Commit Graph

46 Commits

Author SHA1 Message Date
Akanksha Mahajan
ae82d91492 Remove corrupted WAL files in kPointRecoveryMode with avoid_flush_duing_recovery set true (#9634)
Summary:
1) In case of non-TransactionDB and avoid_flush_during_recovery = true, RocksDB won't
flush the data from WAL to L0 for all column families if possible. As a
result, not all column families can increase their log_numbers, and
min_log_number_to_keep won't change.
2) For transaction DB (.allow_2pc), even with the flush, there may be old WAL files that it must not delete because they can contain data of uncommitted transactions and min_log_number_to_keep won't change.

If we persist a new MANIFEST with
advanced log_numbers for some column families, then during a second
crash after persisting the MANIFEST, RocksDB will see some column
families' log_numbers larger than the corrupted wal, and the "column family inconsistency" error will be hit, causing recovery to fail.

As a solution,
1. the corrupted WALs whose numbers are larger than the
corrupted wal and smaller than the new WAL will be moved to archive folder.
2. Currently, RocksDB DB::Open() may creates and writes to two new MANIFEST files even before recovery succeeds. This PR buffers the edits in a structure and writes to a new MANIFEST after recovery is successful

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9634

Test Plan:
1. Added new unit tests
                2. make crast_test -j

Reviewed By: riversand963

Differential Revision: D34463666

Pulled By: akankshamahajan15

fbshipit-source-id: e233d3af0ed4e2028ca0cf051e5a334a0fdc9d19
2022-04-11 15:39:31 -07:00
Yanqin Jin
e0c84aa0dc Fix a race condition in WAL tracking causing DB open failure (#9715)
Summary:
There is a race condition if WAL tracking in the MANIFEST is enabled in a database that disables 2PC.

The race condition is between two background flush threads trying to install flush results to the MANIFEST.

Consider an example database with two column families: "default" (cfd0) and "cf1" (cfd1). Initially,
both column families have one mutable (active) memtable whose data backed by 6.log.

1. Trigger a manual flush for "cf1", creating a 7.log
2. Insert another key to "default", and trigger flush for "default", creating 8.log
3. BgFlushThread1 finishes writing 9.sst
4. BgFlushThread2 finishes writing 10.sst

```
Time  BgFlushThread1                                    BgFlushThread2
 |    mutex_.Lock()
 |    precompute min_wal_to_keep as 6
 |    mutex_.Unlock()
 |                                                     mutex_.Lock()
 |                                                     precompute min_wal_to_keep as 6
 |                                                     join MANIFEST write queue and mutex_.Unlock()
 |    write to MANIFEST
 |    mutex_.Lock()
 |    cfd1->log_number = 7
 |    Signal bg_flush_2 and mutex_.Unlock()
 |                                                     wake up and mutex_.Lock()
 |                                                     cfd0->log_number = 8
 |                                                     FindObsoleteFiles() with job_context->log_number == 7
 |                                                     mutex_.Unlock()
 |                                                     PurgeObsoleteFiles() deletes 6.log
 V
```

As shown in the above, BgFlushThread2 thinks that the min wal to keep is 6.log because "cf1" has unflushed data in 6.log (cf1.log_number=6).
Similarly, BgThread1 thinks that min wal to keep is also 6.log because "default" has unflushed data (default.log_number=6).
No WAL deletion will be written to MANIFEST because 6 is equal to `versions_->wals_.min_wal_number_to_keep`,
due to https://github.com/facebook/rocksdb/blob/7.1.fb/db/memtable_list.cc#L513:L514.
The bg flush thread that finishes last will perform file purging. `job_context.log_number` will be evaluated as 7, i.e.
the min wal that contains unflushed data, causing 6.log to be deleted. However, MANIFEST thinks 6.log should still exist.
If you close the db at this point, you won't be able to re-open it if `track_and_verify_wal_in_manifest` is true.

We must handle the case of multiple bg flush threads, and it is difficult for one bg flush thread to know
the correct min wal number until the other bg flush threads have finished committing to the manifest and updated
the `cfd::log_number`.
To fix this issue, we rename an existing variable `min_log_number_to_keep_2pc` to `min_log_number_to_keep`,
and use it to track WAL file deletion in non-2pc mode as well.
This variable is updated only 1) during recovery with mutex held, or 2) in the MANIFEST write thread.
`min_log_number_to_keep` means RocksDB will delete WALs below it, although there may be WALs
above it which are also obsolete. Formally, we will have [min_wal_to_keep, max_obsolete_wal]. During recovery, we
make sure that only WALs above max_obsolete_wal are checked and added back to `alive_log_files_`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9715

Test Plan:
```
make check
```
Also ran stress test below (with asan) to make sure it completes successfully.
```
TEST_TMPDIR=/dev/shm/rocksdb OPT=-g ASAN_OPTIONS=disable_coredump=0 \
CRASH_TEST_EXT_ARGS=--compression_type=zstd SKIP_FORMAT_BUCK_CHECKS=1 \
make J=52 -j52 blackbox_asan_crash_test
```

