Summary:
When the `iter_start_ts` read option is set, iterator exposes internal keys. This also includes tombstones, which by definition do not have a value (or columns). The patch makes sure we skip the wide-column consistency check in this case.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10799
Test Plan: Tested using a simple blackbox crash test with timestamps enabled.
Reviewed By: jay-zhuang, riversand963
Differential Revision: D40235628
fbshipit-source-id: 49519fb55d8fe2bb9249ced809f7a81bff2b9df2
Summary:
The patch adds checks to the
`{NonBatchedOps,BatchedOps,CfConsistency}StressTest::TestPrefixScan` methods
to make sure the wide columns exposed by the iterators are as expected (based on
the value base encoded into the iterator value). It also makes some code hygiene
improvements in these methods.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10786
Test Plan:
Ran some simple blackbox tests in the various modes (non-batched, batched,
CF consistency).
Reviewed By: riversand963
Differential Revision: D40163623
Pulled By: riversand963
fbshipit-source-id: 72f4c3b51063e48c15f974c4ec64d751d3ed0a83
Summary:
As the first step of covering the wide-column functionality of iterators
in our stress tests, the patch adds verification logic to
`NonBatchedOpsStressTest::VerifyDb` that checks whether the
iterator's value and columns are in sync. Note: I plan to update the other
types of stress tests and add similar verification for prefix scans etc.
in separate PRs.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10783
Test Plan: Ran some simple blackbox crash tests.
Reviewed By: riversand963
Differential Revision: D40152370
Pulled By: riversand963
fbshipit-source-id: 8f9d17d7af5da58ccf1bd2057cab53cc9645ac35
Summary:
We have seen some rare crash test failures in HyperClockCache, and the source could certainly be a bug fixed in this change, in ClockHandleTable::ConstApplyToEntriesRange. It wasn't properly accounting for the fact that incrementing the acquire counter could be ineffective, due to parallel updates. (When incrementing the acquire counter is ineffective, it is incorrect to then decrement it.)
This change includes some other minor clean-up in HyperClockCache, and adds stats_dump_period_sec with a much lower period to the crash test. This should be the primary caller of ApplyToEntries, in collecting cache entry stats.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10768
Test Plan: haven't been able to reproduce the failure, but should be in a better state (bug fix and improved crash test)
Reviewed By: anand1976
Differential Revision: D40034747
Pulled By: anand1976
fbshipit-source-id: a06fcefe146e17ee35001984445cedcf3b63eb68
Summary:
`SstFileWriter` currently does not support the `PutEntity` API, so in `TestIngestExternalFile` all key-values are written using regular `Put`s. This violates the assumption that whether or not a key corresponds to a plain old key-value or a wide-column entity can be determined by solely looking at the "value base" used when generating the value. The patch fixes this issue by disabling ingestion when `PutEntity` is enabled in the stress tests.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10769
Test Plan: Ran a simple blackbox stress test.
Reviewed By: akankshamahajan15
Differential Revision: D40042132
Pulled By: ltamasi
fbshipit-source-id: 93e75ff55545b7b69fa4ddef1d96093c961158a0
Summary:
added calls to `Iterator::Refresh()` in `NonBatchedOpsStressTest::TestIterateAgainstExpected()`. The testing key range is locked in `TestIterateAgainstExpected` so I do not expect this change to provide thorough stress test to `Iterator::Refresh()`. However, it can still be helpful for catching bugs like https://github.com/facebook/rocksdb/issues/10739. Will add calls to refresh in `TestIterate` once we support iterator refresh with snapshots.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10766
Test Plan: `python3 tools/db_crashtest.py whitebox --simple --verify_iterator_with_expected_state_one_in=2`
Reviewed By: ajkr
Differential Revision: D40008320
Pulled By: ajkr
fbshipit-source-id: cec93b07f915ef6476d41c1fee9b23c115188085
Summary:
Add user-defined timestamp support for range deletion. The new API is `DeleteRange(opt, cf, begin_key, end_key, ts)`. Most of the change is to update the comparator to compare without timestamp. Other than that, major changes are
- internal range tombstone data structures (`FragmentedRangeTombstoneList`, `RangeTombstone`, etc.) to store timestamps.
- Garbage collection of range tombstones and range tombstone covered keys during compaction.
- Get()/MultiGet() to return the timestamp of a range tombstone when needed.
- Get/Iterator with range tombstones bounded by readoptions.timestamp.
- timestamp crash test now issues DeleteRange by default.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10661
Test Plan:
- Added unit test: `make check`
- Stress test: `python3 tools/db_crashtest.py --enable_ts whitebox --readpercent=57 --prefixpercent=4 --writepercent=25 -delpercent=5 --iterpercent=5 --delrangepercent=4`
- Ran `db_bench` to measure regression when timestamp is not enabled. The tests are for write (with some range deletion) and iterate with DB fitting in memory: `./db_bench--benchmarks=fillrandom,seekrandom --writes_per_range_tombstone=200 --max_write_buffer_number=100 --min_write_buffer_number_to_merge=100 --writes=500000 --reads=500000 --seek_nexts=10 --disable_auto_compactions -disable_wal=true --max_num_range_tombstones=1000`. Did not see consistent regression in no timestamp case.
| micros/op | fillrandom | seekrandom |
| --- | --- | --- |
|main| 2.58 |10.96|
|PR 10661| 2.68 |10.63|
Reviewed By: riversand963
Differential Revision: D39441192
Pulled By: cbi42
fbshipit-source-id: f05aca3c41605caf110daf0ff405919f300ddec2
Summary:
**Context/Summary:**
Introduce `manual_wal_flush_one_in` as titled.
