01-28 22:10:32 -08:00
mrambacher
12f1137355 Add a SystemClock class to capture the time functions of an Env (#7858)
Summary:
Introduces and uses a SystemClock class to RocksDB.  This class contains the time-related functions of an Env and these functions can be redirected from the Env to the SystemClock.

Many of the places that used an Env (Timer, PerfStepTimer, RepeatableThread, RateLimiter, WriteController) for time-related functions have been changed to use SystemClock instead.  There are likely more places that can be changed, but this is a start to show what can/should be done.  Over time it would be nice to migrate most (if not all) of the uses of the time functions from the Env to the SystemClock.

There are several Env classes that implement these functions.  Most of these have not been converted yet to SystemClock implementations; that will come in a subsequent PR.  It would be good to unify many of the Mock Timer implementations, so that they behave similarly and be tested similarly (some override Sleep, some use a MockSleep, etc).

Additionally, this change will allow new methods to be introduced to the SystemClock (like https://github.com/facebook/rocksdb/issues/7101 WaitFor) in a consistent manner across a smaller number of classes.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7858

Reviewed By: pdillinger

Differential Revision: D26006406

Pulled By: mrambacher

fbshipit-source-id: ed10a8abbdab7ff2e23d69d85bd25b3e7e899e90
2021-01-25 22:09:11 -08:00
Akanksha Mahajan
b175eceb09 Store FSWritableFilePtr object in WritableFileWriter (#7193)
Summary:
Replace FSWritableFile pointer with FSWritableFilePtr
    object in WritableFileWriter.
    This new object wraps FSWritableFile pointer.

    Objective: If tracing is enabled, FSWritableFile Ptr returns
    FSWritableFileTracingWrapper pointer that includes all necessary
    information in IORecord and calls underlying FileSystem and invokes
    IOTracer to dump that record in a binary file. If tracing is disabled
    then, underlying FileSystem pointer is returned directly.
    FSWritableFilePtr wrapper class is added to bypass the
    FSWritableFileWrapper when
    tracing is disabled.

    Test Plan: make check -j64

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7193

Reviewed By: anand1976

Differential Revision: D23355915

Pulled By: akankshamahajan15

fbshipit-source-id: e62a27a13c1fd77e36a6dbafc7006d969bed25cf
2020-09-08 10:56:08 -07:00
Haosen Wen
dbc51adbac Use steady_clock instead of system_clock in FileOperationInfo::TimePoint (#7153)
Summary:
Issue https://github.com/facebook/rocksdb/issues/7133 reported that using `system_clock` in `FileOperationInfo::TimePoint` causes the duration of file flush operation (which can be a noop on MacOS in some scenarios) appears to be 0 and fail an assertion in listener_test. Using `steady_clock` supposedly fixed the problem.
`steady_clock` actually fits better into the use cases of `FileOperationInfo::TimePoint` as all usages care about durations but not wall clock time.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7153

Test Plan: make check.

Reviewed By: riversand963

Differential Revision: D22654136

Pulled By: roghnin

fbshipit-source-id: 5980b1080734bdae496a18071a2c2b5887c67d85
2020-07-22 08:55:02 -07:00
wenh
226d1f9c73 extend listener callback functions to more file I/O operations (#7055)
Summary:
Currently, `EventListener` in listner.h only have callback functions for file read and write. One may favor extended callback functions for more file I/O operations like flush, sync and close. This PR tries to add those interface and have them called when appropriate throughout the code base.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7055

Test Plan:
Write an experimental listener with those new callback functions with log output in them; run experiments and check logs to see those functions are actually called.
Default test suits `make check` should also be included.

Reviewed By: riversand963

Differential Revision: D22380624

Pulled By: roghnin

fbshipit-source-id: 4121491d45c2c2aae8c255e7998090559a241c6a
2020-07-07 18:21:18 -07:00
Yanqin Jin
3020df9df5 Remove unnecessary inclusion of version_edit.h in env (#6952)
Summary:
In db_options.c, we should avoid including header files in the `db` directory to avoid introducing unnecessary dependency. The reason why `version_edit.h` has been included in `db_options.cc` is because we need two constants, `kUnknownChecksum` and `kUnknownChecksumFuncName`. We can put these two constants as `constexpr` in the public header `file_checksum.h`.