Reviewed By: ltamasi

Differential Revision: D34984412

Pulled By: riversand963

fbshipit-source-id: c7b21a8d84751bb55ea79c9f387103d21b231005
2022-03-23 19:41:31 -07:00
Yanqin Jin
1cda273dc3 Fix a silent data loss for write-committed txn (#9571)
Summary:
The following sequence of events can cause silent data loss for write-committed
transactions.
```
Time    thread 1                                       bg flush
 |   db->Put("a")
 |   txn = NewTxn()
 |   txn->Put("b", "v")
 |   txn->Prepare()       // writes only to 5.log
 |   db->SwitchMemtable() // memtable 1 has "a"
 |                        // close 5.log,
 |                        // creates 8.log
 |   trigger flush
 |                                                  pick memtable 1
 |                                                  unlock db mutex
 |                                                  write new sst
 |   txn->ctwb->Put("gtid", "1") // writes 8.log
 |   txn->Commit() // writes to 8.log
 |                 // writes to memtable 2
 |                                               compute min_log_number_to_keep_2pc, this
 |                                               will be 8 (incorrect).
 |
 |                                             Purge obsolete wals, including 5.log
 |
 V
```

At this point, writes of txn exists only in memtable. Close db without flush because db thinks the data in
memtable are backed by log. Then reopen, the writes are lost except key-value pair {"gtid"->"1"},
only the commit marker of txn is in 8.log

The reason lies in `PrecomputeMinLogNumberToKeep2PC()` which calls `FindMinPrepLogReferencedByMemTable()`.
In the above example, when bg flush thread tries to find obsolete wals, it uses the information
computed by `PrecomputeMinLogNumberToKeep2PC()`. The return value of `PrecomputeMinLogNumberToKeep2PC()`
depends on three components
- `PrecomputeMinLogNumberToKeepNon2PC()`. This represents the WAL that has unflushed data. As the name of this method suggests, it does not account for 2PC. Although the keys reside in the prepare section of a previous WAL, the column family references the current WAL when they are actually inserted into the memtable during txn commit.
- `prep_tracker->FindMinLogContainingOutstandingPrep()`. This represents the WAL with a prepare section but the txn hasn't committed.
- `FindMinPrepLogReferencedByMemTable()`. This represents the WAL on which some memtables (mutable and immutable) depend for their unflushed data.

The bug lies in `FindMinPrepLogReferencedByMemTable()`. Originally, this function skips checking the column families
that are being flushed, but the unit test added in this PR shows that they should not be. In this unit test, there is
only the default column family, and one of its memtables has unflushed data backed by a prepare section in 5.log.
We should return this information via `FindMinPrepLogReferencedByMemTable()`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9571

Test Plan:
```
./transaction_test --gtest_filter=*/TransactionTest.SwitchMemtableDuringPrepareAndCommit_WC/*
make check
```

Reviewed By: siying

Differential Revision: D34235236

Pulled By: riversand963

fbshipit-source-id: 120eb21a666728a38dda77b96276c6af72b008b1
2022-02-16 23:08:58 -08:00
Peter Dillinger
2a67d475f1 Fix bug affecting GetSortedWalFiles, Backups, Checkpoint (#9208)
Summary:
Saw error like this:
`Backup failed -- IO error: No such file or directory: While opening a
file for sequentially reading:
/dev/shm/rocksdb/rocksdb_crashtest_blackbox/004426.log: No such file or
directory`

Unfortunately, GetSortedWalFiles (used by Backups, Checkpoint, etc.)
relies on no file deletions happening while its operating, which
means not only disabling (more) deletions, but ensuring any pending
deletions are completed. Two fixes related to this:

* There was a gap in several places between decrementing
pending_purge_obsolete_files_ and incrementing bg_purge_scheduled_ where
the db mutex would be released and GetSortedWalFiles (and others) could
get false information that no deletions are pending.

* The fix to https://github.com/facebook/rocksdb/issues/8591 (disabling deletions in GetSortedWalFiles) seems
incomplete because it doesn't prevent pending deletions from occuring
during the operation (if deletions not already disabled, the case that
was to be fixed by the change).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9208

Test Plan:
existing tests (it's hard to write a test for interleavings
that are now excluded - this is what stress test is for)

Reviewed By: ajkr

Differential Revision: D32630675

Pulled By: pdillinger

fbshipit-source-id: a121e3da648de130cd24d44c524232f4eb22f178
2021-11-24 14:52:00 -08:00
Jay Zhuang
29102641dd Skip directory fsync for filesystem btrfs (#8903)
Summary:
Directory fsync might be expensive on btrfs and it may not be needed.
Here are 4 directory fsync cases:
1. creating a new file: dir-fsync is not needed on btrfs, as long as the
   new file itself is synced.
2. renaming a file: dir-fsync is not needed if the renamed file is
   synced. So an API `FsyncAfterFileRename(filename, ...)` is provided
   to sync the file on btrfs. By default, it just calls dir-fsync.
3. deleting files: dir-fsync is forced by set
   `IOOptions.force_dir_fsync = true`
4. renaming multiple files (like backup and checkpoint): dir-fsync is
   forced, the same as above.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8903

