Summary:
To propagate the IOStatus from file reads to RocksDB read logic, some of the existing status needs to be replaced by IOStatus.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8130
Test Plan: make check
Reviewed By: anand1976
Differential Revision: D27440188
Pulled By: zhichao-cao
fbshipit-source-id: bbe7622c2106fe4e46871d60f7c26944e5030d78
Summary:
Return early in case there are zero data blocks when
`BlockBasedTableBuilder::EnterUnbuffered()` is called. This crash can
only be triggered by applying dictionary compression to SST files that
contain only range tombstones. It cannot be triggered by a low buffer
limit alone since we only consider entering unbuffered mode after
buffering a data block causing the limit to be breached, or `Finish()`ing the file. It also cannot
be triggered by a totally empty file because those go through
`Abandon()` rather than `Finish()` so unbuffered mode is never entered.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8141
Test Plan: added a unit test that repro'd the "Floating point exception"
Reviewed By: riversand963
Differential Revision: D27495640
Pulled By: ajkr
fbshipit-source-id: a463cfba476919dc5c5c380800a75a86c31ffa23
Summary:
Added `TableProperties::{fast,slow}_compression_estimated_data_size`.
These properties are present in block-based tables when
`ColumnFamilyOptions::sample_for_compression > 0` and the necessary
compression library is supported when the file is generated. They
contain estimates of what `TableProperties::data_size` would be if the
"fast"/"slow" compression library had been used instead. One
limitation is we do not record exactly which "fast" (ZSTD or Zlib)
or "slow" (LZ4 or Snappy) compression library produced the result.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8139
Test Plan:
- new unit test
- ran `db_bench` with `sample_for_compression=1`; verified the `data_size` property matches the `{slow,fast}_compression_estimated_data_size` when the same compression type is used for the output file compression and the sampled compression
Reviewed By: riversand963
Differential Revision: D27454338
Pulled By: ajkr
fbshipit-source-id: 9529293de93ddac7f03b2e149d746e9f634abac4
Summary:
Which should return 2 long instead of an array.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8098
Reviewed By: mrambacher
Differential Revision: D27308741
Pulled By: jay-zhuang
fbshipit-source-id: 44beea2bd28cf6779b048bebc98f2426fe95e25c
Summary:
At least under MacOS, some things were excluded from the build (like Snappy) because the compilation flags were not passed in correctly. This PR does a few things:
- Passes the EXTRA_CXX/LDFLAGS into build_detect_platform. This means that if some tool (like TBB for example) is not installed in a standard place, it could still be detected by build_detect_platform. In this case, the developer would invoke: "EXTRA_CXXFLAGS=<path to TBB include> EXTRA_LDFLAGS=<path to TBB library> make", and the build script would find the tools in the extra location.
- Changes the compilation tests to use PLATFORM_CXXFLAGS. This change causes the EXTRA_FLAGS passed in to the script to be included in the compilation check. Additionally, flags set by the script itself (like --std=c++11) will be used during the checks.
Validated that the make_platform.mk file generated on Linux does not change with this change. On my MacOS machine, the SNAPPY libraries are now available (they were not before as they required --std=c++11 to build).
I also verified that I can build against TBB installed on my Mac by passing in the EXTRA CXX and LD FLAGS to the location in which TBB is installed.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8111
Reviewed By: jay-zhuang
Differential Revision: D27353516
Pulled By: mrambacher
fbshipit-source-id: b6b378c96dbf678bab1479556dcbcb49c47e807d
Summary:
Fix error_handler_fs_test failure due to statistics, it will fails due to multi-thread running and resume is different.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8136
Test Plan: make check
Reviewed By: akankshamahajan15
Differential Revision: D27448828
Pulled By: zhichao-cao
fbshipit-source-id: b94255c45e9e66e93334b5ca2e4e1bfcba23fc20
Summary:
In DBImpl::CloseHelper, we wait for bg_compaction_scheduled_
and bg_flush_scheduled_ to drop to 0. Unschedule is called prior
to cancel any unscheduled flushes/compactions. It is assumed that
anything in the high priority is a flush, and anything in the low
priority pool is a compaction. This assumption, however, is broken when
the high-pri pool is full.
