Summary:
When we had a single thread pool for compactions, a thread could be busy for a long time (minutes) executing a compaction involving the bottom level. In multi-instance setups, the entire thread pool could be consumed by such bottom-level compactions. Then, top-level compactions (e.g., a few L0 files) would be blocked for a long time ("head-of-line blocking"). Such top-level compactions are critical to prevent compaction stalls as they can quickly reduce number of L0 files / sorted runs.
This diff introduces a bottom-priority queue for universal compactions including the bottom level. This alleviates the head-of-line blocking situation for fast, top-level compactions.
- Added `Env::Priority::BOTTOM` thread pool. This feature is only enabled if user explicitly configures it to have a positive number of threads.
- Changed `ThreadPoolImpl`'s default thread limit from one to zero. This change is invisible to users as we call `IncBackgroundThreadsIfNeeded` on the low-pri/high-pri pools during `DB::Open` with values of at least one. It is necessary, though, for bottom-pri to start with zero threads so the feature is disabled by default.
- Separated `ManualCompaction` into two parts in `PrepickedCompaction`. `PrepickedCompaction` is used for any compaction that's picked outside of its execution thread, either manual or automatic.
- Forward universal compactions involving last level to the bottom pool (worker thread's entry point is `BGWorkBottomCompaction`).
- Track `bg_bottom_compaction_scheduled_` so we can wait for bottom-level compactions to finish. We don't count them against the background jobs limits. So users of this feature will get an extra compaction for free.
Closes https://github.com/facebook/rocksdb/pull/2580
Differential Revision: D5422916
Pulled By: ajkr
fbshipit-source-id: a74bd11f1ea4933df3739b16808bb21fcd512333
Summary:
I'm going with brute-force solution, just letting Put() and Write() holding a mutex before writing. May improve concurrent writing with finer granularity locking later.
Closes https://github.com/facebook/rocksdb/pull/2682
Differential Revision: D5552690
Pulled By: yiwu-arbug
fbshipit-source-id: 039abd675b5d274a7af6428198d1733cafecef4c
Summary:
Fix the bug where if blob db garbage collection revmoe keys with newer version. It shouldn't delete the key from base db when sequence number in base db is not equal to the one in blob log.
Closes https://github.com/facebook/rocksdb/pull/2678
Differential Revision: D5549752
Pulled By: yiwu-arbug
fbshipit-source-id: abb8649260963b5c389748023970fd746279d227
Summary:
This patch refactors TransactionImpl by separating the logic for pessimistic concurrency control from the implementation of how to write the data to rocksdb. The existing implementation is named WriteCommittedTxnImpl as it writes committed data to the db. A template named WritePreparedTxnImpl is also added which will be later completed to provide a an alternative implementation.
Closes https://github.com/facebook/rocksdb/pull/2676
Differential Revision: D5549998
Pulled By: maysamyabandeh
fbshipit-source-id: 16298e86b43ca4849324c1f35c731913c6d17bec
Summary:
Move an option necessary for running db_bench on multiple CFs into the general initialization area, so it works with both flag-based init and OPTIONS-based init.
Closes https://github.com/facebook/rocksdb/pull/2675
Differential Revision: D5541378
Pulled By: ajkr
fbshipit-source-id: 169926cb4ae95c17974f744faf7cc794d41e5c0a
Summary:
I observed while doing a `make jtest` that the java sample was broken, due to the changes in #2551 .
Closes https://github.com/facebook/rocksdb/pull/2674
Differential Revision: D5539807
Pulled By: sagar0
fbshipit-source-id: 2c7e9d84778099dfa1c611996b444efe3c9fd466
Summary:
* Dump blob db options to info log
* Remove BlobDBOptionsImpl to disallow dynamic cast *BlobDBOptions into *BlobDBOptionsImpl. Move options there to be constants or into BlobDBOptions. The dynamic cast is broken after #2645
* Change some of the default options
* Remove blob_db_options.min_blob_size, which is unimplemented. Will implement it soon.
Closes https://github.com/facebook/rocksdb/pull/2671
Differential Revision: D5529912
Pulled By: yiwu-arbug
fbshipit-source-id: dcd58ca981db5bcc7f123b65a0d6f6ae0dc703c7
Summary:
this value ``` Compaction::is_trivial_move_ ``` uninitialized .
under universal compaction , we enable ``` CompactionOptionsUniversal::allow_trivial_move ``` ,
9b11d4345a/db/compaction.cc (L245)
here is a disastrous bug , some sst trivial move to target level without overlap check ...