Test Plan: run tests on btrfs and non btrfs

Reviewed By: ajkr

Differential Revision: D30885059

Pulled By: jay-zhuang

fbshipit-source-id: dd2730b31580b0bcaedffc318a762d7dbf25de4a
2021-11-03 12:21:27 -07:00
anand76
532ff334d9 Don't ignore deletion rate limit if WAL dir is different (#8967)
Summary:
If WAL dir is different from the DB dir, we should still honor the SstFileManager deletion rate limit for SST files.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8967

Test Plan: Add a new unit test in db_sst_test

Reviewed By: pdillinger

Differential Revision: D31220116

Pulled By: anand1976

fbshipit-source-id: bcde8a53a7d728e15e597fb5d07ee86c1b38bd28
2021-09-30 13:26:31 -07:00
mrambacher
13ae16c315 Cleanup includes in dbformat.h (#8930)
Summary:
This header file was including everything and the kitchen sink when it did not need to.  This resulted in many places including this header when they needed other pieces instead.

Cleaned up this header to only include what was needed and fixed up the remaining code to include what was now missing.

Hopefully, this sort of code hygiene cleanup will speed up the builds...

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8930

Reviewed By: pdillinger

Differential Revision: D31142788

Pulled By: mrambacher

fbshipit-source-id: 6b45de3f300750c79f751f6227dece9cfd44085d
2021-09-29 04:04:40 -07:00
Akanksha Mahajan
d6aa8c49f8 Expose blob file information through the EventListener interface (#8675)
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
2021-09-16 17:23:36 -07:00
Peter Dillinger
c9cd5d25a8 Remove some unneeded code (#8736)
Summary:
* FullKey and ParseFullKey appear to serve no purpose in the public API
(or anything else) so removed. Only use in one test updated.
* NumberToString serves no purpose vs. ToString so removed, numerous
calls updated
* Remove unnecessary forward declarations in metadata.h by re-arranging
class definitions.
* Remove some unneeded semicolons

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8736

Test Plan: existing tests

Reviewed By: mrambacher

Differential Revision: D30700039

Pulled By: pdillinger

fbshipit-source-id: 1e436a576f511a6ed8b4d97af7cc8216bc729af2
2021-09-01 14:28:58 -07:00
Levi Tamasi
9b25d26dc8 Attempt to deflake ObsoleteFilesTest.DeleteObsoleteOptionsFile (#8624)
Summary:
We've been seeing occasional crashes on CI while inserting into the
vectors in `ObsoleteFilesTest.DeleteObsoleteOptionsFile`. The crashes
don't reproduce locally (could be either a race or an object lifecycle
issue) but the good news is that the vectors in question are not really
used for anything meaningful by the test. (The assertion about the sizes
of the two vectors being equal is guaranteed to hold, since the two sync
points where they are populated are right after each other.) The patch
simply removes the vectors from the test, alongside the associated
callbacks and sync points.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8624

Test Plan: `make check`

Reviewed By: akankshamahajan15

Differential Revision: D30118485

Pulled By: ltamasi

fbshipit-source-id: 0a4c3d06584e84cd2b1dcc212d274fa1b89cb647
2021-08-05 18:36:16 -07:00
mrambacher
ab7f7c9e49 Allow WAL dir to change with db dir (#8582)
Summary:
Prior to this change, the "wal_dir"  DBOption would always be set (defaults to dbname) when the DBOptions were sanitized.  Because of this setitng in the options file, it was not possible to rename/relocate a database directory after it had been created and use the existing options file.

After this change, the "wal_dir" option is only set under specific circumstances.  Methods were added to the ImmutableDBOptions class to see if it is set and if it is set to something other than the dbname.  Additionally, a method was added to retrieve the effective value of the WAL dir (either the option or the dbname/path).

Tests were added to the core and ldb to test that a database could be created and renamed without issue.  Additional tests for various permutations of wal_dir were also added.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8582

Reviewed By: pdillinger, autopear

Differential Revision: D29881122

Pulled By: mrambacher

fbshipit-source-id: 67d3d033dc8813d59917b0a3fba2550c0efd6dfb
2021-07-30 12:16:44 -07:00
sdong
e8f218cb68 DB::GetSortedWalFiles() to ensure file deletion is disabled (#8591)
Summary:
If DB::GetSortedWalFiles() runs without file deletion disbled, file might get deleted in the middle and error is returned to users. It makes the function hard to use. Fix it by disabling file deletion if it is not done.