As a result, bg_compaction_scheduled_ can go < 0 and bg_flush_scheduled_
will remain > 0 and DB can be in hang state.
The fix is, we decrement the `bg_{flush,compaction,bottom_compaction}_scheduled_`
inside the `Unschedule{Flush,Compaction,BottomCompaction}Callback()`s. DB
`mutex_` will make the counts atomic in `Unschedule`.
Related discussion: https://github.com/facebook/rocksdb/issues/7928
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8125
Test Plan: Added new test case which hangs without the fix.
Reviewed By: jay-zhuang
Differential Revision: D27390043
Pulled By: ajkr
fbshipit-source-id: 78a367fba9a59ac5607ad24bd1c46dc16d5ec110
Summary:
thread_id is only unique within a process. If we run the same test-set with multiple processes, it could cause db path collision between 2 runs, error message will be like:
```
...
IO error: While lock file: /tmp/rocksdbtest-501//deletefile_test_8093137327721791717/LOCK: Resource temporarily unavailable
...
```
This is could be likely reproduced by:
```
gtest-parallel ./deletefile_test --gtest_filter=DeleteFileTest.BackgroundPurgeCFDropTest -r 1000 -w 1000
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8124
Reviewed By: ajkr
Differential Revision: D27435195
Pulled By: jay-zhuang
fbshipit-source-id: 850fc72cdb660edf93be9a1ca9327008c16dd720
Summary:
GitHub has detected that a package defined in the
docs/Gemfile.lock file of the facebook/rocksdb repository contains a
security vulnerability.
This patch fixes it by upgrading the version of kramdown to 2.3.1
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8131
Reviewed By: jay-zhuang
Differential Revision: D27418776
Pulled By: akankshamahajan15
fbshipit-source-id: 0a4b0b85922b9958afcbc44560584701b1c6c82d
Summary:
BackupEngine previously had unclear but strict concurrency
requirements that the API user must follow for safe use. Now we make
that clear, by separating operations into "Read," "Append," and "Write"
operations, and specifying which combinations are safe across threads on
the same BackupEngine object (previously none; now all, using a
read-write lock), and which are safe across different BackupEngine
instances open on the same backup_dir.
The changes to backupable_db.h should be backward compatible. It is
mostly about eliminating copies of what should be the same function and
(unsurprisingly) useful documentation comments were often placed on
only one of the two copies. With the re-organization, we are also
grouping different categories of operations. In the future we might add
BackupEngineReadAppendOnly, but that didn't seem necessary.
To mark API Read operations 'const', I had to mark some implementation
functions 'const' and some fields mutable.
Functional changes:
* Added RWMutex locking around public API functions to implement thread
safety on a single object. To avoid future bugs, this is another
internal class layered on top (removing many "override" in
BackupEngineImpl). It would be possible to allow more concurrency
between operations, rather than mutual exclusion, but IMHO not worth the
work.
* Fixed a race between Open() (Initialize()) and CreateNewBackup() for
different objects on the same backup_dir, where Initialize() could
delete the temporary meta file created during CreateNewBackup().
(This was found by the new test.)
Also cleaned up a couple of "status checked" TODOs, and improved a
checksum mismatch error message to include involved files.
Potential follow-up work:
* CreateNewBackup has an API wart because it doesn't tell you the
BackupID it just created, which makes it of limited use in a multithreaded
setting.
* We could also consider a Refresh() function to catch up to
changes made from another BackupEngine object to the same dir.
* Use a lock file to prevent multiple writer BackupEngines, but this
won't work on remote filesystems not supporting lock files.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8115
Test Plan:
new mini-stress test in backup unit tests, run with gcc,
clang, ASC, TSAN, and UBSAN, 100 iterations each.
Reviewed By: ajkr
Differential Revision: D27347589
Pulled By: pdillinger
fbshipit-source-id: 28d82ed2ac672e44085a739ddb19d297dad14b15
Summary:
We have observed rocksdb databases creating info log files with world-writeable permissions.
