Summary:
This diff update DB::CompactRange to use RangeCompactionOptions instead of using multiple parameters
Old CompactRange is still available but deprecated

Test Plan:
make all check
make rocksdbjava
USE_CLANG=1 make all
OPT=-DROCKSDB_LITE make release

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D40209

Summary:
We go to great lengths to make sure MaybeScheduleFlushOrCompaction() is called outside of write thread. But anyway, it's still called in the mutex, so it's not that much cheaper.

This diff removes the "optimization" and cleans up the code a bit.

Test Plan: make check

Reviewers: rven, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D40113

Summary:
Add an option in GetApproximateSize() so that the result will include estimated sizes in mem tables.
To implement it, implement an estimated count from the beginning to a key in skip list. The approach is to count to find the entry, how many Next() is issued from each level, and sum them with a weight that is <branching factor> ^ <level>.

Test Plan: Add a test case

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D40119

Summary:
Reverting this diff https://reviews.facebook.net/D39999
Will add an option to force bottom most level compaction and then re submit it

Test Plan: make check

Reviewers: igor, sdong

Reviewed By: sdong

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D40041

Summary: If we don't have a compaction filter then we can skip compacting the bottom most level

Test Plan:
make check
added unit tests

Reviewers: yhchiang, sdong, igor

Reviewed By: sdong

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D39999

Summary:
We slow down data into the database to the rate of options.delayed_write_rate (a new option) with this patch.

The thread synchronization approach I take is to still synchronize write controller by DB mutex and GetDelay() is inside DB mutex. Try to minimize the frequency of getting time in GetDelay(). I verified it through db_bench and it seems to work

hard_rate_limit is deprecated.

options.delayed_write_rate is still not dynamically changeable. Need to work on it as a follow-up.

Test Plan: Add new unit tests in db_test

Reviewers: yhchiang, rven, kradhakrishnan, anthony, MarkCallaghan, igor

Reviewed By: igor

Subscribers: ikabiljo, leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D36351

Summary:
Adding largest sequence number to FlushJobInfo
and passing flushed file metadata to NotifyOnFlushCompleted which include alot of other values that we may want to expose in FlushJobInfo

Test Plan: make check

Reviewers: igor, sdong

Reviewed By: sdong

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D39927

Summary:
Add Env::GetThreadID(), which returns the ID of the current thread.

In addition, make GetThreadList() and InfoLog use same unique ID for the same thread.

Test Plan:
db_test
listener_test

Reviewers: igor, rven, IslamAbdelRahman, kradhakrishnan, sdong

Reviewed By: sdong

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D39735

Summary:
Right now the level we pass to ReFitLevel is the maximum level with files (before compaction), there are multiple cases where this maximum level have changed after compaction
- all files where in L0 (now maximum level is L1)
- using kCompactionStyleUniversal (now maximum level in the last level)
- level_compaction_dynamic_level_bytes ??

We can handle each of these cases individually, but I felt it's safer to calculate max_level_with_files again if we want to do a ReFitLevel

Test Plan:
adding some tests
make -j64 check

Reviewers: igor, sdong

Reviewed By: sdong

Subscribers: ott, dhruba

Differential Revision: https://reviews.facebook.net/D39663

Summary:
There is a hang during DB close in the following scenario:
a) a load with WAL disabled was done,
b) CancelAllBackgroundWork was called,
c) DB Close was called
This was because in that we will wait for a flush but we cannot do a
background flush because we have called CancelAllBackgroundWork which
marks the DB as shutting downn.

Test Plan: Added DBTest FlushOnDestroy

Reviewers: sdong

Reviewed By: sdong

Subscribers: yoshinorim, hermanlee4, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D39747

Summary: We currently issue malloc and free inside DB mutex in GetSnapshot() and ReleaseSnapshot(). Move them out.

Test Plan:
Go through all tests
make valgrind_check

Reviewers: yhchiang, rven, IslamAbdelRahman, anthony, igor

Reviewed By: igor

Subscribers: maykov, hermanlee4, MarkCallaghan, yoshinorim, leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D39753

Summary:
It is experimental. Allow users to return from a call back function TablePropertiesCollector::NeedCompact(), based on the data in the file.
It can be used to allow users to suggest DB to clear up delete tombstones faster.

Test Plan: Add a unit test.