Fix another minor issue of logging within DB mutex, which should not be done unless a major failure happens.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8591

Test Plan: Run all existing tests

Reviewed By: pdillinger

Differential Revision: D29969412

fbshipit-source-id: d5f42b5271608a35b9b07687ce18157d7447b0de
2021-07-29 11:51:08 -07:00
mrambacher
01e460d538 Make types of Immutable/Mutable Options fields match that of the underlying Option (#8176)
Summary:
This PR is a first step at attempting to clean up some of the Mutable/Immutable Options code.  With this change, a DBOption and a ColumnFamilyOption can be reconstructed from their Mutable and Immutable equivalents, respectively.

readrandom tests do not show any performance degradation versus master (though both are slightly slower than the current 6.19 release).

There are still fields in the ImmutableCFOptions that are not CF options but DB options.  Eventually, I would like to move those into an ImmutableOptions (= ImmutableDBOptions+ImmutableCFOptions).  But that will be part of a future PR to minimize changes and disruptions.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8176

Reviewed By: pdillinger

Differential Revision: D27954339

Pulled By: mrambacher

fbshipit-source-id: ec6b805ba9afe6e094bffdbd76246c2d99aa9fad
2021-04-22 20:43:54 -07:00
Yanqin Jin
a376c22066 Handle rename() failure in non-local FS (#8192)
Summary:
In a distributed environment, a file `rename()` operation can succeed on server (remote)
side, but the client can somehow return non-ok status to RocksDB. Possible reasons include
network partition, connection issue, etc. This happens in `rocksdb::SetCurrentFile()`, which
can be called in `LogAndApply() -> ProcessManifestWrites()` if RocksDB tries to switch to a
new MANIFEST. We currently always delete the new MANIFEST if an error occurs.

This is problematic in distributed world. If the server-side successfully updates the CURRENT
file via renaming, then a subsequent `DB::Open()` will try to look for the new MANIFEST and fail.

As a fix, we can track the execution result of IO operations on the new MANIFEST.
- If IO operations on the new MANIFEST fail, then we know the CURRENT must point to the original
  MANIFEST. Therefore, it is safe to remove the new MANIFEST.
- If IO operations on the new MANIFEST all succeed, but somehow we end up in the clean up
  code block, then we do not know whether CURRENT points to the new or old MANIFEST. (For local
  POSIX-compliant FS, it should still point to old MANIFEST, but it does not matter if we keep the
  new MANIFEST.) Therefore, we keep the new MANIFEST.
    - Any future `LogAndApply()` will switch to a new MANIFEST and update CURRENT.
    - If process reopens the db immediately after the failure, then the CURRENT file can point
      to either the new MANIFEST or the old one, both of which exist. Therefore, recovery can
      succeed and ignore the other.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8192

Test Plan: make check

Reviewed By: zhichao-cao

Differential Revision: D27804648

Pulled By: riversand963

fbshipit-source-id: 9c16f2a5ce41bc6aadf085e48449b19ede8423e4
2021-04-19 18:11:13 -07:00
Peter Dillinger
a4e82a3cca Fix read-only DB writing to filesystem with write_dbid_to_manifest (#8164)
Summary:
Fixing another crash test failure in the case of
write_dbid_to_manifest=true and reading a backup as read-only DB.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8164

Test Plan:
enhanced unit test for backup as read-only DB, ran
blackbox_crash_test more with elevated backup_one_in

Reviewed By: zhichao-cao

Differential Revision: D27622237

Pulled By: pdillinger

fbshipit-source-id: 680d0f99ddb465a601737f2e3f2c80efd47384fb
2021-04-07 10:26:47 -07:00
Peter Dillinger
879357fdb0 Make backups openable as read-only DBs (#8142)
Summary:
A current limitation of backups is that you don't know the
exact database state of when the backup was taken. With this new
feature, you can at least inspect the backup's DB state without
restoring it by opening it as a read-only DB.

Rather than add something like OpenAsReadOnlyDB to the BackupEngine API,
which would inhibit opening stackable DB implementations read-only
(if/when their APIs support it), we instead provide a DB name and Env
that can be used to open as a read-only DB.

Possible follow-up work:

* Add a version of GetBackupInfo for a single backup.
* Let CreateNewBackup return the BackupID of the newly-created backup.

Implementation details:

Refactored ChrootFileSystem to split off new base class RemapFileSystem,
which allows more general remapping of files. We use this base class to
implement BackupEngineImpl::RemapSharedFileSystem.

To minimize API impact, I decided to just add these fields `name_for_open`
and `env_for_open` to those set by GetBackupInfo when
include_file_details=true. Creating the RemapSharedFileSystem adds a bit
to the memory consumption, perhaps unnecessarily in some cases, but this
has been mitigated by (a) only initialize the RemapSharedFileSystem
lazily when GetBackupInfo with include_file_details=true is called, and
(b) using the existing `shared_ptr<FileInfo>` objects to hold most of the
mapping data.