The reason why the file is created like so is because stdio streams opened with fopen calls use mode 0666, and while normally most systems have a umask of 022, in some occasions (for instance, while running daemons), you may find that the application is running with a less restrictive umask. The result is that when opening the DB, the LOG file would be created with world-writeable perms:
```
$ ls -lh db/
total 6.4M
-rw-r--r-- 1 ibarba users 115 Mar 24 17:41 000004.log
-rw-r--r-- 1 ibarba users 16 Mar 24 17:41 CURRENT
-rw-r--r-- 1 ibarba users 37 Mar 24 17:41 IDENTITY
-rw-r--r-- 1 ibarba users 0 Mar 24 17:41 LOCK
-rw-rw-r-- 1 ibarba users 114K Mar 24 17:41 LOG
-rw-r--r-- 1 ibarba users 514 Mar 24 17:41 MANIFEST-000003
-rw-r--r-- 1 ibarba users 31K Mar 24 17:41 OPTIONS-000018
-rw-r--r-- 1 ibarba users 31K Mar 24 17:41 OPTIONS-000020
```
This diff replaces the fopen call with a regular open() call restricting mode, and then using fdopen to associate an stdio stream with that file descriptor. Resulting in the following files being created:
```
-rw-r--r-- 1 ibarba users 58 Mar 24 18:16 000004.log
-rw-r--r-- 1 ibarba users 16 Mar 24 18:16 CURRENT
-rw-r--r-- 1 ibarba users 37 Mar 24 18:16 IDENTITY
-rw-r--r-- 1 ibarba users 0 Mar 24 18:16 LOCK
-rw-r--r-- 1 ibarba users 111K Mar 24 18:16 LOG
-rw-r--r-- 1 ibarba users 514 Mar 24 18:16 MANIFEST-000003
-rw-r--r-- 1 ibarba users 31K Mar 24 18:16 OPTIONS-000018
-rw-r--r-- 1 ibarba users 31K Mar 24 18:16 OPTIONS-000020
```
With the correct permissions
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8106
Reviewed By: akankshamahajan15
Differential Revision: D27415377
Pulled By: mrambacher
fbshipit-source-id: 97ac6c215700a7ea306f4a1fdf9fcf64a3cbb202
Summary:
If the platform is ppc64 and the libc is not GNU libc, then we exclude the range_tree from compilation.
See https://jira.percona.com/browse/PS-7559
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8070
Reviewed By: jay-zhuang
Differential Revision: D27246004
Pulled By: mrambacher
fbshipit-source-id: 59d8433242ce7ce608988341becb4f83312445f5
Summary:
The check in db_bench for table_cache_numshardbits was 0 < bits <= 20, whereas the check in LRUCache was 0 < bits < 20. Changed the two values to match to avoid a crash in db_bench on a null cache.
Fixes https://github.com/facebook/rocksdb/issues/7393
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8110
Reviewed By: zhichao-cao
Differential Revision: D27353522
Pulled By: mrambacher
fbshipit-source-id: a414bd23b5bde1f071146b34cfca5e35c02de869
Summary:
Ran a spell check over the comments in the include/rocksdb directory and fixed any mis-spellings.
There are still some variable names that are spelled incorrectly (like SizeApproximationOptions::include_memtabtles, SstFileMetaData::oldest_ancester_time) that were not fixed, as those would break compilation.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8120
Reviewed By: zhichao-cao
Differential Revision: D27366034
Pulled By: mrambacher
fbshipit-source-id: 6a3f3674890bb6acc751e9c5887a8fbb6adca5df
Summary:
Currently, partitioned filter does not support user-defined timestamp. Disable it for now in ts stress test so that
the contrun jobs can proceed.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8127
Test Plan: make crash_test_with_ts
Reviewed By: ajkr
Differential Revision: D27388488
Pulled By: riversand963
fbshipit-source-id: 5ccff18121cb537bd82f2ac072cd25efb625c666
Summary:
Because build_version.cc is dependent on the library objects (to force a re-generation of it), the library objects would be built in order to satisfy this rule. Because there is a build_version.d file, it would need generated and included.