Test plan (devserver):
make check
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6952

Reviewed By: zhichao-cao

Differential Revision: D21925341

Pulled By: riversand963

fbshipit-source-id: 2902f3b74c97f0cf16c58ad24c095c787c3a40e2
2020-06-07 21:56:55 -07:00
Peter Dillinger
c7aedf1b48 Clean up some code related to file checksums (#6861)
Summary:
* Add missing unit test for schema stability of FileChecksumGenCrc32c
  (previously was only comparing to itself)
* A lot of clarifying comments
* Add some assertions for preconditions
* Rename WritableFileWriter::CalculateFileChecksum -> UpdateFileChecksum
* Simplify FileChecksumGenCrc32c with shared functions
* Implement EndianSwapValue to replace unused EndianTransform

And incidentally since I had trouble with 'make check-format' GitHub action disagreeing with local run,
* Output full diagnostic information when 'make check-format' fails in CI
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6861

Test Plan: new unit test passes before & after other changes

Reviewed By: zhichao-cao

Differential Revision: D21667115

Pulled By: pdillinger

fbshipit-source-id: 6a99970f87605aa024fa540c78cd519ff322c3e6
2020-05-21 08:12:51 -07:00
Zhichao Cao
06a2dcebea Move checksum calculation ahead of memory copy (#6844)
Summary:
Originally, the checksum of appended data in writable file writer is calculated after the data is copied to the buffer. It will not be able to catch the bit flip happens during copy. Move the checksum calculation before it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6844

Test Plan: pass make asan_check

Reviewed By: cheng-chang

Differential Revision: D21576726

Pulled By: zhichao-cao

fbshipit-source-id: 0a062a1f19886f6ea0d4e3f557e6f4b799773254
2020-05-14 14:58:14 -07:00
Zhichao Cao
e8d332d97e Use FileChecksumGenFactory for SST file checksum (#6600)
Summary:
In the current implementation, sst file checksum is calculated by a shared checksum function object, which may make some checksum function hard to be applied here such as SHA1. In this implementation, each sst file will have its own checksum generator obejct, created by FileChecksumGenFactory. User needs to implement its own FilechecksumGenerator and Factory to plugin the in checksum calculation method.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6600

Test Plan: tested with make asan_check

Reviewed By: riversand963

Differential Revision: D20717670

Pulled By: zhichao-cao

fbshipit-source-id: 2a74c1c280ac11a07a1980185b43b671acaa71c6
2020-03-29 15:58:46 -07:00
Zhichao Cao
4246888101 Pass IOStatus to write path and set retryable IO Error as hard error in BG jobs (#6487)
Summary:
In the current code base, we use Status to get and store the returned status from the call. Specifically, for IO related functions, the current Status cannot reflect the IO Error details such as error scope, error retryable attribute, and others. With the implementation of https://github.com/facebook/rocksdb/issues/5761, we have the new Wrapper for IO, which returns IOStatus instead of Status. However, the IOStatus is purged at the lower level of write path and transferred to Status.

The first job of this PR is to pass the IOStatus to the write path (flush, WAL write, and Compaction). The second job is to identify the Retryable IO Error as HardError, and set the bg_error_ as HardError. In this case, the DB Instance becomes read only. User is informed of the Status and need to take actions to deal with it (e.g., call db->Resume()).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6487

Test Plan: Added the testing case to error_handler_fs_test. Pass make asan_check

Reviewed By: anand1976

Differential Revision: D20685017

Pulled By: zhichao-cao

fbshipit-source-id: ff85f042896243abcd6ef37877834e26f36b6eb0
2020-03-27 16:04:43 -07:00
sdong
fdf882ded2 Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433)
Summary:
When dynamically linking two binaries together, different builds of RocksDB from two sources might cause errors. To provide a tool for user to solve the problem, the RocksDB namespace is changed to a flag which can be overridden in build time.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6433

Test Plan: Build release, all and jtest. Try to build with ROCKSDB_NAMESPACE with another flag.