To enhance API safety, RemapSharedFileSystem is wrapped by new
ReadOnlyFileSystem which rejects any attempts to write. This uncovered a
couple of places in which DB::OpenForReadOnly would write to the
filesystem, so I fixed these. Added a release note because this affects
logging.

Additional minor refactoring in backupable_db.cc to support the new
functionality.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8142

Test Plan:
new test (run with ASAN and UBSAN), added to stress test and
ran it for a while with amplified backup_one_in

Reviewed By: ajkr

Differential Revision: D27535408

Pulled By: pdillinger

fbshipit-source-id: 04666d310aa0261ef6b2385c43ca793ce1dfd148
2021-04-06 14:37:53 -07:00
mrambacher
3dff28cf9b Use SystemClock* instead of std::shared_ptr<SystemClock> in lower level routines (#8033)
Summary:
For performance purposes, the lower level routines were changed to use a SystemClock* instead of a std::shared_ptr<SystemClock>.  The shared ptr has some performance degradation on certain hardware classes.

For most of the system, there is no risk of the pointer being deleted/invalid because the shared_ptr will be stored elsewhere.  For example, the ImmutableDBOptions stores the Env which has a std::shared_ptr<SystemClock> in it.  The SystemClock* within the ImmutableDBOptions is essentially a "short cut" to gain access to this constant resource.

There were a few classes (PeriodicWorkScheduler?) where the "short cut" property did not hold.  In those cases, the shared pointer was preserved.

Using db_bench readrandom perf_level=3 on my EC2 box, this change performed as well or better than 6.17:

6.17: readrandom   :      28.046 micros/op 854902 ops/sec;   61.3 MB/s (355999 of 355999 found)
6.18: readrandom   :      32.615 micros/op 735306 ops/sec;   52.7 MB/s (290999 of 290999 found)
PR: readrandom   :      27.500 micros/op 871909 ops/sec;   62.5 MB/s (367999 of 367999 found)

(Note that the times for 6.18 are prior to revert of the SystemClock).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8033

Reviewed By: pdillinger

Differential Revision: D27014563

Pulled By: mrambacher

fbshipit-source-id: ad0459eba03182e454391b5926bf5cdd45657b67
2021-03-15 04:34:11 -07:00
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
mrambacher
02418194d7 Add more tests for assert status checked (#7524)
Summary:
Added 10 more tests that pass the ASSERT_STATUS_CHECKED test.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7524

Reviewed By: akankshamahajan15

Differential Revision: D24323093

Pulled By: ajkr

fbshipit-source-id: 28d4106d0ca1740c3b896c755edf82d504b74801
2020-12-22 23:45:58 -08:00
Cheng Chang
70f2e0916a Write min_log_number_to_keep to MANIFEST during atomic flush under 2 phase commit (#7570)
Summary:
When 2 phase commit is enabled, if there are prepared data in a WAL, the WAL should be kept, the minimum log number for such a WAL is written to MANIFEST during flush. In atomic flush, such information is not written to MANIFEST.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7570

Test Plan: Added a new unit test `DBAtomicFlushTest.ManualFlushUnder2PC`, this test fails in atomic flush without this PR, after this PR, it succeeds.

Reviewed By: riversand963

Differential Revision: D24394222

Pulled By: cheng-chang

fbshipit-source-id: 60ce74b21b704804943be40c8de01b41269cf116
2020-12-03 19:22:24 -08:00
Cheng Chang
8c93b16f02 Track WAL in MANIFEST: Update logic for computing min_log_number_to_keep in atomic flush (#7660)
Summary:
The logic for computing min_log_number_to_keep in atomic flush was incorrect.

For example, when all column families are flushed, the min_log_number_to_keep should be the latest new log. But the incorrect logic calls `PrecomputeMinLogNumberToKeepNon2PC` for each column family, and returns the minimum of them. However, `PrecomputeMinLogNumberToKeepNon2PC(cf)` assumes column families other than `cf` are flushed, but in case all column families are flushed, this assumption is incorrect.

Without this fix, the WAL referenced by the computed min_log_number_to_keep may actually contain no unflushed data, so the WAL might have actually been deleted from disk on recovery, then an incorrect error `Corruption: missing WAL` will be reported.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7660

Test Plan:
run `make crash_test_with_atomic_flush`  on devserver
added a unit test in `db_flush_test`

Reviewed By: riversand963

Differential Revision: D24906265

Pulled By: cheng-chang

fbshipit-source-id: 08deda62e71f67f59e3b7925cdd86dd09bd4f430
2020-11-17 15:55:55 -08:00
Cheng Chang
5e794b0841 Fix a recovery corner case (#7621)
Summary:
Consider the following sequence of events:

1. Db flushed an SST with file number N, appended to MANIFEST, and tried to sync the MANIFEST.
2. Syncing MANIFEST failed and db crashed.
3. Db tried to recover with this MANIFEST. In the meantime, no entry about the newly-flushed SST was found in the MANIFEST. Therefore, RocksDB replayed WAL and tried to flush to an SST file reusing the same file number N. This failed because file system does not support overwrite. Then Db deleted this file.
4. Db crashed again.
5. Db tried to recover. When db read the MANIFEST, there was an entry referencing N.sst. This could happen probably because the append in step 1 finally reached the MANIFEST and became visible. Since N.sst had been deleted in step 3, recovery failed.