Change the ALL_DEPS/FILES to not include build_version.cc (meaning no .d file for it, which is okay since it is generated). Also changed the rule on whether or not to generate DEP files to skip tags.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8097
Reviewed By: ajkr
Differential Revision: D27299815
Pulled By: mrambacher
fbshipit-source-id: 1efbe8a56d062f57ae13b6c2944ad3faf775087e
Summary:
Currently, we only truncate the latest alive WAL files when the DB is opened. If the latest WAL file is empty or was flushed during Open, its not truncated since the file will be deleted later on in the Open path. However, before deletion, a new WAL file is created, and if the process crash loops between the new WAL file creation and deletion of the old WAL file, the preallocated space will keep accumulating and eventually use up all disk space. To prevent this, always truncate the latest WAL file, even if its empty or the data was flushed.
Tests:
Add unit tests to db_wal_test
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8122
Reviewed By: riversand963
Differential Revision: D27366132
Pulled By: anand1976
fbshipit-source-id: f923cc03ef033ccb32b140d36c6a63a8152f0e8e
Summary:
For some branches, I see an error during analyze on this code. I do not know why it is not persistent, but this should address the error:
Logic error | Result of operation is garbage or undefined | trace_replay.cc | Replay | 436 | 30 | View Report
DecodeCFAndKey(trace.payload, &get_payload.cf_id, &get_payload.get_key);
--
433 | } else {
434 | TracerHelper::DecodeGetPayload(&trace, &get_payload);
| 25←Calling 'TracerHelper::DecodeGetPayload'→ | 25 | ← | Calling 'TracerHelper::DecodeGetPayload' | →
25 | ← | Calling 'TracerHelper::DecodeGetPayload' | →
| 29←Returning from 'TracerHelper::DecodeGetPayload'→ | 29 | ← | Returning from 'TracerHelper::DecodeGetPayload' | →
29 | ← | Returning from 'TracerHelper::DecodeGetPayload' | →
435 | }
436 | if (get_payload.cf_id > 0 &&
| 30←The left operand of '>' is a garbage value | 30 | ← | The left operand of '>' is a garbage value
30 | ← | The left operand of '>' is a garbage value
437 | cf_map_.find(get_payload.cf_id) == cf_map_.end()) {
438 | return Status::Corruption("Invalid Column Family ID.");
439 | }
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8121
Reviewed By: zhichao-cao
Differential Revision: D27366022
Pulled By: mrambacher
fbshipit-source-id: 309c05dbab08cd7ab7f15389e8456f09196f37f6
Summary:
The snapshot structure returned by rocksdb_transaction_get_snapshot is
supposed to be freed by calling rocksdb_free(), so allocate using malloc
rather than new. Fixes https://github.com/facebook/rocksdb/issues/6112
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8114
Reviewed By: akankshamahajan15
Differential Revision: D27362923
Pulled By: anand1976
fbshipit-source-id: e93a8b1ffe26dafbe22529907f72b796ae971214
Summary:
The patch adds a resource management/RAII class called `ThreadGuard`,
which can be used to ensure that the managed thread is joined when the
`ThreadGuard` is destroyed, regardless of whether it is due to the
object going out of scope, an early return, an exception etc. This is
important because if an `std::thread` object is destroyed without having
been joined (or detached) first, the process is aborted (via
`std::terminate`).
For now, `ThreadGuard` is only used in the test case
`ExternalSSTFileTest.PickedLevelBug`; however, it could come in handy
elsewhere in the codebase as well (both in test code and "real" code).
Case in point: in the `PickedLevelBug` test case, with the earlier code we
could end up in the above situation when the following assertion (which is
before the threads are joined) is triggered:
```
ASSERT_FALSE(bg_compact_started.load());
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8112
Test Plan:
```
make check
gtest-parallel --repeat=10000 ./external_sst_file_test --gtest_filter="*PickedLevelBug"
```
Reviewed By: riversand963
Differential Revision: D27343185
Pulled By: ltamasi
fbshipit-source-id: 2a8c3aa68bc78cc03ec0dbae909fb25c2cd15c69
Summary:
There is bug in the current code base introduced in https://github.com/facebook/rocksdb/issues/8049 , we still set the SST file write IO Error only case as hard error. Fix it by removing the logic.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8107
Test Plan: make check, error_handler_fs_test
Reviewed By: anand1976
Differential Revision: D27321422
Pulled By: zhichao-cao
fbshipit-source-id: c014afc1553ca66b655e3bbf9d0bf6eb417ccf94
Summary:
Previously it only applied to block-based tables generated by flush. This restriction
was undocumented and blocked a new use case. Now compression sampling
applies to all block-based tables we generate when it is enabled.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8105
Test Plan: new unit test
Reviewed By: riversand963
Differential Revision: D27317275
Pulled By: ajkr
fbshipit-source-id: cd9fcc5178d6515e8cb59c6facb5ac01893cb5b0
Summary:
`strerror()` is not thread-safe, using `strerror_r()` instead. The API could be different on the different platforms, used the code from 0deef031cb/folly/String.cpp (L457)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8087
Reviewed By: mrambacher
Differential Revision: D27267151
Pulled By: jay-zhuang
fbshipit-source-id: 4b8856d1ec069d5f239b764750682c56e5be9ddb
Summary:
**Summary:**
When doing CompactFiles on the files of multiple levels(num_level > 2) with L0 is included, the compaction would fail like this.
