Commit Graph

920 Commits

Author SHA1 Message Date
Igor Canadi
6de1b5b83e Merge branch 'master' into columnfamilies 2014-01-02 04:18:07 -08:00
Igor Canadi
b60c14f6ee Support multi-threaded DisableFileDeletions() and EnableFileDeletions()
Summary:
We don't want two threads to clash if they concurrently call DisableFileDeletions() and EnableFileDeletions(). I'm adding a counter that will enable file deletions only after all DisableFileDeletions() calls have been negated with EnableFileDeletions().

However, we also don't want to break the old behavior, so I added a parameter force to EnableFileDeletions(). If force is true, we will still enable file deletions after every call to EnableFileDeletions(), which is what is happening now.

Test Plan: make check

Reviewers: dhruba, haobo, sanketh

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14781
2014-01-02 03:33:42 -08:00
kailiu
f1cec73a76 Merge branch 'master' into performance
Conflicts:
	db/db_impl.cc
	db/db_test.cc
	db/memtable.cc
	db/version_set.cc
	include/rocksdb/statistics.h
2013-12-27 12:23:17 -08:00
kailiu
079a21ba99 Fix the unused variable warning message in mac os 2013-12-26 15:12:30 -08:00
Siying Dong
abaf26266d [RocksDB] [Performance Branch] Some Changes to PlainTable format
Summary:
Some changes to PlainTable format:
(1) support variable key length
(2) use user defined slice transformer to extract prefixes
(3) Run some test cases against PlainTable in db_test and table_test

Test Plan: test db_test

Reviewers: haobo, kailiu

CC: dhruba, igor, leveldb, nkg-

Differential Revision: https://reviews.facebook.net/D14457
2013-12-20 12:08:35 -08:00
Igor Canadi
9385a5247e [RocksDB] [Column Family] Interface proposal
Summary:
<This diff is for Column Family branch>

Sharing some of the work I've done so far. This diff compiles and passes the tests.

The biggest change is in options.h - I broke down Options into two parts - DBOptions and ColumnFamilyOptions. DBOptions is DB-specific (env, create_if_missing, block_cache, etc.) and ColumnFamilyOptions is column family-specific (all compaction options, compresion options, etc.). Note that this does not break backwards compatibility at all.

Further, I created DBWithColumnFamily which inherits DB interface and adds new functions with column family support. Clients can transparently switch to DBWithColumnFamily and it will not break their backwards compatibility.
There are few methods worth checking out: ListColumnFamilies(), MultiNewIterator(), MultiGet() and GetSnapshot(). [GetSnapshot() returns the snapshot across all column families for now - I think that's what we agreed on]

Finally, I made small changes to WriteBatch so we are able to atomically insert data across column families.

Please provide feedback.

Test Plan: make check works, the code is backward compatible

Reviewers: dhruba, haobo, sdong, kailiu, emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14445
2013-12-18 13:08:22 -08:00
kailiu
0cd1521af5 Completely remove argv_ since no one use it
There are still warning in some other environment, just move that useless variable `argv_`
2013-12-12 16:36:38 -08:00
kailiu
0e24f97b9f Revert last commit and add "unused" attribute to suppress warning 2013-12-12 15:40:44 -08:00
kailiu
bc9b488e92 fix a warning in db_test when running make release 2013-12-12 15:35:02 -08:00
Igor Canadi
fb9fce4fc3 [RocksDB] BackupableDB
Summary:
In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you.
Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes.

There are multiple things you can configure:
1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like.
2. sync - if true, it *guarantees* backup consistency on machine reboot
3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files.
4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup.
5. More things you can find in BackupableDBOptions

Here is the directory structure I use:

   backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot
               0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files
               files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file
               files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files

All the files are ref counted and deleted immediatelly when they get out of scope.

Some other stuff in this diff:
1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do.
2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB.

Test Plan:
I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff.

Also, `make asan_check`

Reviewers: dhruba, haobo, emayanke

Reviewed By: dhruba

CC: leveldb, haobo

Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 14:06:52 -08:00
kailiu
551e9428ce Merge branch 'master' into performance 2013-12-06 14:15:42 -08:00
Mayank Agarwal
92e8316118 Make GetDbIdentity pure virtual and also implement it for StackableDB, DBWithTTL
Summary: As title

Test Plan: make clean and make

Reviewers: igor

Reviewed By: igor

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14469
2013-12-05 12:02:31 -08:00
Mayank Agarwal
18802689b8 Make an API to get database identity from the IDENTITY file
Summary: This would enable rocksdb users to get the db identity without depending on implementation details(storing that in IDENTITY file)

Test Plan: db/db_test (has identity checks)

Reviewers: dhruba, haobo, igor, kailiu

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14463
2013-12-04 22:39:17 -08:00
Igor Canadi
eb12e47e0e Killing Transform Rep
Summary:
Let's get rid of TransformRep and it's children. We have confirmed that HashSkipListRep works better with multifeed, so there is no benefit to keeping this around.