- When `manual_wal_flush_one_in > 0`, we also need tracing to correctly verify recovery because WAL data can be lost in this case when `FlushWAL()` is not explicitly called by users of RocksDB (in our case, db stress) and the recovery from such potential WAL data loss is a prefix recovery that requires tracing to verify. As another consequence, we need to disable features can't run under unsync data loss with `manual_wal_flush_one_in`
Incompatibilities fixed along the way:
```
db_stress: db/db_impl/db_impl_open.cc:2063: static rocksdb::Status rocksdb::DBImpl::Open(const rocksdb::DBOptions&, const string&, const std::vector<rocksdb::ColumnFamilyDescriptor>&, std::vector<rocksdb::ColumnFamilyHandle*>*, rocksdb::DB**, bool, bool): Assertion `impl->TEST_WALBufferIsEmpty()' failed.
```
- It turns out that `Writer::AddCompressionTypeRecord` before this assertion `EmitPhysicalRecord(kSetCompressionType, encode.data(), encode.size());` but do not trigger flush if `manual_wal_flush` is set . This leads to `impl->TEST_WALBufferIsEmpty()' is false.
- As suggested, assertion is removed and violation case is handled by `FlushWAL(sync=true)` along with refactoring `TEST_WALBufferIsEmpty()` to be `WALBufferIsEmpty()` since it is used in prod code now.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10698
Test Plan:
- Locally running `python3 tools/db_crashtest.py blackbox --manual_wal_flush_one_in=1 --manual_wal_flush=1 --sync_wal_one_in=100 --atomic_flush=1 --flush_one_in=100 --column_families=3`
- Joined https://github.com/facebook/rocksdb/pull/10624 in auto CI testings with all RocksDB stress/crash test jobs
Reviewed By: ajkr
Differential Revision: D39593752
Pulled By: ajkr
fbshipit-source-id: 3a2135bb792c52d2ffa60257d4fbc557fb04d2ce
Summary:
If the `-expected_values_dir` argument to db_stress is empty, then verification against expected state is effectively disabled. But `RunStressTest` still calls `TrackExpectedState`, which returns `NotSupported` causing a the crash test to fail with a false alarm. Fix it by only calling `TrackExpectedState` if necessary.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10764
Reviewed By: ajkr
Differential Revision: D39980129
Pulled By: anand1976
fbshipit-source-id: d02651746fe3a297877a4b2b2fbcb7274860f49c
Summary:
The patch adds the `PutEntity` API to the non-batched, batched, and
CF consistency stress tests. Namely, when the new `db_stress` command
line parameter `use_put_entity_one_in` is greater than zero, one in
N writes on average is performed using `PutEntity` rather than `Put`.
The wide-column entity written has the generated value in its default
column; in addition, it contains up to three additional columns where
the original generated value is divided up between the column name and the
column value (with the column name containing the first k characters of
the generated value, and the column value containing the rest). Whether
`PutEntity` is used (and if so, how many columns the entity has) is completely
determined by the "value base" used to generate the value (that is, there is
no randomness involved). Assuming the same `use_put_entity_one_in` setting
is used across `db_stress` invocations, this enables us to reconstruct and
validate the entity during subsequent `db_stress` runs.
Note that `PutEntity` is currently incompatible with `Merge`, transactions, and
user-defined timestamps; these combinations are currently disabled/disallowed.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10760
Test Plan: Ran some batched, non-batched, and CF consistency stress tests using the script.
Reviewed By: riversand963
Differential Revision: D39939032
Pulled By: ltamasi
fbshipit-source-id: eafdf124e95993fb7d73158e3b006d11819f7fa9
Summary:
If all the keys in range [key_base, shared->GetMaxKey()) are non-overwritable `TestIngestExternalFile()` would attempt to ingest a file with zero keys, leading to the following error: "Cannot create sst file with no entries". This PR changes `TestIngestExternalFile()` to return early in that case instead of going through with the ingestion attempt.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10754
Reviewed By: hx235
Differential Revision: D39909195
Pulled By: ajkr
fbshipit-source-id: e06e6b9cc24826fbd450e5130885e6f07164badd
Summary:
An add-on to https://github.com/facebook/rocksdb/pull/6818 to complete adding single-level universal compaction to stress/crash testing.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10732
Test Plan:
- Locally run for 10 min `python3 ./tools/db_crashtest.py whitebox --simple --compaction_style=1 --num_levels=1 -max_key=1000000 -value_size_mult=33 -write_buffer_size=524288 -target_file_size_base=524288 -max_bytes_for_level_base=2097152 --duration=120 --interval=10 --ops_per_thread=1000 --random_kill_odd=887`
- Check LOG to confirm single-level universal compaction is called
- Manual testing and log checking to ensure destroy_db_initially=1 is correctly set across runs with different compaction styles (i.e, in the second half of whitebox testing).
- [ongoing]CI jobs stress test
Reviewed By: ajkr
Differential Revision: D39797612
Pulled By: ajkr
fbshipit-source-id: 16f5c40c3464c57360c06c8305f92118e426149c
Summary:
**Context:**
Prior to this PR, correctness testing with un-sync data loss [disabled](https://github.com/facebook/rocksdb/pull/10605) transaction (`use_txn=1`) thus all of the `txn_write_policy` . This PR improved that by adding support for one policy - WriteCommit (`txn_write_policy=0`).
**Summary:**
They key to this support is (a) handle Mark{Begin, End}Prepare/MarkCommit/MarkRollback in constructing ExpectedState under WriteCommit policy correctly and (b) monitor CI jobs and solve any test incompatibility issue till jobs are stable. (b) will be part of the test plan.
