Summary:

Test Plan:

Reviewers:

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Task ID: #

Blame Rev:

Summary:
 LevelDB should delete almost-new keys when a long-open snapshot exists.
The previous behavior is to keep all versions that were created after the
oldest open snapshot. This can lead to database size bloat for
high-update workloads when there are long-open snapshots and long-open
snapshot will be used for logical backup. By "almost new" I mean that the
key was updated more than once after the oldest snapshot.

If there were two snapshots with seq numbers s1 and s2 (s1 < s2), and if
we find two instances of the same key k1 that lie entirely within s1 and
s2 (i.e. s1 < k1 < s2), then the earlier version
of k1 can be safely deleted because that version is not visible in any snapshot.

Test Plan:
unit test attached
make clean check

Differential Revision: https://reviews.facebook.net/D6999

Summary: Added FBCODE like linting support to our codebase.

Test Plan: arc lint  lint's the code.

Reviewers: dhruba

Reviewed By: dhruba

CC: emayanke, leveldb

Differential Revision: https://reviews.facebook.net/D7041

Summary:
Print out status at the end of a compaction run. This helps in
debugging.

Test Plan: make clean check

Reviewers: sheki

Reviewed By: sheki

Differential Revision: https://reviews.facebook.net/D7035

Test Plan: make check

Reviewers: dhruba

Reviewed By: dhruba

CC: emayanke

Differential Revision: https://reviews.facebook.net/D6993

Summary:
When we expand the range of keys for a level 0 compaction, we
need to invoke ParentFilesInCompaction() only once for the
entire range of keys that is being compacted. We were invoking
it for each file that was being compacted, but this triggers
an assertion because each file's range were contiguous but
non-overlapping.

I renamed ParentFilesInCompaction to ParentRangeInCompaction
to adequately represent that it is the range-of-keys and
not individual files that we compact in a single compaction run.

Here is the assertion that is fixed by this patch.
db_test: db/version_set.cc:585: void leveldb::Version::ExtendOverlappingInputs(int, const leveldb::Slice&, const leveldb::Slice&, std::vector<leveldb::FileMetaData*, std::allocator<leveldb::FileMetaData*> >*, int): Assertion `user_cmp->Compare(flimit, user_begin) >= 0' failed.

Test Plan: make clean check OPT=-g

Reviewers: sheki

Reviewed By: sheki

CC: MarkCallaghan, emayanke, leveldb

Differential Revision: https://reviews.facebook.net/D6963

Summary:
On fast filesystems (e.g. /dev/shm and ext4), the flushing
of memstore to disk was fast and quick, and the background compaction
thread was not getting scheduled fast enough to delete obsolete
files before the db was closed. This caused the repair method
to pick up those files that were not part of the db and the unit
test was failing.

The fix is to enhance the unti test to run a compaction before
closing the database so that all files that are not part of the
database are truly deleted from the filesystem.

Test Plan: make c_test; ./c_test

Reviewers: chip, emayanke, sheki

Reviewed By: chip

CC: leveldb

Differential Revision: https://reviews.facebook.net/D6915

Summary:
It would appear our unit tests make use of code from ldb_cmd,
and don't always require a valid database handle.  D6855 was not aware
db_ could sometimes be NULL for such commands, and so it broke
reduce_levels_test.

This moves the check elsewhere to (at least) fix the 'ldb dump' case of
segfaulting when it couldn't open a database.

Test Plan: make check

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D6903

Summary:
Link statically against snappy, using the gvfs one for facebook
environments, and the bundled one otherwise.

In addition, fix a few minor segfaults in ldb when it couldn't open the
database, and update .gitignore to include a few other build artifacts.

Test Plan: make check

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D6855

Support taking a configurable number of  files from the same level to compact in a single compaction run.

Summary:
The compaction process takes some files from LevelK and
merges it into LevelK+1. The number of files it picks from
LevelK was capped such a way that the total amount of
data picked does not exceed the maxfilesize of that level.
This essentially meant that only one file from LevelK
is picked for a single compaction.

