cherry-pick compaction enhancements #345
Closed
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
tabokie
force-pushed
the
pick-compaction
branch
2 times, most recently
from
ffc19c4 to
3842074
Compare
Summary: Remove deprecated remote compaction APIs `CompactionService::Start()` and `CompactionService::WaitForComplete()`. Please use `CompactionService::StartV2()`, `CompactionService::WaitForCompleteV2()` instead, which provides the same information plus extra data like priority, db_id, etc. Pull Request resolved: facebook#9570 Test Plan: CI Reviewed By: riversand963 Differential Revision: D34255969 Pulled By: jay-zhuang fbshipit-source-id: c6376eccdd1123f1c42ab53771b5f65f8160c325 Signed-off-by: tabokie <[email protected]>
This reverts commit 2dfbfa5. Signed-off-by: tabokie <[email protected]>
Summary: Add event callback for subcompaction and adds a sub_job_id to identify it. Pull Request resolved: facebook#9311 Reviewed By: ajkr Differential Revision: D33892707 Pulled By: jay-zhuang fbshipit-source-id: 57b5e5e594d61b2112d480c18a79a36751f65a4e Signed-off-by: tabokie <[email protected]>
) Summary: Add the ability to cancel remote compaction on the remote side by setting `OpenAndCompactOptions.canceled` to true. Pull Request resolved: facebook#9725 Test Plan: added unittest Reviewed By: ajkr Differential Revision: D35018800 Pulled By: jay-zhuang fbshipit-source-id: be3652f9645e0347df429e42a5614d5a9b3a1ec4 Signed-off-by: tabokie <[email protected]>
…book#10057) Summary: The current level targets for dynamical leveling has a problem: the target level size will dramatically change after a L0->L1 compaction. When there are many L0 bytes, lower level compactions are delayed, but they will be resumed after the L0->L1 compaction finishes, so the expected write amplification benefits might not be realized. The proposal here is to revert the level targetting size, but instead relying on adjusting score for each level to prioritize levels that need to compact most. Basic idea: (1) target level size isn't adjusted, but score is adjusted. The reasoning is that with parallel compactions, holding compactions from happening might not be desirable, but we would like the compactions are scheduled from the level we feel most needed. For example, if we have a extra-large L2, we would like all compactions are scheduled for L2->L3 compactions, rather than L4->L5. This gets complicated when a large L0->L1 compaction is going on. Should we compact L2->L3 or L4->L5. So the proposal for that is: (2) the score is calculated by actual level size / (target size + estimated upper bytes coming down). The reasoning is that if we have a large amount of pending L0/L1 bytes coming down, compacting L2->L3 might be more expensive, as when the L0 bytes are compacted down to L2, the actual L2->L3 fanout would change dramatically. On the other hand, when the amount of bytes coming down to L5, the impacts to L5->L6 fanout are much less. So when calculating target score, we can adjust it by adding estimated downward bytes to the target level size. Pull Request resolved: facebook#10057 Test Plan: Repurpose tests VersionStorageInfoTest.MaxBytesForLevelDynamicWithLargeL0_* tests to cover this scenario. Reviewed By: ajkr Differential Revision: D37539742 fbshipit-source-id: 9c154cbfe92023f918cf5d80875d8776ad4831a4 Signed-off-by: tabokie <[email protected]>
Summary: As pointed out by [https://github.com/facebook/rocksdb/pull/8351#discussion_r645765422](https://github.com/facebook/rocksdb/pull/8351#discussion_r645765422), check `manual_compaction_paused` and `manual_compaction_canceled` can be reduced by setting `*canceled` to be true in `DisableManualCompaction()` and `*canceled` to be false in the last time calling `EnableManualCompaction()`. Changed Tests: The origin `DBTest2.PausingManualCompaction1` uses a callback function to increase `manual_compaction_paused` and the origin CompactionJob/CompactionIterator with `manual_compaction_paused` can detect this. I changed the callback function so that it sets `*canceled` as true if `canceled` is not `nullptr` (to notify CompactionJob/CompactionIterator the compaction has been canceled). Pull Request resolved: facebook#10070 Test Plan: This change does not introduce new features, but some slight difference in compaction implementation. Run the same manual compaction unit tests as before (e.g., PausingManualCompaction[1-4], CancelManualCompaction[1-2], CancelManualCompactionWithListener in db_test2, and db_compaction_test). Reviewed By: ajkr Differential Revision: D36949133 Pulled By: littlepig2013 fbshipit-source-id: c5dc4c956fbf8f624003a0f5ad2690240063a821 Signed-off-by: tabokie <[email protected]>