Reviewers: igor, yhchiang, kradhakrishnan, rven

Reviewed By: rven

Subscribers: yoshinorim, MarkCallaghan, maykov, leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D39585

Summary:
EventListener::OnFlushCompleted() now passes a structure instead
of a list of parameters.  This minimizes the API change in the
future.

Test Plan:
listener_test
compact_files_test
example/compact_files_example

Reviewers: kradhakrishnan, sdong, IslamAbdelRahman, rven, igor

Reviewed By: rven, igor

Subscribers: IslamAbdelRahman, rven, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D39543

Summary: Revert incorrect commit

Test Plan: db_test

Reviewers: sdong, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D39651

Summary: I encountered an issue where the database hang, it looks like the mutex is not unlocked on return in ReFitLevel function

Test Plan: make -j64 check

Reviewers: yhchiang, sdong

Reviewed By: sdong

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D39609

Summary:
The type of smallest_output_key_prefix and largest_output_key_prefix
have been changed to std::string in https://reviews.facebook.net/D39537.
As a result, we shouldn't do smallest_output_key_prefix[0] = 0 in the
initialization.

Test Plan: compile db_test with tsan enabled and repeat DBTest.CompactionDeletionTrigger test to verify the tsan issue has been gone.

Reviewers: igor, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D39645

Summary:
This diff updates the logic of how we do trivial move, now trivial move can run on any number of files in input level as long as they are not overlapping

The conditions for trivial move have been updated

Introduced conditions:
  - Trivial move cannot happen if we have a compaction filter (except if the compaction is not manual)
  - Input level files cannot be overlapping

Removed conditions:
  - Trivial move only run when the compaction is not manual
  - Input level should can contain only 1 file

More context on what tests failed because of Trivial move
```
DBTest.CompactionsGenerateMultipleFiles
This test is expecting compaction on a file in L0 to generate multiple files in L1, this test will fail with trivial move because we end up with one file in L1
```

```
DBTest.NoSpaceCompactRange
This test expect compaction to fail when we force environment to report running out of space, of course this is not valid in trivial move situation
because trivial move does not need any extra space, and did not check for that
```

```
DBTest.DropWrites
Similar to DBTest.NoSpaceCompactRange
```

```
DBTest.DeleteObsoleteFilesPendingOutputs
This test expect that a file in L2 is deleted after it's moved to L3, this is not valid with trivial move because although the file was moved it is now used by L3
```

```
CuckooTableDBTest.CompactionIntoMultipleFiles
Same as DBTest.CompactionsGenerateMultipleFiles
```

This diff is based on a work by @sdong https://reviews.facebook.net/D34149

Test Plan: make -j64 check

Reviewers: rven, sdong, igor

Reviewed By: igor

Subscribers: yhchiang, ott, march, dhruba, sdong

Differential Revision: https://reviews.facebook.net/D34797

Summary:
Add EventListener::OnTableFileDeletion(), which will be
called when a table file is deleted.

Test Plan: Extend three existing tests in db_test to verify the deleted files.

Reviewers: rven, anthony, kradhakrishnan, igor, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38931

Summary:
Fix the following compile warning in db/db_impl

  db/db_impl.cc:1603:19: error: implicit conversion loses integer precision: 'const uint64_t' (aka 'const unsigned long') to 'int' [-Werror,-Wshorten-64-to-32]
     info.job_id = job_id;
                 ~ ^~~~~~

Test Plan: db_test

Reviewers: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D39423

Summary:
Allow EventListener::OnCompactionCompleted to return CompactionJobStats,
which contains useful information about a compaction.

Example CompactionJobStats returned by OnCompactionCompleted():
    smallest_output_key_prefix 05000000
    largest_output_key_prefix 06990000
    elapsed_time 42419
    num_input_records 300
    num_input_files 3
    num_input_files_at_output_level 2
    num_output_records 200
    num_output_files 1
    actual_bytes_input 167200
    actual_bytes_output 110688
    total_input_raw_key_bytes 5400
    total_input_raw_value_bytes 300000
    num_records_replaced 100
    is_manual_compaction 1

Test Plan: Developed a mega test in db_test which covers 20 variables in CompactionJobStats.

Reviewers: rven, igor, anthony, sdong

Reviewed By: sdong

Subscribers: tnovak, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38463

Summary:
Add EventListener::OnTableFileCreated(), which will be called
when a table file is created.  This patch is part of the
EventLogger and EventListener integration.