For (a)
- During prepare (i.e, between `MarkBeginPrepare()` and `MarkEndPrepare(xid)`), `ExpectedStateTraceRecordHandler` will buffer all writes by adding all writes to an internal `WriteBatch`.
- On `MarkEndPrepare()`, that `WriteBatch` will be associated with the transaction's `xid`.
- During the commit (i.e, on `MarkCommit(xid)`), `ExpectedStateTraceRecordHandler` will retrieve and iterate the internal `WriteBatch` and finally apply those writes to `ExpectedState`
- During the rollback (i.e, on `MarkRollback(xid)`), `ExpectedStateTraceRecordHandler` will erase the internal `WriteBatch` from the map.
For (b) - one major issue described below:
- TransactionsDB in db stress recovers prepared-but-not-committed txns from the previous crashed run by randomly committing or rolling back it at the start of the current run, see a historical [PR](6d06be22c0) predated correctness testing.
- And we will verify those processed keys in a recovered db against their expected state.
- However since now we turn on `sync_fault_injection=1` where the expected state is constructed from the trace instead of using the LATEST.state from previous run. The expected state now used to verify those processed keys won't contain UNKNOWN_SENTINEL as they should - see test 1 for a failed case.
- Therefore, we decided to manually update its expected state to be UNKNOWN_SENTINEL as part of the processing.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10624
Test Plan:
1. Test exposed the major issue described above. This test will fail without setting UNKNOWN_SENTINEL in expected state during the processing and pass after
```
db=/dev/shm/rocksdb_crashtest_blackbox
exp=/dev/shm/rocksdb_crashtest_expected
dbt=$db.tmp
expt=$exp.tmp
rm -rf $db $exp
mkdir -p $exp
echo "RUN 1"
./db_stress \
--clear_column_family_one_in=0 --column_families=1 --db=$db --delpercent=10 --delrangepercent=0 --destroy_db_initially=0 --expected_values_dir=$exp --iterpercent=0 --key_len_percent_dist=1,30,69 --max_key=1000000 --max_key_len=3 --prefixpercent=0 --readpercent=0 --reopen=0 --ops_per_thread=100000000 --test_batches_snapshots=0 --value_size_mult=32 --writepercent=90 \
--use_txn=1 --txn_write_policy=0 --sync_fault_injection=1 &
pid=$!
sleep 0.2
sleep 20
kill $pid
sleep 0.2
echo "RUN 2"
./db_stress \
--clear_column_family_one_in=0 --column_families=1 --db=$db --delpercent=10 --delrangepercent=0 --destroy_db_initially=0 --expected_values_dir=$exp --iterpercent=0 --key_len_percent_dist=1,30,69 --max_key=1000000 --max_key_len=3 --prefixpercent=0 --readpercent=0 --reopen=0 --ops_per_thread=100000000 --test_batches_snapshots=0 --value_size_mult=32 --writepercent=90 \
--use_txn=1 --txn_write_policy=0 --sync_fault_injection=1 &
pid=$!
sleep 0.2
sleep 20
kill $pid
sleep 0.2
echo "RUN 3"
./db_stress \
--clear_column_family_one_in=0 --column_families=1 --db=$db --delpercent=10 --delrangepercent=0 --destroy_db_initially=0 --expected_values_dir=$exp --iterpercent=0 --key_len_percent_dist=1,30,69 --max_key=1000000 --max_key_len=3 --prefixpercent=0 --readpercent=0 --reopen=0 --ops_per_thread=100000000 --test_batches_snapshots=0 --value_size_mult=32 --writepercent=90 \
--use_txn=1 --txn_write_policy=0 --sync_fault_injection=1
```
2. Manual testing to ensure ExpectedState is constructed correctly during recovery by verifying it against previously crashed TransactionDB's WAL.
- Run the following command to crash a TransactionDB with WriteCommit policy. Then `./ldb dump_wal` on its WAL file
```
db=/dev/shm/rocksdb_crashtest_blackbox
exp=/dev/shm/rocksdb_crashtest_expected
rm -rf $db $exp
mkdir -p $exp
./db_stress \
--clear_column_family_one_in=0 --column_families=1 --db=$db --delpercent=10 --delrangepercent=0 --destroy_db_initially=0 --expected_values_dir=$exp --iterpercent=0 --key_len_percent_dist=1,30,69 --max_key=1000000 --max_key_len=3 --prefixpercent=0 --readpercent=0 --reopen=0 --ops_per_thread=100000000 --test_batches_snapshots=0 --value_size_mult=32 --writepercent=90 \
--use_txn=1 --txn_write_policy=0 --sync_fault_injection=1 &
pid=$!
sleep 30
kill $pid
sleep 1
```
- Run the following command to verify recovery of the crashed db under debugger. Compare the step-wise result with WAL records (e.g, WriteBatch content, xid, prepare/commit/rollback marker)
```
./db_stress \
--clear_column_family_one_in=0 --column_families=1 --db=$db --delpercent=10 --delrangepercent=0 --destroy_db_initially=0 --expected_values_dir=$exp --iterpercent=0 --key_len_percent_dist=1,30,69 --max_key=1000000 --max_key_len=3 --prefixpercent=0 --readpercent=0 --reopen=0 --ops_per_thread=100000000 --test_batches_snapshots=0 --value_size_mult=32 --writepercent=90 \
--use_txn=1 --txn_write_policy=0 --sync_fault_injection=1
```
3. Automatic testing by triggering all RocksDB stress/crash test jobs for 3 rounds with no failure.
Reviewed By: ajkr, riversand963
Differential Revision: D39199373
Pulled By: hx235
fbshipit-source-id: 7a1dec0e3e2ee6ea86ddf5dd19ceb5543a3d6f0c
Summary:
The PR cleans up the logic in `NonBatchedOpsStressTest::VerifyDb` so that
the verification method is picked using a single random number generation.