Differential Revision: D19977691

fbshipit-source-id: aa7f2d0972e1c31d75339ac48478f34f6cfcfb3e
2020-02-20 12:09:57 -08:00
Zhichao Cao
4369f2c7bb Checksum for each SST file and stores in MANIFEST (#6216)
Summary:
In the current code base, RocksDB generate the checksum for each block and verify the checksum at usage. Current PR enable SST file checksum. After a SST file is generated by Flush or Compaction, RocksDB generate the SST file checksum and store the checksum value and checksum method name in the vs_info and MANIFEST as part for the FileMetadata.

Added the enable_sst_file_checksum to Options to enable or disable file checksum. Added sst_file_checksum to Options such that user can plugin their own SST file checksum calculate method via overriding the SstFileChecksum class. The checksum information inlcuding uint32_t checksum value and a checksum name (string).  A new tool is added to LDB such that user can dump out a list of file checksum information from MANIFEST. If user enables the file checksum but does not provide the sst_file_checksum instance, RocksDB will use the default crc32checksum implemented in table/sst_file_checksum_crc32c.h
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6216

Test Plan: Added the testing case in table_test and ldb_cmd_test to verify checksum is correct in different level. Pass make asan_check.

Differential Revision: D19171461

Pulled By: zhichao-cao

fbshipit-source-id: b2e53479eefc5bb0437189eaa1941670e5ba8b87
2020-02-10 15:52:52 -08:00
anand76
afa2420c2b Introduce a new storage specific Env API (#5761)
Summary:
The current Env API encompasses both storage/file operations, as well as OS related operations. Most of the APIs return a Status, which does not have enough metadata about an error, such as whether its retry-able or not, scope (i.e fault domain) of the error etc., that may be required in order to properly handle a storage error. The file APIs also do not provide enough control over the IO SLA, such as timeout, prioritization, hinting about placement and redundancy etc.

This PR separates out the file/storage APIs from Env into a new FileSystem class. The APIs are updated to return an IOStatus with metadata about the error, as well as to take an IOOptions structure as input in order to allow more control over the IO.

The user can set both ```options.env``` and ```options.file_system``` to specify that RocksDB should use the former for OS related operations and the latter for storage operations. Internally, a ```CompositeEnvWrapper``` has been introduced that inherits from ```Env``` and redirects individual methods to either an ```Env``` implementation or the ```FileSystem``` as appropriate. When options are sanitized during ```DB::Open```, ```options.env``` is replaced with a newly allocated ```CompositeEnvWrapper``` instance if both env and file_system have been specified. This way, the rest of the RocksDB code can continue to function as before.

This PR also ports PosixEnv to the new API by splitting it into two - PosixEnv and PosixFileSystem. PosixEnv is defined as a sub-class of CompositeEnvWrapper, and threading/time functions are overridden with Posix specific implementations in order to avoid an extra level of indirection.

The ```CompositeEnvWrapper``` translates ```IOStatus``` return code to ```Status```, and sets the severity to ```kSoftError``` if the io_status is retryable. The error handling code in RocksDB can then recover the DB automatically.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5761

Differential Revision: D18868376

Pulled By: anand1976

fbshipit-source-id: 39efe18a162ea746fabac6360ff529baba48486f
2019-12-13 14:48:41 -08:00
sdong
b931f84e56 Divide file_reader_writer.h and .cc (#5803)
Summary:
file_reader_writer.h and .cc contain several files and helper function, and it's hard to navigate. Separate it to multiple files and put them under file/
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5803

Test Plan: Build whole project using make and cmake.

Differential Revision: D17374550

fbshipit-source-id: 10efca907721e7a78ed25bbf74dc5410dea05987
2019-09-16 10:33:51 -07:00