It is possible that N.sst created in step 1 is valid. Although step 3 would still fail since the MANIFEST was not synced properly in step 1 and 2, deleting N.sst would make it impossible for the db to recover even if the remaining part of MANIFEST was appended and visible after step 5.

After this PR, in step 3, immediately after recovering from MANIFEST, a new MANIFEST is created, then we find that N.sst is not referenced in the MANIFEST, so we delete it, and we'll not reuse N as file number. Then in step 5, since the new MANIFEST does not contain N.sst, the recovery failure situation in step 5 won't happen.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7621

Test Plan:
1. some tests are updated, because these tests assume that new MANIFEST is created after WAL recovery.
2. a new unit test is added in db_basic_test to simulate step 3.

Reviewed By: riversand963

Differential Revision: D24668144

Pulled By: cheng-chang

fbshipit-source-id: 90d7487fbad2bc3714f5ede46ea949895b15ae3b
2020-11-07 22:23:27 -08:00
Cheng Chang
1e40696dd1 Track WAL in MANIFEST: LogAndApply WAL events to MANIFEST (#7601)
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
2020-11-06 17:22:36 -08:00
Zhichao Cao
d8ec0a760a Make FileType Public and Replace kLogFile with kWalFile (#7580)
Summary:
As suggested by pdillinger ,The name of kLogFile is misleading, in some tests, kLogFile is defined as info log. Replace it with kWalFile and move it to public, which will be used in https://github.com/facebook/rocksdb/issues/7523

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7580

Test Plan: make check

Reviewed By: riversand963

Differential Revision: D24485420

Pulled By: zhichao-cao

fbshipit-source-id: 955e3dacc1021bb590fde93b0a568ffe9ad80799
2020-10-22 17:06:20 -07:00
Yanqin Jin
07dc955a1f Report error of GetChildren (#7459)
Summary:
As title

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7459

Test Plan: make check

Reviewed By: anand1976

Differential Revision: D23999393

Pulled By: riversand963

fbshipit-source-id: 09df8e1637f4df3616c63ee314de397b35be4e4a
2020-09-29 15:27:00 -07:00
sdong
d08a9005b7 Make db_basic_test pass assert status checked (#7452)
Summary:
Add db_basic_test status check list. Some of the warnings are suppressed. It is possible that some of them are due to real bugs.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7452

Test Plan: See CI tests pass.

Reviewed By: zhichao-cao

Differential Revision: D23979764

fbshipit-source-id: 6151570c2a9b931b0fbb3fe939a94b2bd1583cbe
2020-09-29 09:49:04 -07:00
Peter Dillinger
c8a12aa94b EnableFileDeletions only read field while holding mutex (#7435)
Summary:
Possible fix for a TSAN issue reported in EnableFileDeletions.
disable_delete_obsolete_files_ should only be accessed holding the db
mutex, but for logging it was being accessed outside holding the mutex,
now fixed.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7435

Test Plan: existing tests, watch for recurrence

Reviewed By: ltamasi

Differential Revision: D23917578

Pulled By: pdillinger

fbshipit-source-id: 8573025bca3f6fe169b24b87bbfc4ce9667b0482
2020-09-25 13:34:36 -07:00
mrambacher
e9befdebbf Add EnvTestWithParam::OptionsTest to the ASSERT_STATUS_CHECKED passes (#7283)
Summary:
This test uses database functionality and required more extensive work to get it to pass than the other tests.  The DB functionality required for this test now passes the check.

When it was unclear what the proper behavior was for unchecked status codes, a TODO was added.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7283

Reviewed By: akankshamahajan15

Differential Revision: D23251497

Pulled By: ajkr

fbshipit-source-id: 52b79629bdafa0a58de8ead1d1d66f141b331523
2020-08-20 19:18:35 -07:00
mrambacher
d9d190742c Make env*_test work with ASSERT_STATUS_CHECKED (#7176)
Summary:
Make (most of) the env*_test pass when ASSERT_STATUS_CHECKED is enabled.