It also eliminates some repeated key comparisons and makes some small
code hygiene improvements.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10740
Test Plan: Ran a simple blackbox crash test.
Reviewed By: riversand963
Differential Revision: D39828646
Pulled By: ltamasi
fbshipit-source-id: 60ee5a3bb1851278f62c7d83b0c93b902ed9702e
Summary:
This change establishes a distinctive name for the experimental new lock-free clock cache (originally developed by guidotag and revamped in PR https://github.com/facebook/rocksdb/issues/10626). A few reasons:
* We want to make it clear that this is a fundamentally different implementation vs. the old clock cache, to avoid people saying "I already tried clock cache."
* We want to highlight the key feature: it's fast (especially under parallel load)
* Because it requires an estimated charge per entry, it is not drop-in API compatible with old clock cache. This estimate might always be required for highest performance, and giving it a distinct name should reduce confusion about the distinct API requirements.
* We might develop a variant requiring the same estimate parameter but with LRU eviction. In that case, using the name HyperLRUCache should make things more clear. (FastLRUCache is just a prototype that might soon be removed.)
Some API detail:
* To reduce copy-pasting parameter lists, etc. as in LRUCache construction, I have a `MakeSharedCache()` function on `HyperClockCacheOptions` instead of `NewHyperClockCache()`.
* Changes -cache_type=clock_cache to -cache_type=hyper_clock_cache for applicable tools. I think this is more consistent / sustainable for reasons already stated.
For performance tests see https://github.com/facebook/rocksdb/pull/10626
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10684
Test Plan: no interesting functional changes; tests updated
Reviewed By: anand1976
Differential Revision: D39547800
Pulled By: pdillinger
fbshipit-source-id: 5c0fe1b5cf3cb680ab369b928c8569682b9795bf
Summary:
One problem of the previous strategy was `NonBatchedOpsStressTest::TestIngestExternalFile()` could release the lock for `rand_keys[0]` in `rand_column_families[0]`, and then subsequent operations in the same loop iteration (e.g., `TestPut()`) would run without locking. This PR changes the strategy so each `Test*()` function is responsible for acquiring and releasing its own locks.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10678
Reviewed By: hx235
Differential Revision: D39516401
Pulled By: ajkr
fbshipit-source-id: bf67f12ebbd293ba8c24fdf8754ff28737bcd758
Summary:
In `db_stress`, DB and expected state files containing changes leading up to a verification failure are often deleted, which makes debugging such failures difficult. On the DB side, flushed WAL files and compacted SST files are marked obsolete and then deleted. Without those files, we cannot pinpoint where a key that failed verification changed unexpectedly. On the expected state side, files for verifying prefix-recoverability in the presence of unsynced data loss are deleted before verification. These include a baseline state file containing the expected state at the time of the last successful verification, and a trace file containing all operations since then. Without those files, we cannot know the sequence of DB operations expected to be recovered.
This PR attempts to address this gap with a new `db_stress` flag: `preserve_unverified_changes`. Setting `preserve_unverified_changes=1` has two effects.
First, prior to startup verification, `db_stress` hardlinks all DB and expected state files in "unverified/" subdirectories of `FLAGS_db` and `FLAGS_expected_values_dir`. The separate directories are needed because the pre-verification opening process deletes files written by the previous `db_stress` run as described above. These "unverified/" subdirectories are cleaned up following startup verification success.
I considered other approaches for preserving DB files through startup verification, like using a read-only DB or preventing deletion of DB files externally, e.g., in the `Env` layer. However, I decided against it since such an approach would not work for expected state files, and I did not want to change the DB management logic. If there were a way to disable DB file deletions before regular DB open, I would have preferred to use that.
Second, `db_stress` attempts to keep all DB and expected state files that were live at some point since the start of the `db_stress` run. This is a bit tricky and involves the following changes.
- Open the DB with `disable_auto_compactions=1` and `avoid_flush_during_recovery=1`
- DisableFileDeletions()
- EnableAutoCompactions()
For this part, too, I would have preferred to use a hypothetical API that disables DB file deletion before regular DB open.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10659
Reviewed By: hx235
Differential Revision: D39407454
Pulled By: ajkr
fbshipit-source-id: 6e981025c7dce147649d2e770728471395a7fa53
Summary:
Same as title
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10632
Test Plan: make crash_test -j32
Reviewed By: anand1976
Differential Revision: D39241479
Pulled By: akankshamahajan15
fbshipit-source-id: 5db5b0c007da786bacc1b30d8926d36d6d029b87
Summary:
Currently, `db_bench` and `db_stress` print the blob cache options even if
a shared block/blob cache is configured, i.e. when they are not actually
in effect. The patch changes this so they are only printed when a separate blob
cache is used.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10614
Test Plan: Tested manually using `db_bench` and `db_stress`.