THEN , DATABASE DAMAGED , WE GOT A LEVEL WITH OVERLAP !
Closes https://github.com/facebook/rocksdb/pull/2634
Differential Revision: D5530722
Pulled By: siying
fbshipit-source-id: 425ab55bca5967110377d634258360bcf88c200e
Summary:
we were passing `record_read_stats` (a bool) as the `hist_type` argument, which meant we were updating either `rocksdb.db.get.micros` (`hist_type == 0`) or `rocksdb.db.write.micros` (`hist_type == 1`) with wrong data.
Closes https://github.com/facebook/rocksdb/pull/2666
Differential Revision: D5520384
Pulled By: ajkr
fbshipit-source-id: 2f7c956aec32f8b58c5c18845ac478e0230c9516
Summary:
Replace dynamic_cast<> so that users can choose to build with RTTI off, so that they can save several bytes per object, and get tiny more memory available.
Some nontrivial changes:
1. Add Comparator::GetRootComparator() to get around the internal comparator hack
2. Add the two experiemental functions to DB
3. Add TableFactory::GetOptionString() to avoid unnecessary casting to get the option string
4. Since 3 is done, move the parsing option functions for table factory to table factory files too, to be symmetric.
Closes https://github.com/facebook/rocksdb/pull/2645
Differential Revision: D5502723
Pulled By: siying
fbshipit-source-id: fd13cec5601cf68a554d87bfcf056f2ffa5fbf7c
Summary:
This fixes OOMs that we (logdevice) are currently having in production.
SkipListRep constructor does a couple small allocations from ConcurrentArena (see InlineSkipList constructor). ConcurrentArena would sometimes allocate an entire block for that, which is a few megabytes (we use Options::arena_block_size = 4 MB). So an empty memtable can take take 4 MB of memory. We have ~40k column families (spread across 15 DB instances), so 4 MB per empty memtable easily OOMs a machine for us.
This PR makes ConcurrentArena always allocate from Arena's inline block when possible. So as long as InlineSkipList's initial allocations are below 2 KB there would be no blocks allocated for empty memtables.
Closes https://github.com/facebook/rocksdb/pull/2569
Differential Revision: D5404029
Pulled By: al13n321
fbshipit-source-id: 568ec22a3fd1a485c06123f6b2dfc5e9ef67cd23
Summary:
- FIFOCompactionWithTTLTest was flaky when run in parallel earlier, and hence it was disabled. Fixed it now.
- Also, faking sleep now instead of really sleeping to make tests more realistic by using TTLs like 1 hour and 1 day.
Closes https://github.com/facebook/rocksdb/pull/2650
Differential Revision: D5506038
Pulled By: sagar0
fbshipit-source-id: deb429a527f045e3e2c5138b547c3e8ac8586aa2
Summary:
I might have missed these while doing some recent cassandra code reviews.
Closes https://github.com/facebook/rocksdb/pull/2663
Differential Revision: D5520138
Pulled By: sagar0
fbshipit-source-id: 340930afe9efe03c75f535a1da1f89bd3e53c1f9
Summary:
Simple component that will add a new entry in a log file every time we lookup/insert a key in SimCache.
API:
```
SimCache::StartActivityLogging(<file_name>, <env>, <optional_max_size>)
SimCache::StopActivityLogging()
```
Sending for review, Still need to add more comments.
I was thinking about a better approach, but I ended up deciding I will use a mutex to sync the writes to the file, since this feature should not be heavily used and only used to collect info that will be analyzed offline. I think it's okay to hold the mutex every time we lookup/add to the SimCache.
Closes https://github.com/facebook/rocksdb/pull/2295
Differential Revision: D5063826
Pulled By: IslamAbdelRahman
fbshipit-source-id: f3b5daed8b201987c9a071146ddd5c5740a2dd8c
Summary:
Introducing blob_db::TTLExtractor to replace extract_ttl_fn. The TTL
extractor can be use to extract TTL from keys insert with Put or
WriteBatch. Change over existing extract_ttl_fn are:
* If value is changed, it will be return via std::string* (rather than Slice*). With Slice* the new value has to be part of the existing value. With std::string* the limitation is removed.