The reason is that in `VerifyCompactionFileConsistency` it checks the levels between the L0 and base level should be empty, but it regards the compaction triggered by `CompactFiles` as an L0 -> base level compaction wrongly.
The condition is committed several years ago, whereas it isn't correct anymore.
```c++
if (vstorage->compaction_style_ == kCompactionStyleLevel &&
c->start_level() == 0 && c->num_input_levels() > 2U)
```
So this PR just deletes the incorrect check.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8024
Test Plan: make check
Reviewed By: jay-zhuang
Differential Revision: D26907060
Pulled By: ajkr
fbshipit-source-id: 538cef32faf464cd422e3f8de236ea3e58880c2b
Summary:
Improved handling of -bits_per_key other than 10, but at least
the OptimizeForMemory test is simply not designed for generally handling
other settings. (ribbon_test does have a statistical framework for this
kind of testing, but it's not important to do that same for Bloom right
now.)
Closes https://github.com/facebook/rocksdb/issues/7019
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8093
Test Plan: for I in `seq 1 20`; do ./bloom_test --gtest_filter=-*OptimizeForMemory* --bits_per_key=$I &> /dev/null || echo FAILED; done
Reviewed By: mrambacher
Differential Revision: D27275875
Pulled By: pdillinger
fbshipit-source-id: 7362e8ac2c41ea11f639412e4f30c8b375f04388
Summary:
Fix race condition in
DBSSTTest.DBWithMaxSpaceAllowedWithBlobFiles where background flush
thread updates delete_blob_file but in test thread Flush() already
completes after getting bg_error and delete_blob_file remains false.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8092
Test Plan: Ran ASAN job few times on CircleCI
Reviewed By: riversand963
Differential Revision: D27275815
Pulled By: akankshamahajan15
fbshipit-source-id: 2939ad1671403881573bbe07c71aa474c5019130
Summary:
As title. All core db implementations should stay in db_impl.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8082
Test Plan: make check
Reviewed By: ajkr
Differential Revision: D27211442
Pulled By: riversand963
fbshipit-source-id: e0953fde75064740e899aaff7989ff033b7f5232
Summary:
Fix the following error while running `make crash_test`
```
Traceback (most recent call last):
File "tools/db_crashtest.py", line 705, in <module>
main()
File "tools/db_crashtest.py", line 696, in main
blackbox_crash_main(args, unknown_args)
File "tools/db_crashtest.py", line 479, in blackbox_crash_main
+ list({'db': dbname}.items())), unknown_args)
File "tools/db_crashtest.py", line 414, in gen_cmd
finalzied_params = finalize_and_sanitize(params)
File "tools/db_crashtest.py", line 331, in finalize_and_sanitize
dest_params.get("user_timestamp_size") > 0):
TypeError: '>' not supported between instances of 'NoneType' and 'int'
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8091
Test Plan: make crash_test
Reviewed By: ltamasi
Differential Revision: D27268276
Pulled By: riversand963
fbshipit-source-id: ed2873b9587ecc51e24abc35ef2bd3d91fb1ed1b
Summary:
This is a small fix to what I think is a mistype in two comments in `DBOptionsInterface.java`. If it was not an error, feel free to close.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8086
Reviewed By: ajkr
Differential Revision: D27260488
Pulled By: mrambacher
fbshipit-source-id: 469daadaf6039d5b5187132b8e0c7c3672842f21
Summary:
As title.