Reviewed By: akankshamahajan15
Differential Revision: D39144603
Pulled By: ltamasi
fbshipit-source-id: f714304c5d46186f8514746c27ee6f52aa3e4af8
Summary:
When verification fails for db_stress, print more information about
value read from the db and expected state.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10587
Test Plan:
make check
./db_stress
Reviewed By: akankshamahajan15, hx235
Differential Revision: D39078511
Pulled By: riversand963
fbshipit-source-id: 77ac8ffae01fc3a9b58a02c2e7bbe141e1a18f0b
Summary:
https://github.com/facebook/rocksdb/issues/10538 added `TestIterateAgainstExpected()` in `no_batched_ops_test` to verify iterator correctness against the in memory expected state. It is not compatible when run after some other stress tests, e.g. `TestPut()` in `batched_op_stress`, that either do not set expected state when writing to DB or use keys that cannot be parsed by `GetIntVal()`. The assert [here](d17be55aab/db_stress_tool/db_stress_common.h (L520)) could fail. This PR fixed this issue by setting iterator upperbound to `max_key` when `destroy_db_initially=0` to avoid the key space that `batched_op_stress` touches.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10590
Test Plan:
```
# set up DB with batched_op_stress
./db_stress --test_batches_snapshots=1 --verify_iterator_with_expected_state_one_in=1 --max_key_len=3 --max_key=100000000 --skip_verifydb=1 --continuous_verification_interval=0 --writepercent=85 --delpercent=3 --delrangepercent=0 --iterpercent=10 --nooverwritepercent=1 --prefixpercent=0 --readpercent=2 --key_len_percent_dist=1,30,69
# Before this PR, the following test will fail the asserts with error msg like the following
# Assertion failed: (size_key <= key_gen_ctx.weights.size() * sizeof(uint64_t)), function GetIntVal, file db_stress_common.h, line 524.
./db_stress --verify_iterator_with_expected_state_one_in=1 --max_key_len=3 --max_key=100000000 --skip_verifydb=1 --continuous_verification_interval=0 --writepercent=0 --delpercent=3 --delrangepercent=0 --iterpercent=95 --nooverwritepercent=1 --prefixpercent=0 --readpercent=2 --key_len_percent_dist=1,30,69 --destroy_db_initially=0
```
Reviewed By: ajkr
Differential Revision: D39085243
Pulled By: cbi42
fbshipit-source-id: a7dfee2320c330773b623b442d730fd014ec7056
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
Summary:
updated `TestGet()` in `no_batched_op_stress` to check the result of `Get()` operations against expected state (`expected_state_manager_`). More specifically, if `Get()` finds a key, expected state should not have `DELETION_SENTINEL` for the same key, and if `Get()` returns NotFound for a key, expected state should not have the key. One intention for this change it to verify correctness of code path change regarding range tombstones.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10553
Test Plan: run db_stress with nonzero readpercent: `./db_stress_branch --readpercent=57 --prefixpercent=4 --writepercent=25 -delpercent=5 --iterpercent=5 --delrangepercent=4`. When I initially used wrong column family in `thread->shared->Get`, the test reported inconsistencies.
Reviewed By: ajkr
Differential Revision: D38927007
Pulled By: cbi42
fbshipit-source-id: f9f61b312ad0b4c21a799329609ba8526169b048
Summary:
To help service owners to manage their memory budget effectively, we have been working towards counting all major memory users inside RocksDB towards a single global memory limit (see e.g. https://github.com/facebook/rocksdb/wiki/Write-Buffer-Manager#cost-memory-used-in-memtable-to-block-cache). The global limit is specified by the capacity of the block-based table's block cache, and is technically implemented by inserting dummy entries ("reservations") into the block cache. The goal of this task is to support charging the memory usage of the new blob cache against this global memory limit when the backing cache of the blob cache and the block cache are different.
This PR is a part of https://github.com/facebook/rocksdb/issues/10156
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10321
Reviewed By: ltamasi
Differential Revision: D37913590
Pulled By: gangliao
fbshipit-source-id: eaacf23907f82dc7d18964a3f24d7039a2937a72
Summary:
Many workloads have temporal locality, where recently written items are read back in a short period of time. When using remote file systems, this is inefficient since it involves network traffic and higher latencies. Because of this, we would like to support prepopulating the blob cache during flush.
This task is a part of https://github.com/facebook/rocksdb/issues/10156
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10298
Reviewed By: ltamasi
Differential Revision: D37908743
Pulled By: gangliao
fbshipit-source-id: 9feaed234bc719d38f0c02975c1ad19fa4bb37d1
Summary:
This complements https://github.com/facebook/rocksdb/issues/10351. This PR reverts NewClockCache's signature to an older version, expected by the users of the old (buggy) ClockCache.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10358
Test Plan: ``make -j24 check`` and re-run the pre-release tests.
Reviewed By: siying
Differential Revision: D37832601
Pulled By: guidotag
fbshipit-source-id: 32a91d3da4119be187935003b7b897272ceb1950
Summary:
Before this PR, we call `now()` to get the wall time before performing point-lookup and range
scans when user-defined timestamp is enabled.
With this PR, we expand the coverage to:
- read with an older timestamp which is larger then the wall time when the process starts but potentially smaller than now()
- add coverage for `ReadOptions::iter_start_ts != nullptr`
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10280
Test Plan:
```bash
make check
```
Also,
```bash
TEST_TMPDIR=/dev/shm/rocksdb make crash_test_with_ts
```
So far, we have had four successful runs of the above
In addition,
```bash
TEST_TMPDIR=/dev/shm/rocksdb make crash_test
```
Succeeded twice showing no regression.