This diff is mostly just deleting references to obsoleted functions. I also have a diff for fbcode that we'll need to push when we switch to new release.

I had to expose HashSkipListRepFactory in the client header files because db_impl.cc needs access to GetTransform() function for SanitizeOptions.

Test Plan: make check

Reviewers: dhruba, haobo, kailiu, sdong

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14397
2013-12-03 12:42:15 -08:00
Igor Canadi
35ddf18367 Don't do compression tests if we don't have compression libs
Summary: These tests fail if compression libraries are not installed.

Test Plan: Manually disabled snappy, observed tests not ran.

Reviewers: dhruba, kailiu

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14379
2013-11-27 13:32:56 -08:00
Kai Liu
1966b63137 Merge branch 'master' into perf 2013-11-27 11:47:40 -08:00
Igor Canadi
3ce3658411 DB::GetOptions()
Summary: We need access to options for BackupableDB

Test Plan: make check

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb, reconnect.grayhat

Differential Revision: https://reviews.facebook.net/D14331
2013-11-25 15:51:50 -08:00
Igor Canadi
11c26bd4a4 [RocksDB] Interface changes required for BackupableDB
Summary: This is part of https://reviews.facebook.net/D14295 -- smaller diff that is easier to review

Test Plan: make asan_check

Reviewers: dhruba, haobo, emayanke

Reviewed By: emayanke

CC: leveldb, kailiu, reconnect.grayhat

Differential Revision: https://reviews.facebook.net/D14301
2013-11-25 12:39:23 -08:00
Siying Dong
3e35aa6412 Revert "Allow users to profile a query and see bottleneck of the query"
This reverts commit 3d8ac31d71.
2013-11-21 17:40:39 -08:00
Siying Dong
b135d01e7b Allow users to profile a query and see bottleneck of the query
Summary:
Provide a framework to profile a query in detail to figure out latency bottleneck. Currently, in Get(), Put() and iterators, 2-3 simple timing is used. We can easily add more profile counters to the framework later.

Test Plan: Enable this profiling in seveal existing tests.

Reviewers: haobo, dhruba, kailiu, emayanke, vamsi, igor

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14001

Conflicts:
	table/merger.cc
2013-11-21 17:39:19 -08:00
Siying Dong
3d8ac31d71 Allow users to profile a query and see bottleneck of the query
Summary:
Provide a framework to profile a query in detail to figure out latency bottleneck. Currently, in Get(), Put() and iterators, 2-3 simple timing is used. We can easily add more profile counters to the framework later.

Test Plan: Enable this profiling in seveal existing tests.

Reviewers: haobo, dhruba, kailiu, emayanke, vamsi, igor

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14001
2013-11-21 16:29:57 -08:00
Igor Canadi
fc61428288 Include <unistd.h> in db_test
Summary: This is the only compile issue in Ubuntu. It might be better to include <unistd.h> only in env_posix and add Truncate function to Env, but since we use truncate only in db_test, I don't think it makes much sense.

Test Plan: Rocksdb now compiles on Ubuntu!

Reviewers: dhruba, kailiu

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14127
2013-11-17 21:58:16 -08:00
Igor Canadi
de9ce7d439 Upgrading compiler to gcc4.8.1
Summary:
Finally did it - the trick was in using --dynamic-linker option. This is first step to running ASAN.

All of our code seems to compile just fine on 4.8.1. However, I still left fbcode.471.sh in the 'build_tools/' just in case.

Test Plan: make clean; make

Reviewers: dhruba, haobo, kailiu, emayanke, sdong

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14109
2013-11-17 13:52:55 -08:00
kailiu
97d8e573a6 make util/env_posix.cc work under mac
Summary: This diff invoves some more complicated issues in the posix environment.

Test Plan: works under mac os. will need to verify dev box.

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14061
2013-11-16 23:44:39 -08:00
Kai Liu
88ba331c1a Add the index/filter block cache
Summary: This diff leverage the existing block cache and extend it to cache index/filter block.

Test Plan:
Added new tests in db_test and table_test

The correctness is checked by:

1. make check
2. make valgrind_check

Performance is test by:

1. 10 times of build_tools/regression_build_test.sh on two versions of rocksdb before/after the code change. Test results suggests no significant difference between them. For the two key operatons `overwrite` and `readrandom`, the average iops are both 20k and ~260k, with very small variance).
2. db_stress.