For bulkloads, we would like to take many many file from
LevelK and compact them using a single compaction run.

This patch introduces a option called the 'source_compaction_factor'
(similar to expanded_compaction_factor). It is a multiplier
that is multiplied by the maxfilesize of that level to arrive
at the limit that is used to throttle the number of source
files from LevelK.  For bulk loads, set source_compaction_factor
to a very high number so that multiple files from the same
level are picked for compaction in a single compaction.

The default value of source_compaction_factor is 1, so that
we can keep backward compatibilty with existing compaction semantics.

Test Plan: make clean check

Reviewers: emayanke, sheki

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D6867

Summary:
This option is needed for fast bulk uploads. The goal is to load
all the data into files in L0 without any interference from
background compactions.

Test Plan: make clean check

Reviewers: sheki

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D6849

Summary:
The method Finalize() recomputes the compaction score of each
level and then sorts these score from largest to smallest. The
idea is that the level with the largest compaction score will
be a better candidate for compaction.  There are usually very
few levels, and a bubble sort code was used to sort these
compaction scores. There existed a bug in the sorting code that
skipped looking at the score for the n-1 level. This meant that
even if the compaction score of the n-1 level is large, it will
not be picked for compaction.

This patch fixes the bug and also introduces "asserts" in the
code to detect any possible inconsistencies caused by future bugs.

This bug existed in the very first code change that introduced
multi-threaded compaction to the leveldb code. That version of
code was committed on Oct 19th via
https://github.com/facebook/leveldb/commit/1ca0584345af85d2dccc434f451218119626d36e

Test Plan: make clean check OPT=-g

Reviewers: emayanke, sheki, MarkCallaghan

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D6837

Summary:
make check OPT=-g fails with the following assert.
==== Test DBTest.ApproximateSizes
db_test: db/version_set.cc:765: void leveldb::VersionSet::Builder::CheckConsistencyForDeletes(leveldb::VersionEdit*, int, int): Assertion `found' failed.

The assertion was that file #7 that was being deleted did not
preexists, but actualy it did pre-exist as shown in the manifest
dump shows below. The bug was that we did not check for file
existance at the same level.

*************************Edit[0] = VersionEdit {
  Comparator: leveldb.BytewiseComparator
}

*************************Edit[1] = VersionEdit {
  LogNumber: 8
  PrevLogNumber: 0
  NextFile: 9
  LastSeq: 80
  AddFile: 0 7 8005319 'key000000' @ 1 : 1 .. 'key000079' @ 80 : 1
}

*************************Edit[2] = VersionEdit {
  LogNumber: 8
  PrevLogNumber: 0
  NextFile: 13
  LastSeq: 80
  CompactPointer: 0 'key000079' @ 80 : 1
  DeleteFile: 0 7
  AddFile: 1 9 2101425 'key000000' @ 1 : 1 .. 'key000020' @ 21 : 1
  AddFile: 1 10 2101425 'key000021' @ 22 : 1 .. 'key000041' @ 42 : 1
  AddFile: 1 11 2101425 'key000042' @ 43 : 1 .. 'key000062' @ 63 : 1
  AddFile: 1 12 1701165 'key000063' @ 64 : 1 .. 'key000079' @ 80 : 1
}

Test Plan:

Reviewers:

CC:

Task ID: #

Blame Rev:

Summary:
Fix compilation error while compiling with OPT=-g

Test Plan:
make clean check OPT=-g

Reviewers:

CC:

Task ID: #

Blame Rev:

7889e094

Summary:
Fix compilation error introduced by previous commit
7889e094

Test Plan:
make clean check

Summary:
The manifest file contains a series of edits. If the verbose
option is switched on, then print each individual edit in the
manifest file. This helps in debugging.

Test Plan: make clean manifest_dump

Reviewers: emayanke, sheki

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D6807

Summary:
StringStream.clear() does not clear the stream. It sets some flags.
Who knew? Fixing that is not printing the stuff again and again.

