Summary:
Context:
OptimisticTransactionDB has not been covered by db_stress (including crash test) like TransactionDB.
1. Adding the following gflag options to to test OptimisticTransactionDB
- `use_optimistic_txn`: When true, open OptimisticTransactionDB to test
- `occ_validation_policy`: `OccValidationPolicy::kValidateParallel = 1` by default.
- `share_occ_lock_buckets`: Use shared occ locks
- `occ_lock_bucket_count`: 500 by default. Number of buckets to use for shared occ lock.
2. Opening OptimisticTransactionDB and NewTxn/Commit added per `use_optimistic_txn` flag in `db_stress_test_base.cc`
3. OptimisticTransactionDB blackbox/whitebox test added in crash_test.mk
Please note that the existing flag `use_txn` is being used here. When `use_txn == true` and `use_optimistic_txn == false`, we use `TransactionDB` (a.k.a. pessimistic transaction db). When both `use_txn` and `use_optimistic_txn` are true, we use `OptimisticTransactionDB`. If `use_txn == false` but `use_optimistic_txn == true` throw error with message _"You cannot set use_optimistic_txn true while use_txn is false. Please set use_txn true if you want to use OptimisticTransactionDB"_.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11513
Test Plan:
**Crash Test**
Serial Validation
```
export CRASH_TEST_EXT_ARGS="--use_optimistic_txn=1 --use_txn=1 --use_put_entity_one_in=0 --occ_validation_policy=0"
make crash_test -j
```
Parallel Validation (no share bucket)
```
export CRASH_TEST_EXT_ARGS="--use_optimistic_txn=1 --use_txn=1 --use_put_entity_one_in=0 --occ_validation_policy=1 --share_occ_lock_buckets=0"
make crash_test -j
```
Parallel Validation (share bucket)
```
export CRASH_TEST_EXT_ARGS="--use_optimistic_txn=1 --use_txn=1 --use_put_entity_one_in=0 --occ_validation_policy=1 --share_occ_lock_buckets=1 --occ_lock_bucket_count=500"
make crash_test -j
```
**Stress Test**
```
./db_stress -use_optimistic_txn -threads=32
```
Reviewed By: pdillinger
Differential Revision: D46547387
Pulled By: jaykorean
fbshipit-source-id: ca19819ca6e0281694966998014b40d95d4e5960
print("`compaction_style` is changed in current run so `destroy_db_initially` is set to 1 as a short-term solution to avoid cycling through previous db of different compaction style."+"\n")
"`compaction_style` is changed in current run so `destroy_db_initially` is set to 1 as a short-term solution to avoid cycling through previous db of different compaction style."