One test that opens a database is currently disabled in this mode, as there are many errors that need revisited for DB tests and status checks.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7176

Reviewed By: cheng-chang

Differential Revision: D22799278

Pulled By: ajkr

fbshipit-source-id: 16d8a02eaeecd6df1060249b6a5811292801f2ed
2020-07-28 22:59:48 -07:00
Yanqin Jin
e66199d848 First step towards handling MANIFEST write error (#6949)
Summary:
This PR provides preliminary support for handling IO error during MANIFEST write.
File write/sync is not guaranteed to be atomic. If we encounter an IOError while writing/syncing to the MANIFEST file, we cannot be sure about the state of the MANIFEST file. The version edits may or may not have reached the file. During cleanup, if we delete the newly-generated SST files referenced by the pending version edit(s), but the version edit(s) actually are persistent in the MANIFEST, then next recovery attempt will process the version edits(s) and then fail since the SST files have already been deleted.
One approach is to truncate the MANIFEST after write/sync error, so that it is safe to delete the SST files. However, file truncation may not be supported on certain file systems. Therefore, we take the following approach.
If an IOError is detected during MANIFEST write/sync, we disable file deletions for the faulty database. Depending on whether the IOError is retryable (set by underlying file system), either RocksDB or application can call `DB::Resume()`, or simply shutdown and restart. During `Resume()`, RocksDB will try to switch to a new MANIFEST and write all existing in-memory version storage in the new file. If this succeeds, then RocksDB may proceed. If all recovery is completed, then file deletions will be re-enabled.
Note that multiple threads can call `LogAndApply()` at the same time, though only one of them will be going through the process MANIFEST write, possibly batching the version edits of other threads. When the leading MANIFEST writer finishes, all of the MANIFEST writing threads in this batch will have the same IOError. They will all call `ErrorHandler::SetBGError()` in which file deletion will be disabled.

Possible future directions:
- Add an `ErrorContext` structure so that it is easier to pass more info to `ErrorHandler`. Currently, as in this example, a new `BackgroundErrorReason` has to be added.

Test plan (dev server):
make check
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6949

Reviewed By: anand1976

Differential Revision: D22026020

Pulled By: riversand963

fbshipit-source-id: f3c68a2ef45d9b505d0d625c7c5e0c88495b91c8
2020-06-24 19:07:08 -07:00
Yanqin Jin
e72e2167fd Fix a few bugs in best-efforts recovery (#6824)
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
2020-05-08 13:01:42 -07:00
Levi Tamasi
ac3ae1df0b Find/purge obsolete blob files (#6807)
Summary:
The patch extends `FindObsoleteFiles` and `PurgeObsoleteFiles` with
support for blob files. The behavior is analogous to SST files: obsolete
blob files are put on the "candidates for deletion" list, while live (and pending)
files are preserved.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6807

Test Plan: `make check`

Reviewed By: riversand963

Differential Revision: D21406249

Pulled By: ltamasi

fbshipit-source-id: 1948f71c31927564b61e8af394f50ca3964880d9
2020-05-07 09:32:51 -07:00
Levi Tamasi
a00ddf1574 Expose the set of live blob files from Version/VersionSet (#6785)
Summary:
The patch adds logic that returns the set of live blob files from
`Version::AddLiveFiles` and `VersionSet::AddLiveFiles` (in addition to
live table files), and also cleans up the code a bit, for example, by
exposing only the numbers of table files as opposed to the earlier
`FileDescriptor`s that no clients used. Moreover, the patch extends
the `GetLiveFiles` API so that it also exposes blob files in the current version.
Similarly to https://github.com/facebook/rocksdb/pull/6755,
this is a building block for identifying and purging obsolete blob files.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6785

Test Plan: `make check`

Reviewed By: riversand963

Differential Revision: D21336210

Pulled By: ltamasi

fbshipit-source-id: fc1aede8a49eacd03caafbc5f6f9ce43b6270821
2020-05-04 15:08:13 -07:00
Levi Tamasi
fe238e5438 Keep track of obsolete blob files in VersionSet (#6755)
Summary:
The patch adds logic to keep track of obsolete blob files. A blob file becomes
obsolete when the last `shared_ptr` that points to the corresponding
`SharedBlobFileMetaData` object goes away, which, in turn, happens when the
last `Version` that contains the blob file is destroyed. No longer needed blob
files are added to the obsolete list in `VersionSet` using a custom deleter to
avoid unnecessary coupling between `SharedBlobFileMetaData` and `VersionSet`.
Obsolete blob files are returned by `VersionSet::GetObsoleteFiles` and stored
in `JobContext`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6755

Test Plan: `make check`

Reviewed By: riversand963

Differential Revision: D21233155

Pulled By: ltamasi

fbshipit-source-id: 47757e06fdc0127f27ed57f51abd27893d9a7b7a
2020-04-30 11:25:51 -07:00
Yanqin Jin
e04f3bce4f Update CURRENT file after best-efforts recovery (#6746)
Summary:
After a successful recovery, the CURRENT file should be updated to point to the valid MANIFEST.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6746

Test Plan: make check

Reviewed By: anand1976

Differential Revision: D21189876

Pulled By: riversand963

fbshipit-source-id: 7537b49988c5c425ebe9505a5cc260de351ad79b
2020-04-23 16:21:09 -07:00
Yanqin Jin
fb09ef05dc Attempt to recover from db with missing table files (#6334)
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
2020-03-20 19:30:48 -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
Levi Tamasi
752c87af78 Clean up VersionEdit a bit (#6383)
Summary:
This is a bunch of small improvements to `VersionEdit`. Namely, the patch