* It can optionally return TTL or expiration.
Other changes in this PR:
* replace `std::chrono::system_clock` with `Env::NowMicros` so that I can mock time in tests.
* add several TTL tests.
* other minor naming change.
Closes https://github.com/facebook/rocksdb/pull/2659
Differential Revision: D5512627
Pulled By: yiwu-arbug
fbshipit-source-id: 0dfcb00d74d060b8534c6130c808e4d5d0a54440
Summary:
Breaking commit: d12691b86f
In the above commit, I moved the `TableCache` cleanup logic from `Version` destructor into `PurgeObsoleteFiles`. I missed cleaning up `TableCache` entries for the current `Version` during DB destruction.
This PR adds that logic to `VersionSet` destructor. One unfortunate side effect is now we're potentially deleting `TableReader`s after `column_family_set_.reset()`, which means we can't call `BlockBasedTableReader::Close` a second time as the block cache might already be destroyed.
Closes https://github.com/facebook/rocksdb/pull/2662
Differential Revision: D5515108
Pulled By: ajkr
fbshipit-source-id: 2cb820e19aa813e0d258d17f76b2d7b6b7ee0b18
Summary:
We don't need to set them explicitly.
Closes https://github.com/facebook/rocksdb/pull/2660
Differential Revision: D5514141
Pulled By: yiwu-arbug
fbshipit-source-id: 10edebfc3cfe0afc00a34519f87fcea4d65069ae
Summary:
platform_dependent tests in Travis now builds all tests, which is not needed. Only build those tests we need to run.
Closes https://github.com/facebook/rocksdb/pull/2647
Differential Revision: D5513954
Pulled By: siying
fbshipit-source-id: 4d540b146124e70dd25586c47939d19f93655b0a
Summary:
This is to work around the problem of build error:
util/threadpool_imp.o: file not recognized: File truncated
Just to make the build go through. We should remove it later if we find the real long-term solution.
Closes https://github.com/facebook/rocksdb/pull/2657
Differential Revision: D5511034
Pulled By: siying
fbshipit-source-id: 229f024bd78ee96799017d4a89be74253058ec30
Summary:
Post-compaction work holds onto db mutex for the longest time (found by tracing lock acquires/releases with LTTng and correlating timestamps with our info log). Further experimentation showed `TableCache::EraseHandle` is responsible for ~86% of time mutex is held. We can just release the handle outside the db mutex.
Closes https://github.com/facebook/rocksdb/pull/2654
Differential Revision: D5507126
Pulled By: ajkr
fbshipit-source-id: 703c01ddf2aea16bc0f9e33c08935d78aa6b781d
Summary:
it should be a bool
Closes https://github.com/facebook/rocksdb/pull/2653
Differential Revision: D5506148
Pulled By: ajkr
fbshipit-source-id: f142f0f3aa8b678c68adef12e5ac6e1e163306f3
Summary:
A FIFO compaction picker test is accidentally testing against an instance of level compaction picker.
Closes https://github.com/facebook/rocksdb/pull/2641
Differential Revision: D5495390
Pulled By: sagar0
fbshipit-source-id: 301962736f629b1c499570fb504cdbe66bacb46f
Summary:
We initially had disabled support for write_options.sync when concurrent_prepare_ is set. We later added this support but the statement that asserts this combination is not used was left there. This patch cleans it up.
Closes https://github.com/facebook/rocksdb/pull/2642
Differential Revision: D5496101
Pulled By: maysamyabandeh
fbshipit-source-id: becbc503446f2a51bee24cc861958c090c724ec2
Summary:
The test is failing occasionally on the assert: `ASSERT_TRUE(writer->state == WriteThread::State::STATE_INIT)`. This is because the test don't make the leader wait for long enough before updating state for its followers. The patch move the update to `threads_waiting` to the end of `WriteThread::JoinBatchGroup:Wait` callback to avoid this happening.
Also adding `WriteThread::JoinBatchGroup:Start` and have each thread wait there while another thread is linking to the linked-list. This is to make the check of `is_leader` more deterministic.
Also changing two while-loops of `compare_exchange_strong` to plain `fetch_add`, to make it look cleaner.