Reviewed By: ltamasi
Differential Revision: D37539805
Pulled By: riversand963
fbshipit-source-id: f2d9887ad95245945ce17a014d55bb93f00e1cb5
Summary:
This is the initial step in the development of a lock-free clock cache. This PR includes the base hash table design (which we mostly ported over from FastLRUCache) and the clock eviction algorithm. Importantly, it's still _not_ lock-free---all operations use a shard lock. Besides the locking, there are other features left as future work:
- Remove keys from the handles. Instead, use 128-bit bijective hashes of them for handle comparisons, probing (we need two 32-bit hashes of the key for double hashing) and sharding (we need one 6-bit hash).
- Remove the clock_usage_ field, which is updated on every lookup. Even if it were atomically updated, it could cause memory invalidations across cores.
- Middle insertions into the clock list.
- A test that exercises the clock eviction policy.
- Update the Java API of ClockCache and Java calls to C++.
Along the way, we improved the code and comments quality of FastLRUCache. These changes are relatively minor.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10273
Test Plan: ``make -j24 check``
Reviewed By: pdillinger
Differential Revision: D37522461
Pulled By: guidotag
fbshipit-source-id: 3d70b737dbb70dcf662f00cef8c609750f083943
Summary:
Before this PR, when user-defined timestamp is enabled, db_stress disables compaction filter.
This is no longer necessary after this PR, since the `DbStressCompactionFilter` is now aware of
the presence of timestamps.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10259
Test Plan: TEST_TMPDIR=/dev/shm make crash_test_with_ts
Reviewed By: ajkr
Differential Revision: D37459692
Pulled By: riversand963
fbshipit-source-id: 8fe62e90a63bd9317fe1bb95a2b4984080c9e5ef
Summary:
Need to disable it for now as CI is failing, particularly `MultiOpsTxnsStressTest`. Investigation details in internal task T124324915. This PR disables mempurge more widely than `MultiOpsTxnsStressTest` until we know the issue is contained to that particular test.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10252
Reviewed By: riversand963
Differential Revision: D37432948
Pulled By: ajkr
fbshipit-source-id: d0cf5b0e0ec7c3142c382a0347f35a4c34f4607a
Summary:
**Summary**
Make the mempurge option flag a Mutable Column Family option flag. Therefore, the mempurge feature can be dynamically toggled.
**Motivation**
RocksDB users prefer having the ability to switch features on and off without having to close and reopen the DB. This is particularly important if the feature causes issues and needs to be turned off. Dynamically changing a DB option flag does not seem currently possible.
Moreover, with this new change, the MemPurge feature can be toggled on or off independently between column families, which we see as a major improvement.
**Content of this PR**
This PR includes removal of the `experimental_mempurge_threshold` flag as a DB option flag, and its re-introduction as a `MutableCFOption` flag. I updated the code to handle dynamic changes of the flag (in particular inside the `FlushJob` file). Additionally, this PR includes a new test to demonstrate the capacity of the code to toggle the MemPurge feature on and off, as well as the addition in the `db_stress` module of 2 different mempurge threshold values (0.0 and 1.0) that can be randomly changed with the `set_option_one_in` flag. This is useful to stress test the dynamic changes.
**Benchmarking**
I will add numbers to prove that there is no performance impact within the next 12 hours.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10011
Reviewed By: pdillinger
Differential Revision: D36462357
Pulled By: bjlemaire
fbshipit-source-id: 5e3d63bdadf085c0572ecc2349e7dd9729ce1802
Summary:
In order to facilitate correctness and performance testing, we would like to add the new blob cache to our stress test tool `db_stress` and our continuously running crash test script `db_crashtest.py`, as well as our synthetic benchmarking tool `db_bench` and the BlobDB performance testing script `run_blob_bench.sh`.
As part of this task, we would also like to utilize these benchmarking tools to get some initial performance numbers about the effectiveness of caching blobs.
This PR is a part of https://github.com/facebook/rocksdb/issues/10156
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10202
Reviewed By: ltamasi
Differential Revision: D37325739
Pulled By: gangliao
fbshipit-source-id: deb65d0d414502270dd4c324d987fd5469869fa8
Summary:
There was a bug in the MultiGet enhancement in https://github.com/facebook/rocksdb/issues/9899 with data
block hash index, which was not caught because data block hash index was
never added to stress tests. This change fixes both issues.
Fixes https://github.com/facebook/rocksdb/issues/10186
I intend to pick this into the 7.4.0 release candidate
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10220
Test Plan:
Failure quickly reproduces in crash test with
kDataBlockBinaryAndHash, and does not seem to with the fix. Reproducing
the failure with a unit test I believe would be too tricky and fragile
to be worthwhile.
Reviewed By: anand1976
Differential Revision: D37315647
Pulled By: pdillinger
fbshipit-source-id: 9f648265bba867275edc752f7a56611a59401cba
Summary:
**Context/Summary:**
https://github.com/facebook/rocksdb/pull/9424 added rate-limiting support for user reads, which does not include batched `MultiGet()`s that call `RandomAccessFileReader::MultiRead()`. The reason is that it's harder (compared with RandomAccessFileReader::Read()) to implement the ideal rate-limiting where we first call `RateLimiter::RequestToken()` for allowed bytes to multi-read and then consume those bytes by satisfying as many requests in `MultiRead()` as possible. For example, it can be tricky to decide whether we want partially fulfilled requests within one `MultiRead()` or not.
However, due to a recent urgent user request, we decide to pursue an elementary (but a conditionally ineffective) solution where we accumulate enough rate limiter requests toward the total bytes needed by one `MultiRead()` before doing that `MultiRead()`. This is not ideal when the total bytes are huge as we will actually consume a huge bandwidth from rate-limiter causing a burst on disk. This is not what we ultimately want with rate limiter. Therefore a follow-up work is noted through TODO comments.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10159
Test Plan:
- Modified existing unit test `DBRateLimiterOnReadTest/DBRateLimiterOnReadTest.NewMultiGet`
- Traced the underlying system calls `io_uring_enter` and verified they are 10 seconds apart from each other correctly under the setting of `strace -ftt -e trace=io_uring_enter ./db_bench -benchmarks=multireadrandom -db=/dev/shm/testdb2 -readonly -num=50 -threads=1 -multiread_batched=1 -batch_size=100 -duration=10 -rate_limiter_bytes_per_sec=200 -rate_limiter_refill_period_us=1000000 -rate_limit_bg_reads=1 -disable_auto_compactions=1 -rate_limit_user_ops=1` where each `MultiRead()` read about 2000 bytes (inspected by debugger) and the rate limiter grants 200 bytes per seconds.
- Stress test:
- Verified `./db_stress (-test_cf_consistency=1/test_batches_snapshots=1) -use_multiget=1 -cache_size=1048576 -rate_limiter_bytes_per_sec=10241024 -rate_limit_bg_reads=1 -rate_limit_user_ops=1` work
Reviewed By: ajkr, anand1976
Differential Revision: D37135172
Pulled By: hx235
fbshipit-source-id: 73b8e8f14761e5d4b77235dfe5d41f4eea968bcd
Summary:
Added an option, `WriteOptions::protection_bytes_per_key`, that controls how many bytes per key we use for integrity protection in `WriteBatch`. It takes effect when `WriteBatch::GetProtectionBytesPerKey() == 0`.
Currently the only supported value is eight. Invoking a user API with it set to any other nonzero value will result in `Status::NotSupported` returned to the user.
There is also a bug fix for integrity protection with `inplace_callback`, where we forgot to take into account the possible change in varint length when calculating KV checksum for the final encoded buffer.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10037
Test Plan:
- Manual
- Set default value of `WriteOptions::protection_bytes_per_key` to eight and ran `make check -j24`
- Enabled in MyShadow for 1+ week
- Automated
- Unit tests have a `WriteMode` that enables the integrity protection via `WriteOptions`
- Crash test - in most cases, use `WriteOptions::protection_bytes_per_key` to enable integrity protection
Reviewed By: cbi42
Differential Revision: D36614569
Pulled By: ajkr
fbshipit-source-id: 8650087ceac9b61b560f1e5fafe5e1baf9c725fb
Summary:
In https://github.com/facebook/rocksdb/issues/9535, release 7.0, we hid the old block-based filter from being created using
the public API, because of its inefficiency. Although we normally maintain read compatibility
on old DBs forever, filters are not required for reading a DB, only for optimizing read
performance. Thus, it should be acceptable to remove this code and the substantial
maintenance burden it carries as useful features are developed and validated (such
as user timestamp).
This change completely removes the code for reading and writing the old block-based
filters, net removing about 1370 lines of code no longer needed. Options removed from
testing / benchmarking tools. The prior existence is only evident in a couple of places:
* `CacheEntryRole::kDeprecatedFilterBlock` - We can update this public API enum in
a major release to minimize source code incompatibilities.
* A warning is logged when an old table file is opened that used the old block-based
filter. This is provided as a courtesy, and would be a pain to unit test, so manual testing
should suffice. Unfortunately, sst_dump does not tell you whether a file uses
block-based filter, and the structure of the code makes it very difficult to fix.
* To detect that case, `kObsoleteFilterBlockPrefix` (renamed from `kFilterBlockPrefix`)
for metaindex is maintained (for now).
Other notes:
* In some cases where numbers are associated with filter configurations, we have had to
update the assigned numbers so that they all correspond to something that exists.
* Fixed potential stat counting bug by assuming `filter_checked = false` for cases
like `filter == nullptr` rather than assuming `filter_checked = true`
* Removed obsolete `block_offset` and `prefix_extractor` parameters from several
functions.
* Removed some unnecessary checks `if (!table_prefix_extractor() && !prefix_extractor)`
because the caller guarantees the prefix extractor exists and is compatible
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10184
Test Plan:
tests updated, manually test new warning in LOG using base version to
generate a DB
Reviewed By: riversand963
Differential Revision: D37212647
Pulled By: pdillinger
fbshipit-source-id: 06ee020d8de3b81260ffc36ad0c1202cbf463a80
Summary:
There is `Options::allow_data_in_errors` that controls whether RocksDB
is allowed to log data, e.g. key, value, etc in LOG files. It is false
by default. However, in db_bench and db_stress, it is often ok to log
data because there is no concern about privacy.
This PR allows db_stress and db_bench to set this option on the command
line, while it remains false by default. Furthermore, make
crash/recovery test driven by db_crashtest.py to opt-in.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10171
Test Plan: Stress test and db_bench
Reviewed By: hx235
Differential Revision: D37163787
Pulled By: riversand963
fbshipit-source-id: 0242f24d292ba15b6faf8ff903963b85d3e011f8
Summary:
We make the size of the per-shard hash table fixed. The base level of the hash table is now preallocated with the required capacity. The user must provide an estimate of the size of the values.
Notice that even though the base level becomes fixed, the chains are still dynamic. Overall, the shard capacity mechanisms haven't changed, so we don't need to test this.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10154
Test Plan: `make -j24 check`
Reviewed By: pdillinger
Differential Revision: D37124451
Pulled By: guidotag
fbshipit-source-id: cba6ac76052fe0ec60b8ff4211b3de7650e80d0c
Summary:
Before this PR, there can be a race condition between the thread calling
`StressTest::Open()` and a background compaction thread calling
`MultiOpsTxnsStressTest::VerifyPkSkFast()`.