Test Plan: Augment existing test in db/listener_test.cc

Reviewers: anthony, kradhakrishnan, rven, igor, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38865

Summary: Add a stats counter for DB_WRITE back which was mistakenly removed.

Test Plan: augment GroupCommitTest

Reviewers: sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D39399

Summary:
We occasionally get write stalls (>1s Write() calls) on HDD under read load. The following timers explain almost all of the stalls:
 - perf_context.db_mutex_lock_nanos
 - perf_context.db_condition_wait_nanos
 - iostats_context.open_time
 - iostats_context.allocate_time
 - iostats_context.write_time
 - iostats_context.range_sync_time
 - iostats_context.logger_time

In my experiments each of these occasionally takes >1s on write path under some workload. There are rare cases when Write() takes long but none of these takes long.

Test Plan: Added code to our application to write the listed timings to log for slow writes. They usually add up to almost exactly the time Write() call took.

Reviewers: rven, yhchiang, sdong

Reviewed By: sdong

Subscribers: march, dhruba, tnovak

Differential Revision: https://reviews.facebook.net/D39177

Summary: In DB::CompactRange(), change parameter "reduce_level" to "change_level". Users can compact all data to the last level if needed. By doing it, users can migrate the DB to options.level_compaction_dynamic_level_bytes=true.

Test Plan: Add a unit test for it.

Reviewers: yhchiang, anthony, kradhakrishnan, igor, rven

Reviewed By: rven

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D39099

Summary:
DBImpl::notifying_events_ is a internal counter in DBImpl which is
used to prevent DB close when DB is notifying events.  However, as
the current events all rely on either compaction or flush which
already have similar counters to prevent DB close, it is safe to
remove notifying_events_.

Test Plan:
listener_test
examples/compact_files_example

Reviewers: igor, anthony, kradhakrishnan, rven, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D39315

Summary: Broken by optimistic transaction diff.  (I only built 'release' not 'static_lib' when testing).

Test Plan: build

Reviewers: yhchiang, sdong, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D39219

Summary: Optimistic transactions supporting begin/commit/rollback semantics.  Currently relies on checking the memtable to determine if there are any collisions at commit time.  Not yet implemented would be a way of enuring the memtable has some minimum amount of history so that we won't fail to commit when the memtable is empty.  You should probably start with transaction.h to get an overview of what is currently supported.

Test Plan: Added a new test, but still need to look into stress testing.

Reviewers: yhchiang, igor, rven, sdong

Reviewed By: sdong

Subscribers: adamretter, MarkCallaghan, leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D33435

Summary:
For transactions, we are using the memtables to validate that there are no write conflicts.  But after flushing, we don't have any memtables, and transactions could fail to commit.  So we want to someone keep around some extra history to use for conflict checking.  In addition, we want to provide a way to increase the size of this history if too many transactions fail to commit.

After chatting with people, it seems like everyone prefers just using Memtables to store this history (instead of a separate history structure).  It seems like the best place for this is abstracted inside the memtable_list.  I decide to create a separate list in MemtableListVersion as using the same list complicated the flush/installalflushresults logic too much.

This diff adds a new parameter to control how much memtable history to keep around after flushing.  However, it sounds like people aren't too fond of adding new parameters.  So I am making the default size of flushed+not-flushed memtables be set to max_write_buffers.  This should not change the maximum amount of memory used, but make it more likely we're using closer the the limit.  (We are now postponing deleting flushed memtables until the max_write_buffer limit is reached).  So while we might use more memory on average, we are still obeying the limit set (and you could argue it's better to go ahead and use up memory now instead of waiting for a write stall to happen to test this limit).

However, if people are opposed to this default behavior, we can easily set it to 0 and require this parameter be set in order to use transactions.

Test Plan: Added a xfunc test to play around with setting different values of this parameter in all tests.  Added testing in memtablelist_test and planning on adding more testing here.

Reviewers: sdong, rven, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D37443

Summary:
Rename EventLoggerHelpers EventHelpers, as it's going to include
all event-related helper functions instead of EventLogger only stuffs.