Test Plan: ran it on a local db

Reviewers: dhruba, emayanke

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D6795

Summary: The new function MinLevelToCompress in db_test.cc was incomplete. It needs to tell the calling function-TEST whether the test has to be skipped or not

Test Plan: make all;./db_test

Reviewers: dhruba, heyongqiang

Reviewed By: dhruba

CC: sheki

Differential Revision: https://reviews.facebook.net/D6771

Summary:
Add option to read WAL and print a summary for each record.
facebook task => #1885013

E.G. Output :
./ldb dump_wal --walfile=/tmp/leveldbtest-5907/dbbench/026122.log --header
Sequence,Count,ByteSize
49981,1,100033
49981,1,100033
49982,1,100033
49981,1,100033
49982,1,100033
49983,1,100033
49981,1,100033
49982,1,100033
49983,1,100033
49984,1,100033
49981,1,100033
49982,1,100033

Test Plan:
Works run
./ldb read_wal --wal-file=/tmp/leveldbtest-5907/dbbench/000078.log --header

Reviewers: dhruba, heyongqiang

Reviewed By: dhruba

CC: emayanke, leveldb, zshao

Differential Revision: https://reviews.facebook.net/D6675

Summary:
The manifest file contains a series of edits. If the verbose
option is switched on, then print each individual edit in the
manifest file. This helps in debugging.

Test Plan: make clean manifest_dump

Reviewers: emayanke, sheki

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D6807

Summary:
StringStream.clear() does not clear the stream. It sets some flags.
Who knew? Fixing that is not printing the stuff again and again.

Test Plan: ran it on a local db

Reviewers: dhruba, emayanke

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D6795

Summary:
dbstress has an option to reopen the database. Make it such that the
previous handle is not closed before we reopen, this simulates a
situation similar to a process crash.

Added new api to DMImpl to remove the lock file.

Test Plan: run db_stress

Reviewers: emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D6777

Summary: The new function MinLevelToCompress in db_test.cc was incomplete. It needs to tell the calling function-TEST whether the test has to be skipped or not

Test Plan: make all;./db_test

Reviewers: dhruba, heyongqiang

Reviewed By: dhruba

CC: sheki

Differential Revision: https://reviews.facebook.net/D6771

Summary:
Add option to read WAL and print a summary for each record.
facebook task => #1885013

E.G. Output :
./ldb dump_wal --walfile=/tmp/leveldbtest-5907/dbbench/026122.log --header
Sequence,Count,ByteSize
49981,1,100033
49981,1,100033
49982,1,100033
49981,1,100033
49982,1,100033
49983,1,100033
49981,1,100033
49982,1,100033
49983,1,100033
49984,1,100033
49981,1,100033
49982,1,100033

Test Plan:
Works run
./ldb read_wal --wal-file=/tmp/leveldbtest-5907/dbbench/000078.log --header

Reviewers: dhruba, heyongqiang

Reviewed By: dhruba

CC: emayanke, leveldb, zshao

Differential Revision: https://reviews.facebook.net/D6675

Summary:
Create more than one background compaction thread if specified.
This code peice is similar to what exists in db_bench.

Test Plan: make check

Differential Revision: https://reviews.facebook.net/D6753

Conflicts:
	db/db_impl.h

Summary:
The value specified in max_grandparent_overlap_factor is used to
limit the file size in a compaction run. This patch makes it
configurable when using db_bench.

Test Plan: make clean db_bench

Reviewers: MarkCallaghan, heyongqiang

Reviewed By: heyongqiang

CC: leveldb

Differential Revision: https://reviews.facebook.net/D6729

Summary:

Test Plan:

Reviewers:

CC:

Task ID: #

Blame Rev:

Summary:
The fbcode compilation was always switching on msse by default.
This patch keeps the same behaviour but allows the compilation
process to switch off msse if needed.

