Commit Graph

2 Commits

Author SHA1 Message Date
Andrew Kryczka
a6a6aad74e db_stress support tracking historical values (#8960)
Summary:
When `--sync_fault_injection` is set, this PR takes a snapshot of the expected values and starts an operation trace when the DB is opened. These files are stored in `--expected_values_dir`. They will be used for recovering the expected state of the DB following a crash where a suffix of unsynced operations are allowed to be lost.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8960

Test Plan: injected crashed at various points in `FileExpectedStateManager` and verified the next run recovers the state/trace file with highest seqno and removes all older/temporary files. Note we don't use sync_fault_injection in CI crash tests yet.

Reviewed By: pdillinger

Differential Revision: D31194941

Pulled By: ajkr

fbshipit-source-id: b0f935a529a0186c5a9c7709fcaa8829de8a84cf
2021-12-07 13:41:48 -08:00
Andrew Kryczka
559943cdc0 Refactor expected state in stress/crash test (#8913)
Summary:
This is a precursor refactoring to enable an upcoming feature: persistence failure correctness testing.

- Changed `--expected_values_path` to `--expected_values_dir` and migrated "db_crashtest.py" to use the new flag. For persistence failure correctness testing there are multiple possible correct states since unsynced data is allowed to be dropped. Making it possible to restore all these possible correct states will eventually involve files containing snapshots of expected values and DB trace files.
- The expected values directory is managed by an `ExpectedStateManager` instance. Managing expected state files is separated out of `SharedState` to prevent `SharedState` from becoming too complex when the new files and features (snapshotting, tracing, and restoring) are introduced.
- Migrated expected values file access/management out of `SharedState` into a separate class called `ExpectedState`. This is not exposed directly to the test but rather the `ExpectedState` for the latest values file is accessed via a pass-through API on `ExpectedStateManager`. This forces the test to always access the single latest `ExpectedState`.
- Changed the initialization of the latest expected values file to use a tempfile followed by rename, and also add cleanup logic for possible stranded tempfiles.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8913

Test Plan:
run in several ways; try to make sure it's not obviously broken.

- crashtest blackbox without TEST_TMPDIR
```
$ python3 tools/db_crashtest.py blackbox --simple --write_buffer_size=1048576 --target_file_size_base=1048576 --max_bytes_for_level_base=4194304 --max_key=100000 --value_size_mult=33 --compression_type=none --duration=120 --interval=10 --compression_type=none --blob_compression_type=none
```
- crashtest blackbox with TEST_TMPDIR
```
$ TEST_TMPDIR=/dev/shm python3 tools/db_crashtest.py blackbox --simple --write_buffer_size=1048576 --target_file_size_base=1048576 --max_bytes_for_level_base=4194304 --max_key=100000 --value_size_mult=33 --compression_type=none --duration=120 --interval=10 --compression_type=none --blob_compression_type=none
```
- crashtest whitebox with TEST_TMPDIR
```
$ TEST_TMPDIR=/dev/shm python3 tools/db_crashtest.py whitebox --simple --write_buffer_size=1048576 --target_file_size_base=1048576 --max_bytes_for_level_base=4194304 --max_key=100000 --value_size_mult=33 --compression_type=none --duration=120 --interval=10 --compression_type=none --blob_compression_type=none --random_kill_odd=88887
```
- db_stress without expected_values_dir
```
$ ./db_stress --write_buffer_size=1048576 --target_file_size_base=1048576 --max_bytes_for_level_base=4194304 --max_key=100000 --value_size_mult=33 --compression_type=none --ops_per_thread=10000 --clear_column_family_one_in=0 --destroy_db_initially=true
```
- db_stress with expected_values_dir and manual corruption
```
$ ./db_stress --write_buffer_size=1048576 --target_file_size_base=1048576 --max_bytes_for_level_base=4194304 --max_key=100000 --value_size_mult=33 --compression_type=none --ops_per_thread=10000 --clear_column_family_one_in=0 --destroy_db_initially=true --expected_values_dir=./
// modify one byte in "./LATEST.state"
$ ./db_stress --write_buffer_size=1048576 --target_file_size_base=1048576 --max_bytes_for_level_base=4194304 --max_key=100000 --value_size_mult=33 --compression_type=none --ops_per_thread=10000 --clear_column_family_one_in=0 --destroy_db_initially=false --expected_values_dir=./
...
Verification failed for column family 0 key 0000000000000000 (0): Value not found: NotFound:
...
```

Reviewed By: riversand963

Differential Revision: D30921951

Pulled By: ajkr

fbshipit-source-id: babfe218062e55d018c9b046536c0289fb78f41c
2021-09-28 14:13:33 -07:00