Summary: This PR changes the default value of `CompactRangeOptions::exclusive_manual_compaction` from true to false so manual `CompactRange()`s can run in parallel with other compactions. I believe no artificial parallelism restriction is the intuitive behavior so feel the old default value is a trap, which I have fallen into several times, including yesterday. `CompactRangeOptions::exclusive_manual_compaction == false` has been used in both our correctness test and in production for years so should be reasonably safe. Pull Request resolved: facebook#10317 Reviewed By: jay-zhuang Differential Revision: D37659392 Pulled By: ajkr fbshipit-source-id: 504915e978bbe300b79483d064070c75e93d91e5 Signed-off-by: tabokie <[email protected]>
Summary: facebook#10057 caused a regression bug: since the base level size is not adjusted based on L0 size anymore, L0 score might become very large. This makes compaction heavily favor L0->L1 compaction against L1->L2 compaction, and cause in some cases, data stuck in L1 without being moved down. We fix calculating a score of L0 by size(L0)/size(L1) in the case where L0 is large.. Pull Request resolved: facebook#10518 Test Plan: run db_bench against data on tmpfs and watch the behavior of data stuck in L1 goes away. Reviewed By: ajkr Differential Revision: D38603145 fbshipit-source-id: 4949e52dc28b54aacfe08417c6e6cc7e40a27225 Signed-off-by: tabokie <[email protected]>
Summary: Right now, in unit tests, when background tests are sleeping using SleepingBackgroundTask, and the test exits with test assertion failure, the process will hang and it might prevent us to see the test failure message in CI runs. Try to wake up the thread so that the test can exit correctly. Pull Request resolved: facebook#11036 Test Plan: Watch CI succeeds Reviewed By: riversand963 Differential Revision: D42020489 fbshipit-source-id: 5b8441b18d5f67bbb3ade59a1225a8d3c860c2eb Signed-off-by: tabokie <[email protected]>
…ction (facebook#11165) Summary: This PR adds logic to the `RunManualCompaction()` loop to check for cancellation before waiting on any conflicting compactions to finish. In case of cancellation, `RunManualCompaction()` no longer waits on conflicting compactions Pull Request resolved: facebook#11165 Test Plan: repro test case Reviewed By: cbi42 Differential Revision: D42864058 Pulled By: ajkr fbshipit-source-id: ea4dd1a8f294abe212905495a8fbe8f07fca3f5a Signed-off-by: tabokie <[email protected]>
…ic_l… (facebook#11321) Summary: …evel_bytes During DB open, if a column family uses level compaction with level_compaction_dynamic_level_bytes=true, trivially move its files down in the LSM such that the bottommost files are in Lmax, the second from bottommost level files are in Lmax-1 and so on. This is aimed to make it easier to migrate level_compaction_dynamic_level_bytes from false to true. Before this change, a full manual compaction is suggested for such migration. After this change, user can just restart DB to turn on this option. db_crashtest.py is updated to randomly choose value for level_compaction_dynamic_level_bytes. Note that there may still be too many unnecessary levels if a user is migrating from universal compaction or level compaction with a smaller level multiplier. A full manual compaction may still be needed in that case before some PR that automatically drain unnecessary levels like facebook#3921 lands. Eventually we may want to change the default value of option level_compaction_dynamic_level_bytes to true. Pull Request resolved: facebook#11321 Test Plan: 1. Added unit tests. 2. Crash test: ran a variation of db_crashtest.py (like 3251650) that turns level_compaction_dynamic_level_bytes on and off and switches between LC and UC for the same DB. TODO: Update `OptionChangeMigration`, either after this PR or facebook#3921. Reviewed By: ajkr Differential Revision: D44341930 Pulled By: cbi42 fbshipit-source-id: 013de19a915c6a0502be569f07c4cc8f1c3c6be2 Signed-off-by: tabokie <[email protected]>
…rue` (facebook#11340) Summary: When a user migrates to level compaction + `level_compaction_dynamic_level_bytes=true`, or when a DB shrinks, there can be unnecessary levels in the DB. Before this PR, this is no way to remove these levels except a manual compaction. These extra unnecessary levels make it harder to guarantee max_bytes_for_level_multiplier and can cause extra space amp. This PR boosts compaction score for these levels to allow RocksDB to automatically drain these levels. Together with facebook#11321, this makes migration to `level_compaction_dynamic_level_bytes=true` automatic without needing user to do a one time full manual compaction. Credit: this PR is modified from facebook#3921. Pull Request resolved: facebook#11340 Test Plan: - New unit tests - `python3 tools/db_crashtest.py whitebox --simple` which randomly sets level_compaction_dynamic_level_bytes in each run. Reviewed By: ajkr Differential Revision: D44563884 Pulled By: cbi42 fbshipit-source-id: e20d3620bd73dff22be18c5a91a07f340740bcc8 Signed-off-by: tabokie <[email protected]>