If one does not want to use sse, then do the following:
export USE_SSE=0
make clean all

Test Plan: make clean all

Reviewers: heyongqiang

Reviewed By: heyongqiang

CC: leveldb

Differential Revision: https://reviews.facebook.net/D6717

Summary:
There are applications that operate on multiple leveldb instances.
These applications will like to pass in an opaque type for each
leveldb instance and this type should be passed back to the application
with every invocation of the CompactionFilter api.

Test Plan: Enehanced unit test for opaque parameter to CompactionFilter.

Reviewers: heyongqiang

Reviewed By: heyongqiang

CC: MarkCallaghan, sheki, emayanke

Differential Revision: https://reviews.facebook.net/D6711

Summary:
Compilation used to fail with the error:
db/version_set.cc:1773: error: ‘number_of_files_to_sort_’ is not a member of ‘leveldb::VersionSet’

I created a new method called CheckConsistencyForDeletes() so that
all the high cost checking is done only when OPT=-g is specified.

I also fixed a bug in PickCompactionBySize that was triggered when
OPT=-g was switched on. The base_index in the compaction record
was not set correctly.

Test Plan: make check OPT=-g

Differential Revision: https://reviews.facebook.net/D6687

Summary:
The db_bench utility was broken in 1.5.4.fb because of a
signed-unsigned comparision.

The static variable FLAGS_min_level_to_compress was recently
changed from int to 'unsigned in' but it is initilized to a
nagative value -1.

The segfault is of this type:
Program received signal SIGSEGV, Segmentation fault.
Open (this=0x7fffffffdee0) at db/db_bench.cc:939
939	db/db_bench.cc: No such file or directory.
(gdb) where

Test Plan: run db_bench with no options.

Reviewers: heyongqiang

Reviewed By: heyongqiang

CC: MarkCallaghan, emayanke, sheki

Differential Revision: https://reviews.facebook.net/D6663

Introducing "database reopens" into the stress test. Database will reopen after a specified number of iterations (configurable) of each thread when they will wait for the databse to reopen.

Summary: FLAGS_reopen (configurable) specifies the number of times the databse is to be reopened. FLAGS_ops_per_thread is divided into points based on that reopen field. At these points all threads come together to wait for the databse to reopen. Each thread "votes" for the database to reopen and when all have voted, the database reopens.

Test Plan: make all;./db_stress

Reviewers: dhruba, MarkCallaghan, sheki, asad, heyongqiang

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D6627

Summary:
I changed the reduce_num_levels logic to avoid "compactRange()" call if the current number of levels in use (levels that contain files) is smaller than the new num of levels.
And that change breaks the assert in reduce_levels_test

Test Plan: run reduce_levels_test

Reviewers: dhruba, MarkCallaghan

Reviewed By: dhruba

CC: emayanke, sheki

Differential Revision: https://reviews.facebook.net/D6651

Summary:
make clean check OPT=-g fails
leveldb::DBStatistics::getTickerCount(leveldb::Tickers)’:
./db/db_statistics.h:34: error: ‘MAX_NO_TICKERS’ was not declared in this scope
util/ldb_cmd.cc:255: warning: left shift count >= width of type

Test Plan:
make clean check OPT=-g

Reviewers:

CC:

Task ID: #

Blame Rev:

Summary: Record BloomFliter hits and drop off reasons during compaction.

Test Plan: Unit tests work.

Reviewers: dhruba, heyongqiang

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D6591

Summary:
disable size compaction in ldb reduce_levels, this will avoid compactions rather than the manual comapction,

added --compression=none|snappy|zlib|bzip2 and --file_size= per-file size to ldb reduce_levels command

Test Plan: run ldb

Reviewers: dhruba, MarkCallaghan

Reviewed By: dhruba

CC: sheki, emayanke

Differential Revision: https://reviews.facebook.net/D6597

Summary:
Preparing for new release 1.5.4.fb

Test Plan:

Reviewers:

CC:

Task ID: #

Blame Rev: