Summary:
As mentioned in https://github.com/facebook/rocksdb/pull/5506#issuecomment-506021913,
`db_stress` does not have much verification for iterator correctness.
It has a `TestIterate()` function, but that is mainly for comparing results
between two iterators, one with `total_order_seek` and the other optionally
sets auto_prefix, upper/lower bounds. Commit 49a0581ad2462e31aa3f768afa769e0d33390f33
added a new `TestIterateAgainstExpected()` function that compares iterator against
expected state. It locks a range of keys, creates an iterator, does
a random sequence of `Next/Prev` and compares against expected state.
This PR is based on that commit, the main changes include some logs
(for easier debugging if a test fails), a forward and backward scan to
cover the entire locked key range, and a flag for optionally turning on
this version of Iterator testing.
Added constraint that the checks against expected state in
`TestIterateAgainstExpected()` and in `TestGet()` are only turned on
when `--skip_verifydb` flag is not set.
Remove the change log introduced in https://github.com/facebook/rocksdb/issues/10553.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10538
Test Plan:
Run `db_stress` with `--verify_iterator_with_expected_state_one_in=1`,
and a large `--iterpercent` and `--num_iterations`. Checked `op_logs`
manually to ensure expected coverage. Tweaked part of the code in
https://github.com/facebook/rocksdb/issues/10449 and stress test was able to catch it.
- internally run various flavor of crash test
Reviewed By: ajkr
Differential Revision: D38847269
Pulled By: cbi42
fbshipit-source-id: 8b4402a9bba9f6cfa08051943cd672579d489599
Changyu Bi