Summary:
The main challenge to make the memtable garbage collection prototype (nicknamed `mempurge`) was to not get rid of WAL files that contain unflushed (but mempurged) data. That was successfully guaranteed by not writing the VersionEdit to the MANIFEST file after a successful mempurge.
By not writing VersionEdits to the `MANIFEST` file after a succesful mempurge operation, we do not change the earliest log file number that contains unflushed data: `cfd->GetLogNumber()` (`cfd->SetLogNumber()` is only called in `VersionSet::ProcessManifestWrites`). As a result, a number of functions introduced earlier just for the mempurge operation are not obscolete/redundant. (e.g.: `FlushJob::ExtractEarliestLogFileNumber`), and this PR aims at cleaning up all these now-unnecessary functions. In particular, we no longer need to store the earliest log file number in the `MemTable` struct itself. This PR therefore also reverts the `MemTable` struct to its original form.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8558
Test Plan: Already included in `db_flush_test.cc`.
Reviewed By: anand1976
Differential Revision: D29764351
Pulled By: bjlemaire
fbshipit-source-id: 0f43b260fa270251862512f397d3f24ee62e8437
Summary:
In this PR, `mempurge` is made compatible with the Write Ahead Log: in case of recovery, the DB is now capable of recovering the data that was "mempurged" and kept in the `imm()` list of immutable memtables.
The twist was to add a uint64_t to the `memtable` struct to store the number of the earliest log file containing entries from the `memtable`. When a `Flush` operation is replaced with a `MemPurge`, the `VersionEdit` (which usually contains the new min log file number to pick up for recovery and the level 0 file path of the newly created SST file) is no longer appended to the manifest log, and every time the `deleteWal` method is called, a check is made on the list of immutable memtables.
This PR also includes a unit test that verifies that no data is lost upon Reopening of the database when the mempurge feature is activated. This extensive unit test includes two column families, with valid data contained in the imm() at time of "crash"/reopening (recovery).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8528
Reviewed By: pdillinger
Differential Revision: D29701097
Pulled By: bjlemaire
fbshipit-source-id: 072a900fb6ccc1edcf5eef6caf88f3060238edf9
Summary:
Changed fprintf function to fputc in ApplyVersionEdit, and replaced null characters with whitespaces.
Added unit test in ldb_test.py - verifies that manifest_dump --verbose output is correct when keys and values containing null characters are inserted.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8378
Reviewed By: pdillinger
Differential Revision: D29034584
Pulled By: bjlemaire
fbshipit-source-id: 50833687a8a5f726e247c38457eadc3e6dbab862
Summary:
RocksDB allows user-specified custom comparators which may not be known to `ldb`,
a built-in tool for checking/mutating the database. Therefore, column family comparator
names mismatch encountered during manifest dump should not prevent the dumping from
proceeding.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8216
Test Plan:
```
make check
```
Also manually do the following
```
KEEP_DB=1 ./db_with_timestamp_basic_test
./ldb --db=<db> manifest_dump --verbose
```
The ldb should succeed and print something like:
```
...
--------------- Column family "default" (ID 0) --------------
log number: 6
comparator: <TestComparator>, but the comparator object is not available.
...
```
Reviewed By: ltamasi
Differential Revision: D27927581
Pulled By: riversand963
fbshipit-source-id: f610b2c842187d17f575362070209ee6b74ec6d4
Summary:
If `options.best_efforts_recovery == true`, RocksDB currently tolerates missing table files and recovers to the latest version without missing table files (not considering WAL). It is necessary to handle blob files as well to make the feature more complete.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8180
Test Plan: make check
Reviewed By: ltamasi
Differential Revision: D27840556
Pulled By: riversand963
fbshipit-source-id: 041685d0dc2e7779ac4f0374c07a8a327704aa5e
Summary:
This PR
- adds a class `ManifestTailer` that inherits from `VersionEditHandlerPointInTime`. `ManifestTailer::Iterate()` can be called multiple times to tail the primary instance's MANIFEST and apply the changes to the secondary,
- updates the implementation of `ReactiveVersionSet::ReadAndApply` to use this class,
- removes unused code in version_set.cc,
- updates existing tests, e.g. removing deleted sync points from unit tests,
- adds a new test to address the bug in https://github.com/facebook/rocksdb/issues/7815.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7998
Test Plan:
make check
Existing and newly-added tests in version_set_test.cc and db_secondary_test.cc
Reviewed By: jay-zhuang
Differential Revision: D26926641
Pulled By: riversand963
fbshipit-source-id: 8d4dd15db0ba863c213f743e33b5a207e948c980
Summary:
The checkpointing logic supports passing file level checksums
to the copy_file_cb callback function which is used by the backup code
for detecting corruption during file copies.