```
Time thread1 bg_compact_thr
| TransactionDB::Open(..., &txn_db_)
| db_ is still nullptr
| db_->GetSnapshot() // segfault
| db_ = txn_db_
V
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10157
Test Plan: CI
Reviewed By: akankshamahajan15
Differential Revision: D37121653
Pulled By: riversand963
fbshipit-source-id: 6a53117f958e9ee86f77297fdeb843e5160a9331
Summary:
In RocksDB, keys are associated with (internal) sequence numbers which denote when the keys are written
to the database. Sequence numbers in different RocksDB instances are unrelated, thus not comparable.
It is nice if we can associate sequence numbers with their corresponding actual timestamps. One thing we can
do is to support user-defined timestamp, which allows the applications to specify the format of custom timestamps
and encode a timestamp with each key. More details can be found at https://github.com/facebook/rocksdb/wiki/User-defined-Timestamp-%28Experimental%29.
This PR provides a different but complementary approach. We can associate rocksdb snapshots (defined in
https://github.com/facebook/rocksdb/blob/7.2.fb/include/rocksdb/snapshot.h#L20) with **user-specified** timestamps.
Since a snapshot is essentially an object representing a sequence number, this PR establishes a bi-directional mapping between sequence numbers and timestamps.
In the past, snapshots are usually taken by readers. The current super-version is grabbed, and a `rocksdb::Snapshot`
object is created with the last published sequence number of the super-version. You can see that the reader actually
has no good idea of what timestamp to assign to this snapshot, because by the time the `GetSnapshot()` is called,
an arbitrarily long period of time may have already elapsed since the last write, which is when the last published
sequence number is written.
This observation motivates the creation of "timestamped" snapshots on the write path. Currently, this functionality is
exposed only to the layer of `TransactionDB`. Application can tell RocksDB to create a snapshot when a transaction
commits, effectively associating the last sequence number with a timestamp. It is also assumed that application will
ensure any two snapshots with timestamps should satisfy the following:
```
snapshot1.seq < snapshot2.seq iff. snapshot1.ts < snapshot2.ts
```
If the application can guarantee that when a reader takes a timestamped snapshot, there is no active writes going on
in the database, then we also allow the user to use a new API `TransactionDB::CreateTimestampedSnapshot()` to create
a snapshot with associated timestamp.
Code example
```cpp
// Create a timestamped snapshot when committing transaction.
txn->SetCommitTimestamp(100);
txn->SetSnapshotOnNextOperation();
txn->Commit();
// A wrapper API for convenience
Status Transaction::CommitAndTryCreateSnapshot(
std::shared_ptr<TransactionNotifier> notifier,
TxnTimestamp ts,
std::shared_ptr<const Snapshot>* ret);
// Create a timestamped snapshot if caller guarantees no concurrent writes
std::pair<Status, std::shared_ptr<const Snapshot>> snapshot = txn_db->CreateTimestampedSnapshot(100);
```
The snapshots created in this way will be managed by RocksDB with ref-counting and potentially shared with
other readers. We provide the following APIs for readers to retrieve a snapshot given a timestamp.
```cpp
// Return the timestamped snapshot correponding to given timestamp. If ts is
// kMaxTxnTimestamp, then we return the latest timestamped snapshot if present.
// Othersise, we return the snapshot whose timestamp is equal to `ts`. If no
// such snapshot exists, then we return null.
std::shared_ptr<const Snapshot> TransactionDB::GetTimestampedSnapshot(TxnTimestamp ts) const;
// Return the latest timestamped snapshot if present.
std::shared_ptr<const Snapshot> TransactionDB::GetLatestTimestampedSnapshot() const;
```
We also provide two additional APIs for stats collection and reporting purposes.
```cpp
Status TransactionDB::GetAllTimestampedSnapshots(
std::vector<std::shared_ptr<const Snapshot>>& snapshots) const;
// Return timestamped snapshots whose timestamps fall in [ts_lb, ts_ub) and store them in `snapshots`.
Status TransactionDB::GetTimestampedSnapshots(
TxnTimestamp ts_lb,
TxnTimestamp ts_ub,
std::vector<std::shared_ptr<const Snapshot>>& snapshots) const;
```
To prevent the number of timestamped snapshots from growing infinitely, we provide the following API to release
timestamped snapshots whose timestamps are older than or equal to a given threshold.
```cpp
void TransactionDB::ReleaseTimestampedSnapshotsOlderThan(TxnTimestamp ts);
```
Before shutdown, RocksDB will release all timestamped snapshots.
Comparison with user-defined timestamp and how they can be combined:
User-defined timestamp persists every key with a timestamp, while timestamped snapshots maintain a volatile
mapping between snapshots (sequence numbers) and timestamps.
Different internal keys with the same user key but different timestamps will be treated as different by compaction,
thus a newer version will not hide older versions (with smaller timestamps) unless they are eligible for garbage collection.
In contrast, taking a timestamped snapshot at a certain sequence number and timestamp prevents all the keys visible in
this snapshot from been dropped by compaction. Here, visible means (seq < snapshot and most recent).
The timestamped snapshot supports the semantics of reading at an exact point in time.
Timestamped snapshots can also be used with user-defined timestamp.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9879
Test Plan:
```
make check
TEST_TMPDIR=/dev/shm make crash_test_with_txn
```
Reviewed By: siying
Differential Revision: D35783919
Pulled By: riversand963
fbshipit-source-id: 586ad905e169189e19d3bfc0cb0177a7239d1bd4
Levi Tamasi