Always specify namespace::symbol_name...
Test plan
CircleCI and other CI results
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8090
Reviewed By: ltamasi
Differential Revision: D27256130
Pulled By: riversand963
fbshipit-source-id: b9b9ae2b3a8b4a16f0384292e71c6aecca93c570
Summary:
Add some basic test for user-defined timestamp to db_stress. Currently,
read with timestamp always tries to read using the current timestamp.
Due to the per-key timestamp-sequence ordering constraint, we only add timestamp-
related tests to the `NonBatchedOpsStressTest` since this test serializes accesses
to the same key and uses a file to cross-check data correctness.
The timestamp feature is not supported in a number of components, e.g. Merge, SingleDelete,
DeleteRange, CompactionFilter, Readonly instance, secondary instance, SST file ingestion, transaction,
etc. Therefore, db_stress should exit if user enables both timestamp and these features at the same
time. The (currently) incompatible features can be found in
`CheckAndSetOptionsForUserTimestamp`.
This PR also fixes a bug triggered when timestamp is enabled together with
`index_type=kBinarySearchWithFirstKey`. This bug fix will also be in another separate PR
with more unit tests coverage. Fixing it here because I do not want to exclude the index type
from crash test.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8061
Test Plan: make crash_test_with_ts
Reviewed By: jay-zhuang
Differential Revision: D27056282
Pulled By: riversand963
fbshipit-source-id: c3e00ad1023fdb9ebbdf9601ec18270c5e2925a9
Summary:
Since our stress/crash tests by default generate values of size 8, 16, or 24,
it does not make much sense to set `min_blob_size` to 256. The patch
updates the set of potential `min_blob_size` values in the crash test
script and in `db_stress` where it might be set dynamically using
`SetOptions`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8085
Test Plan: Ran `make check` and tried the crash test script.
Reviewed By: riversand963
Differential Revision: D27238620
Pulled By: ltamasi
fbshipit-source-id: 4a96f9944b1ed9220d3045c5ab0b34c49009aeee
Summary:
The implementation of TransactionDB::WrapDB() and
TransactionDB::WrapStackableDB() are almost identical, except for the
type of the first argument `db`. This PR adds a new template function in
anonymous namespace, and calls it in the above two functions.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8079
Test Plan: make check
Reviewed By: lth
Differential Revision: D27184575
Pulled By: riversand963
fbshipit-source-id: f2855a6db3a7e897d0d611f7050ca4b696c56a7a
Summary:
This does not add any new public APIs or published
functionality, but adds the ability to read and use (and in tests,
write) backups with a new meta file schema, based on the old schema
but not forward-compatible (before this change). The new schema enables
some capabilities not in the old:
* Explicit versioning, so that users get clean error messages the next
time we want to break forward compatibility.
* Ignoring unrecognized fields (with warning), so that new non-critical
features can be added without breaking forward compatibility.
* Rejecting future "non-ignorable" fields, so that new features critical
to some use-cases could potentially be added outside of linear schema
versions, with broken forward compatibility.
* Fields at the end of the meta file, such as for checksum of the meta
file's contents (up to that point)
* New optional 'size' field for each file, which is checked when present
* Optionally omitting 'crc32' field, so that we aren't required to have
a crc32c checksum for files to take a backup. (E.g. to support backup
via hard links and to better support file custom checksums.)
Because we do not have a JSON parser and to share code, the new schema
is simply derived from the old schema.
BackupEngine code is updated to allow missing checksums in some places,
and to make that easier, `has_checksum` and `verify_checksum_after_work`
are eliminated. Empty `checksum_hex` indicates checksum is unknown. I'm
not too afraid of regressing on data integrity, because
(a) we have pretty good test coverage of corruption detection in backups, and
(b) we are increasingly relying on the DB itself for data integrity rather than
it being an exclusive feature of backups.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8069
Test Plan:
new unit tests, added to crash test (some local run with
boosted backup probability)
Reviewed By: ajkr
Differential Revision: D27139824
Pulled By: pdillinger
fbshipit-source-id: 9e0e4decfb42bb84783d64d2d246456d97e8e8c5