* Makes the names and order of variables, methods, and code chunks related
  to the various information elements more consistent, and adds missing
  getters for the sake of completeness.
* Initializes previously uninitialized stack variables.
* Marks all getters const to improve const correctness.
* Adds in-class initializers and removes the default ctor that would
  create an object with uninitialized built-in fields and call `Clear`
  afterwards.
* Adds a new type alias for new files and changes the existing `typedef`
  for deleted files into a type alias as well.
* Makes the helper method `DecodeNewFile4From` private.
* Switches from long-winded iterator syntax to range based loops in a
  couple of places.
* Fixes a couple of assignments where an integer 0 was assigned to
  boolean members.
* Fixes a getter which used to return a `const std::string` instead of
the intended `const std::string&`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6383

Test Plan: make check

Differential Revision: D19780537

Pulled By: ltamasi

fbshipit-source-id: b0b4f09fee0ec0e7c7b7a6d76bfe5346e91824d0
2020-02-07 13:27:06 -08:00
Yanqin Jin
fe1147db1c Let DBSecondary close files after catch up (#6114)
Summary:
After secondary instance replays the logs from primary, certain files become
obsolete. The secondary should find these files, evict their table readers from
table cache and close them. If this is not done, the secondary will hold on to
these files and prevent their space from being freed.

Test plan (devserver):
```
$./db_secondary_test --gtest_filter=DBSecondaryTest.SecondaryCloseFiles
$make check
$./db_stress -ops_per_thread=100000 -enable_secondary=true -threads=32 -secondary_catch_up_one_in=10000 -clear_column_family_one_in=1000 -reopen=100
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6114

Differential Revision: D18769998

Pulled By: riversand963

fbshipit-source-id: 5d1f151567247196164e1b79d8402fa2045b9120
2019-12-02 17:45:03 -08:00
Yanqin Jin
6d072f2a03 Move WAL-closing loop out of original loop (#5804)
Summary:
Originally the loop of closing WAL in PurgeObsoleteFiles resides inside a loop
iterating over the candidate files. It should be moved out.

Test plan (devserver)
```
$COMPILE_WITH_ASAN=1 make -j32 all
$make check
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5804

Differential Revision: D17374350

Pulled By: riversand963

fbshipit-source-id: 2bee7343fc0481d9a385a87c7676491522285c96
2019-09-17 17:17:19 -07:00
Yi Wu
a68d814570 fast look up purge_queue (#5796)
Summary:
purge_queue_ maybe contains thousands sst files, for example manual compact a range. If full scan is triggered at the same time and the total sst files number is large, RocksDB will be blocked at https://github.com/facebook/rocksdb/blob/master/db/db_impl_files.cc#L150 for several seconds. In our environment we have 140,000 sst files and the manual compaction delete about 1000 sst files, it blocked about 2 minutes.

Commandeering https://github.com/facebook/rocksdb/issues/5290.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5796

Differential Revision: D17357775

Pulled By: riversand963

fbshipit-source-id: 20eacca917355b8de975ccc7b1c9a3e7bd5b201a
2019-09-17 16:47:55 -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
Zhongyi Xie
d1c9ede195 Fix duplicated file names in PurgeObsoleteFiles (#5603)
Summary:
Currently in `DBImpl::PurgeObsoleteFiles`, the list of candidate files is create through a combination of calling LogFileName using `log_delete_files` and `full_scan_candidate_files`.

In full_scan_candidate_files, the filenames look like this
{file_name = "074715.log", file_path = "/txlogs/3306"},
but LogFileName produces filenames like this that prepends a slash:
{file_name = "/074715.log", file_path = "/txlogs/3306"},

This confuses the dedup step here: bb4178066d/db/db_impl/db_impl_files.cc (L339-L345)

Because duplicates still exist, DeleteFile is called on the same file twice, and hits an error on the second try. Error message: Failed to mark /txlogs/3302/764418.log as trash.

The root cause is the use of `kDumbDbName` when generating file names, it creates file names like /074715.log. This PR removes the use of `kDumbDbName` and create paths without leading '/' when dbname can be ignored.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5603

Test Plan: make check

Differential Revision: D16413203

Pulled By: miasantreble

fbshipit-source-id: 6ba8288382c55f7d5e3892d722fc94b57d2e4491
2019-08-01 15:50:05 -07:00
anand76
e0d9d57750 Fix bugs in WAL trash file handling (#5520)
Summary:
1. Cleanup WAL trash files on open
2. Don't apply deletion rate limit if WAL dir is different from db dir
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5520

Test Plan: Add new unit tests and make check

Differential Revision: D16096750

Pulled By: anand1976

fbshipit-source-id: 6f07858ad864b754b711db416f0389c45ede599b
2019-07-06 21:07:32 -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