…1375) Summary: during manual compaction (CompactRange()), L0->L1 trivial move is disabled when only L0 overlaps with compacting key range (introduced in facebook#7368 to enforce kForce* contract). This can cause large memory usage due to compaction readahead when number of L0 files is large. This PR allows L0->L1 trivial move in this case, and will do a L1 -> L1 intra-level compaction when needed (`bottommost_level_compaction` is kForce*). In brief, consider a DB with only L0 file, and user calls CompactRange(kForce, nullptr, nullptr), - before this PR, RocksDB does a L0 -> L1 compaction (disallow trivial move), - after this PR, RocksDB does a L0 -> L1 compaction (allow trivial move), and a L1 -> L1 compaction. Users can use kForceOptimized to avoid this extra L1->L1 compaction overhead when L0s are overlapping and cannot be trivial moved. This PR also fixed a bug (see previous discussion in facebook#11041) where `final_output_level` of a manual compaction can be miscalculated when `level_compaction_dynamic_level_bytes=true`. This bug could cause incorrect level being moved when CompactRangeOptions::change_level is specified. Pull Request resolved: facebook#11375 Test Plan: - Added new unit tests to test that L0 -> L1 compaction allows trivial move and L1 -> L1 compaction is done when needed. Reviewed By: ajkr Differential Revision: D44943518 Pulled By: cbi42 fbshipit-source-id: e9fb770d17b163c18a623e1d1bd6b81159192708 Signed-off-by: tabokie <[email protected]>
…action (facebook#11468) Summary: currently for leveled compaction, the max output level of a call to `CompactRange()` is pre-computed before compacting each level. This max output level is the max level whose key range overlaps with the manual compaction key range. However, during manual compaction, files in the max output level may be compacted down further by some background compaction. When this background compaction is a trivial move, there is a race condition and the manual compaction may not be able to compact all keys in the specified key range. This PR updates `CompactRange()` to always compact to the bottommost level to make this race condition more unlikely (it can still happen, see more in comment here: https://github.com/cbi42/rocksdb/blob/796f58f42ad1bdbf49e5fcf480763f11583b790e/db/db_impl/db_impl_compaction_flush.cc#L1180C29-L1184). This PR also changes the behavior of CompactRange() when `bottommost_level_compaction=kIfHaveCompactionFilter` (the default option). The old behavior is that, if a compaction filter is provided, CompactRange() always does an intra-level compaction at the final output level for all files in the manual compaction key range. The only exception when `first_overlapped_level = 0` and `max_overlapped_level = 0`. It’s awkward to maintain the same behavior after this PR since we do not compute max_overlapped_level anymore. So the new behavior is similar to kForceOptimized: always does intra-level compaction at the bottommost level, but not including new files generated during this manual compaction. Several unit tests are updated to work with this new manual compaction behavior. Pull Request resolved: facebook#11468 Test Plan: Add new unit tests `DBCompactionTest.ManualCompactionCompactAllKeysInRange*` Reviewed By: ajkr Differential Revision: D46079619 Pulled By: cbi42 fbshipit-source-id: 19d844ba4ec8dc1a0b8af5d2f36ff15820c6e76f Signed-off-by: tabokie <[email protected]>
tabokie
force-pushed
the
pick-compaction
branch
from
3842074 to
fa57fe0
Compare
|
Can rocksdb's UT pass with this change @tabokie |
Signed-off-by: tabokie <[email protected]>
tabokie
force-pushed
the
pick-compaction
branch
from
03aede8 to
2f183c0
Compare
All tests are run in CI and they have passed. |
|
Superseded by #346 |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
level_compaction_dynamic_level_bytes=truefacebook/rocksdb#11340CompactRange()always compacts to bottommost level for leveled compaction facebook/rocksdb#11468Unfortunately facebook#10655 is not included because it depends on a big refactor earlier.
Retiring our own changes:
Signed-off-by: tabokie [email protected]