Closes https://github.com/facebook/rocksdb/pull/2640
Differential Revision: D5491525
Pulled By: yiwu-arbug
fbshipit-source-id: 6e897f122082bd6f98e6d51b31a25e5fd0a3fb82
Summary: These are implied by default platform flags, in particular, `-march=corei7`.
Reviewed By: pixelb
Differential Revision: D5485414
fbshipit-source-id: 85f1329c71fa81a604760844187cc73877fb40e9
Summary:
Currently this test times out with tsan. This is likely due to decreased speed with tsan. By lowering the number of iterations we can still catch a bug as the test is run regularly and multiple runs of the test is equivalent with running the test with more iterations.
Closes https://github.com/facebook/rocksdb/pull/2639
Differential Revision: D5490549
Pulled By: maysamyabandeh
fbshipit-source-id: bd69c42a9728d337ac95a06a401088384e51731a
Summary:
Fixes broken links to the introductory talk I stumbled upon while
reading the documentation.
Closes https://github.com/facebook/rocksdb/pull/2628
Differential Revision: D5483851
Pulled By: sagar0
fbshipit-source-id: 94aab7fb4c4ed2305680a2fbc65b14c7977af6b8
Summary:
We will divide by zero if `stats.micros` is zero, just add a simple check
This happens sometimes during running tests and UBSAN complains
Closes https://github.com/facebook/rocksdb/pull/2631
Differential Revision: D5481455
Pulled By: IslamAbdelRahman
fbshipit-source-id: 69aa24e64e21de15d9e2b8009adf01675fcc6598
Summary:
I haven't looked to see if a class variable inside a loop like this is always initialised.
Closes https://github.com/facebook/rocksdb/pull/2602
Differential Revision: D5475937
Pulled By: IslamAbdelRahman
fbshipit-source-id: 8570b308f9a4b49e2a56ccc9e9b84d7c46568c15
Summary:
As explained in the comments, Sometimes we create Slice(nullptr, 0) in our code base which cause us to do calls like
```
memcmp(nullptr, "abc", 0);
```
That's fine since the len is equal 0, but UBSAN is not happy about it
so disable UBSAN for this function and add an assert instead
Closes https://github.com/facebook/rocksdb/pull/2616
Differential Revision: D5458326
Pulled By: IslamAbdelRahman
fbshipit-source-id: cfca32abe30f7d8f760c9f77ecd9543dfb1170dd
Summary:
simply enable the macro in internal build, it wont hurt other sanitizers and will fix UBSAN issues
Closes https://github.com/facebook/rocksdb/pull/2625
Differential Revision: D5475897
Pulled By: IslamAbdelRahman
fbshipit-source-id: 262c6fd5de3c1906f4b29e55b39110f125f41057
Summary:
Add and implement Iterator::Refresh(). When this function is called, if the super version doesn't change, update the sequence number of the iterator to the latest one and invalidate the iterator. If the super version changed, recreated the whole iterator. This can help users reuse the iterator more easily.
Closes https://github.com/facebook/rocksdb/pull/2621
Differential Revision: D5464500
Pulled By: siying
fbshipit-source-id: f548bd35e85c1efca2ea69273802f6704eba6ba9
Summary:
The previous implementation of caching `file_size` index made no sense. It only remembered the original span of locked files starting from beginning of `file_size`. We should remember the index after all compactions that have been considered but rejected. This will reduce the work we do while holding the db mutex.
Closes https://github.com/facebook/rocksdb/pull/2624
Differential Revision: D5468152
Pulled By: ajkr
fbshipit-source-id: ab92a4bffe76f9f174d861bb5812b974d1013400
Summary:
This reverts the previous commit 1d7048c598, which broke the build.
Did a `git revert 1d7048c`.
Closes https://github.com/facebook/rocksdb/pull/2627
Differential Revision: D5476473
Pulled By: sagar0
fbshipit-source-id: 4756ff5c0dfc88c17eceb00e02c36176de728d06
Summary: This uses `clang-tidy` to comment out unused parameters (in functions, methods and lambdas) in fbcode. Cases that the tool failed to handle are fixed manually.
Reviewed By: igorsugak
Differential Revision: D5454343
fbshipit-source-id: 5dee339b4334e25e963891b519a5aa81fbf627b2