Test Plan: make

Reviewers: sdong, rven, anthony

Reviewed By: anthony

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D39093

Summary: Move listeners from ColumnFamilyOptions to DBOptions

Test Plan:
listener_test
compact_files_test

Reviewers: rven, anthony, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D39087

Summary: Removed an unused private variable in db_impl.h

Test Plan: make db_test

Reviewers: sdong, anthony, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38925

Summary:
This patch fixes the following two bugs on logging file deletion.

1.  Previously, file deletion failure was only logged in INFO_LEVEL.
    This patch changes it to ERROR_LEVEL and does some code clean.

2.  EventLogger previously will always generate the same log on
    table file deletion even when file deletion is not successful.
    Now the resulting status of file deletion will also be logged.

Test Plan: make all check

Reviewers: sdong, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38817

Summary: Change the log-level of DB summary and options from INFO_LEVEL to WARN_LEVEL

Test Plan:
Use db_bench to verify the log level.

Sample output:
    2015/05/22-00:20:39.778064 7fff75b41300 [WARN] RocksDB version: 3.11.0
    2015/05/22-00:20:39.778095 7fff75b41300 [WARN] Git sha rocksdb_build_git_sha:7fee8775
    2015/05/22-00:20:39.778099 7fff75b41300 [WARN] Compile date May 22 2015
    2015/05/22-00:20:39.778101 7fff75b41300 [WARN] DB SUMMARY
    2015/05/22-00:20:39.778145 7fff75b41300 [WARN] SST files in /tmp/rocksdbtest-691931916/dbbench dir, Total Num: 0, files:
    2015/05/22-00:20:39.778148 7fff75b41300 [WARN] Write Ahead Log file in /tmp/rocksdbtest-691931916/dbbench:
    2015/05/22-00:20:39.778150 7fff75b41300 [WARN]          Options.error_if_exists: 0
    2015/05/22-00:20:39.778152 7fff75b41300 [WARN]        Options.create_if_missing: 1
    2015/05/22-00:20:39.778153 7fff75b41300 [WARN]          Options.paranoid_checks: 1

Reviewers: MarkCallaghan, igor, kradhakrishnan

Reviewed By: igor

Subscribers: sdong, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38835

Summary: Avoid logging under mutex in DBImpl::WriteLevel0TableForRecovery().

Test Plan: make all check

Reviewers: igor, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38823

Summary: Make DB::GetDbIdentity() be const function.

Test Plan: make db_test

Reviewers: igor, rven, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38745

Summary: Dump db stats in WARN level

Test Plan: run db_bench and verify the LOG

Reviewers: igor, MarkCallaghan

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38691

Summary:
sync_file_range is not always asyncronous and thus can block writes if we do this for WAL in the foreground thread. See more here: http://yoshinorimatsunobu.blogspot.com/2014/03/how-syncfilerange-really-works.html

Some users don't want us to call sync_file_range on WALs. Some other do.
Thus, I'm adding a separate option wal_bytes_per_sync to control calling
sync_file_range on WAL files. bytes_per_sync will apply only to table
files now.

Test Plan: no more sync_file_range for WAL as evidenced by strace

Reviewers: yhchiang, rven, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38253

Summary: As title. I spent some time thinking about it and I don't think there should be any issue with running manual compaction and flushes in parallel

Test Plan: make check works

Reviewers: rven, yhchiang, sdong

Reviewed By: yhchiang, sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38355

Summary: CompactRange() now is much more expensive for dynamic level base size as it goes through all the levels. Skip those not used levels between level 0 an base level.

Test Plan: Run all unit tests

Reviewers: yhchiang, rven, anthony, kradhakrishnan, igor

Reviewed By: igor

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D37125

Summary:
Example output:

    {"time_micros": 1431463794310521, "job": 353, "event": "table_file_creation", "file_number": 387, "file_size": 86937, "table_info": {"data_size": "81801", "index_size": "9751", "filter_size": "0", "raw_key_size": "23448", "raw_average_key_size": "24.000000", "raw_value_size": "990571", "raw_average_value_size": "1013.890481", "num_data_blocks": "245", "num_entries": "977", "filter_policy_name": "", "kDeletedKeys": "0"}}

Also fixed a bug where BuildTable() in recovery was passing Env::IOHigh argument into paranoid_checks_file parameter.

Test Plan: make check + check out the output in the log

Reviewers: sdong, rven, yhchiang

Reviewed By: yhchiang

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38343