However, this is currently implemented only for table files.
This PR extends the checksum retrieval to blob files as well.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8003
Test Plan: Add new test units
Reviewed By: ltamasi
Differential Revision: D26680701
Pulled By: akankshamahajan15
fbshipit-source-id: 1bd1e2464df6e9aa31091d35b8c72786d94cd1c5
Summary:
Following https://github.com/facebook/rocksdb/issues/7655 and https://github.com/facebook/rocksdb/issues/7657, this PR adds `full_history_ts_low_` to `ColumnFamilyData`.
`ColumnFamilyData::full_history_ts_low_` will be used to create `FlushJob` and `CompactionJob`.
`ColumnFamilyData::full_history_ts_low` is persisted to the MANIFEST file. An application can only
increase its value. Consider the following case:
>
> The database has a key at ts=950. `full_history_ts_low` is first set to 1000, and then a GC is triggered
> and cleans up all data older than 1000. If the application sets `full_history_ts_low` to 900 afterwards,
> and tries to read at ts=960, the key at 950 is not seen. From the perspective of the read, the result
> is hard to reason. For simplicity, we just do now allow decreasing full_history_ts_low for now.
>
During recovery, the value of `full_history_ts_low` is restored for each column family if applicable. Note that
version edits in the MANIFEST file for the same column family may have `full_history_ts_low` unsorted due
to the potential interleaving of `LogAndApply` calls. Only the max will be used to restore the state of the
column family.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7740
Test Plan: make check
Reviewed By: ltamasi
Differential Revision: D25296217
Pulled By: riversand963
fbshipit-source-id: 24acda1df8262cd7cfdc6ce7b0ec56438abe242a
Summary:
Added a few classes in the same class hierarchy to remove code duplication and
refactor the logic of reading and processing MANIFEST files.
New classes are as follows.
```
class VersionEditHandlerBase;
class ListColumnFamiliesHandler : VersionEditHandlerBase;
class FileChecksumRetriever : VersionEditHandlerBase;
class DumpManifestHandler : VersionEditHandler;
```
Classes that already existed before this PR are as follows.
```
class VersionEditHandler : VersionEditHandlerBase;
```
With these classes, refactored functions: `VersionSet::Recover()`,
`VersionSet::ListColumnFamilies()`, `VersionSet::DumpManifest()`,
`GetFileChecksumFromManifest()`.
Test Plan (devserver):
```
make check
COMPILE_WITH_ASAN=1 make check
```
These refactored code, especially recovery-related logic, will be tested intensively by
all existing unit tests and stress tests. For example, run
```
make crash_test
```
Verified 3 successful runs on devserver.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6581
Reviewed By: ajkr
Differential Revision: D20616217
Pulled By: riversand963
fbshipit-source-id: 048c7743aa4be2623ccd0cc3e61c0027e604e78b
Summary:
When a WAL is synced, an edit is written to MANIFEST.
After flushing memtables, the obsoleted WALs are piggybacked to MANIFEST while writing the new L0 files to MANIFEST.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7601
Test Plan:
`track_and_verify_wals_in_manifest` is enabled by default for all tests extending `DBBasicTest`, and in db_stress_test.
Unit test `wal_edit_test`, `version_edit_test`, and `version_set_test` are also updated.
Watch all tests to pass.
Reviewed By: ltamasi
Differential Revision: D24553957
Pulled By: cheng-chang
fbshipit-source-id: 66a569ff1bdced38e22900bd240b73113906e040
Summary:
This PR makes it able to `LogAndApply` `VersionEdit`s related to WALs, and also be able to `Recover` from MANIFEST with WAL related `VersionEdit`s.
The `VersionEdit`s related to WAL are treated similarly as those related to column family operations, they are not applied to versions, but can be in a commit group. Mixing WAL related `VersionEdit`s with other types of edits will make logic in `ProcessManifestWrite` more complicated, so `VersionEdit`s related to WAL can either be WAL additions or deletions, like column family add and drop.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7256
Test Plan: a set of unit tests are added in `version_set_test.cc`
Reviewed By: riversand963
Differential Revision: D23123238
Pulled By: cheng-chang
fbshipit-source-id: 246be2ed4744fd03fa2738aba408aaa611d0379c
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
Summary:
https://github.com/facebook/rocksdb/issues/5411 refactored `VersionSet::Recover` but introduced a bug, explained as follows.
