Summary:
This fixes two bugs in the recently committed DB verification following
crash-recovery with unsynced data loss (https://github.com/facebook/rocksdb/issues/8966):
The first bug was in crash test runs involving mixed values for
`-test_batches_snapshots`. The problem was we were neither restoring
expected values nor enabling tracing when `-test_batches_snapshots=1`.
This caused a future `-test_batches_snapshots=0` run to not find enough
trace data to restore expected values. The fix is to restore expected
values at the start of `-test_batches_snapshots=1` runs, but still leave
tracing disabled as we do not need to track those KVs.
The second bug was in `db_stress` runs that restore the expected values
file and use compaction filter. The compaction filter was initialized to use
the pre-restore expected values, which would be `munmap()`'d during
`FileExpectedStateManager::Restore()`. Then compaction filter would run
into a segfault. The fix is just to reorder compaction filter init after expected
values restore.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9302
Test Plan:
- To verify the first problem, the below sequence used to fail; now it passes.
```
$ ./db_stress --db=./test-db/ --expected_values_dir=./test-db-expected/ --max_key=100000 --ops_per_thread=1000 --sync_fault_injection=1 --clear_column_family_one_in=0 --destroy_db_initially=0 -reopen=0 -test_batches_snapshots=0
$ ./db_stress --db=./test-db/ --expected_values_dir=./test-db-expected/ --max_key=100000 --ops_per_thread=1000 --sync_fault_injection=1 --clear_column_family_one_in=0 --destroy_db_initially=0 -reopen=0 -test_batches_snapshots=1
$ ./db_stress --db=./test-db/ --expected_values_dir=./test-db-expected/ --max_key=100000 --ops_per_thread=1000 --sync_fault_injection=1 --clear_column_family_one_in=0 --destroy_db_initially=0 -reopen=0 -test_batches_snapshots=0
```
- The second problem occurred rarely in the form of a SIGSEGV on a file that was `munmap()`d. I have not seen it after this PR though this doesn't prove much.
Reviewed By: jay-zhuang
Differential Revision: D33155283
Pulled By: ajkr
fbshipit-source-id: 66fd0f0edf34015a010c30015f14f104734e964e
863c78d2c9