Before, once a checksum mismatch happens, `reporter` will set `s` to be non-ok. Therefore, Recover will stop processing the MANIFEST any further.
```
// Correct
// Inside Recover
LogReporter reporter;
reporter.status = &s;
log::Reader reader(..., reporter);
while (reader.ReadRecord() && s.ok()) {
...
}
```
The bug is that, the local variable `s` in `ReadAndRecover` won't be updated by `reporter` while reading the MANIFEST. It is possible that the reader sees a checksum mismatch in a record, but `ReadRecord` retries internally read and finds the next valid record. The mismatched record will be ignored and no error is reported.
```
// Incorrect
// Inside Recover
LogReporter reporter;
reporter.status = &s;
log::Reader reader(..., reporter);
s = ReadAndRecover(reader, ...);
// Inside ReadAndRecover
Status s; // Shadows the s in Recover.
while (reader.ReadRecord() && s.ok()) {
...
}
```
`LogReporter` can use a separate `log_read_status` to track the errors while reading the MANIFEST. RocksDB can process more MANIFEST entries only if `log_read_status.ok()`.
Test plan (devserver):
make check
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6996
Reviewed By: ajkr
Differential Revision: D22105746
Pulled By: riversand963
fbshipit-source-id: b22f717a423457a41ca152a242abbb64cf91fc38
Summary:
In best-efforts recovery, an error that is not Corruption or IOError::kNotFound or IOError::kPathNotFound will be overwritten silently. Fix this by checking all non-ok cases and return early.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6989
Test Plan: make check
Reviewed By: ajkr
Differential Revision: D22071418
Pulled By: riversand963
fbshipit-source-id: 5a4ea5dfb1a41f41c7a3fdaf62b163007b42f04b
Summary:
Memory pinned by `pin_l0_filter_and_index_blocks_in_cache` needs to be predictable based on user config. This PR makes sure
we do not pin extra memory for large files generated by intra-L0 (see https://github.com/facebook/rocksdb/issues/6889).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6911
Test Plan: unit test
Reviewed By: siying
Differential Revision: D21835818
Pulled By: ajkr
fbshipit-source-id: a11a088549d06bed8aacc2548d266e5983f0ead4
Summary:
1. Update column_family_memtables_ to point to latest column_family_set in
version_set after recovery.
2. Normalize file paths passed by application so that directories end with '/'
or '\\'.
3. In addition to missing files, corrupted files are also ignored in
best-efforts recovery.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6824
Test Plan: COMPILE_WITH_ASAN=1 make check
Reviewed By: anand1976
Differential Revision: D21463905
Pulled By: riversand963
fbshipit-source-id: c48db8843cc93c8c1c7139c474b64e6f775307d2
Summary:
With consistency check enabled, VersionBuilder::SaveTo() may return error once
corruption is detected while building versions. We should handle these errors.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6801
Test Plan: make check
Reviewed By: siying
Differential Revision: D21385045
Pulled By: riversand963
fbshipit-source-id: 98f6424e2a4699b62befa21e9fe00e70a771118e
Summary:
There are situations when RocksDB tries to recover, but the db is in an inconsistent state due to SST files referenced in the MANIFEST being missing. In this case, previous RocksDB will just fail the recovery and return a non-ok status.
This PR enables another possibility. During recovery, RocksDB checks possible MANIFEST files, and try to recover to the most recent state without missing table file. `VersionSet::Recover()` applies version edits incrementally and "materializes" a version only when this version does not reference any missing table file. After processing the entire MANIFEST, the version created last will be the latest version.
`DBImpl::Recover()` calls `VersionSet::Recover()`. Afterwards, WAL replay will *not* be performed.
To use this capability, set `options.best_efforts_recovery = true` when opening the db. Best-efforts recovery is currently incompatible with atomic flush.
Test plan (on devserver):
```
$make check
$COMPILE_WITH_ASAN=1 make all && make check
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6334
Reviewed By: anand1976
Differential Revision: D19778960
Pulled By: riversand963
fbshipit-source-id: c27ea80f29bc952e7d3311ecf5ee9c54393b40a8