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb, haobo, xjin

Differential Revision: https://reviews.facebook.net/D13167
2013-11-12 22:46:51 -08:00
kailiu
21587760b9 Fixing the warning messages captured under mac os # Consider using git commit -m 'One line title' && arc diff. # You will save time by running lint and unit in the background.
Summary: The work to make sure mac os compiles rocksdb is not completed yet. But at least we can start cleaning some warnings captured only by g++ from mac os..

Test Plan: ran make in mac os

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14049
2013-11-12 20:05:28 -08:00
Igor Canadi
1510339e52 Speed up FindObsoleteFiles
Summary:
Here's one solution we discussed on speeding up FindObsoleteFiles. Keep a set of all files in DBImpl and update the set every time we create a file. I probably missed few other spots where we create a file.

It might speed things up a bit, but makes code uglier. I don't really like it.

Much better approach would be to abstract all file handling to a separate class. Think of it as layer between DBImpl and Env. Having a separate class deal with file namings and deletion would benefit both code cleanliness (especially with huge DBImpl) and speed things up. It will take a huge effort to do this, though.

Let's discuss offline today.

Test Plan: Ran ./db_stress, verified that files are getting deleted

Reviewers: dhruba, haobo, kailiu, emayanke

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D13827
2013-11-08 15:23:46 -08:00
Igor Canadi
dd218bbc88 Forgot to change interface everywhere
Summary: Changed the name and interface for creating HashSkipListRep. Forgot to change it in db_test.

Test Plan: make db_test

Reviewers: haobo

Reviewed By: haobo

Differential Revision: https://reviews.facebook.net/D13965
2013-11-08 12:23:12 -08:00
shamdor
c2be2cba04 WAL log retention policy based on archive size.
Summary:
Archive cleaning will still happen every WAL_ttl seconds
but archived logs will be deleted only if archive size
is greater then a WAL_size_limit value.
Empty archived logs will be deleted evety WAL_ttl.

Test Plan:
1. Unit tests pass.
2. Benchmark.

Reviewers: emayanke, dhruba, haobo, sdong, kailiu, igor

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13869
2013-11-06 18:46:28 -08:00
Igor Canadi
be96f2498e TransformRep - use array instead of unordered_map
Summary:
I'm sending this diff together with https://reviews.facebook.net/D13881 because it didn't allow me to send only the array one.

Here I also replaced unordered_map with just an array of shared_ptrs. This elminated all the locks.

I will run the new benchmark and post the results here.

Test Plan: db_test

Reviewers: dhruba, haobo

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13893
2013-11-06 11:55:43 -08:00
Dhruba Borthakur
39190588e1 Fix failure in rocksdb unit test CompressedCache
Summary:
The problem was that there was only a single key-value in a block
and its compressibility was less than 88%. Rocksdb refuses to
compress a block unless its compresses to lesser than 88% of its
original size. If a block is not compressed, it does nto get inserted
into the compressed block cache.

Create the test data so that multiple records fit into the same
data block. This increases the compressibility of these data block.

Test Plan: ./db_test

Reviewers: kailiu, haobo

Reviewed By: kailiu

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13905
2013-11-05 16:11:34 -08:00
Dhruba Borthakur
7845fd9db9 Fixed valgrind error in DBTest.CompressedCache
Summary:
Fixed valgrind error in DBTest.CompressedCache.
This fixes the valgrind error (thanks to Haobo). I am still trying to reproduce the test-failure case deterministically.

Test Plan: db_test

Reviewers: haobo

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13899
2013-11-05 11:12:39 -08:00
Mayank Agarwal
f837f5b1c9 Making the transaction log iterator more robust
Summary:
strict essentially means that we MUST find the startsequence. Thus we should return if starteSequence is not found in the first file in case strict is set. This will take care of ending the iterator in case of permanent gaps due to corruptions in the log files
Also created NextImpl function that will have internal variable to distinguish whether Next is being called from StartSequence or by application.
Set NotFoudn::gaps status to give an indication of gaps happeneing.
Polished the inline documentation at various places

Test Plan:
* db_repl_stress test
* db_test relating to transaction log iterator
* fbcode/wormhole/rocksdb/rocks_log_iterator
* sigma production machine sigmafio032.prn1

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13689
2013-11-04 20:49:03 -08:00
Dhruba Borthakur
b4ad5e89ae Implement a compressed block cache.
Summary:
Rocksdb can now support a uncompressed block cache, or a compressed
block cache or both. Lookups first look for a block in the
uncompressed cache, if it is not found only then it is looked up
in the compressed cache. If it is found in the compressed cache,
then it is uncompressed and inserted into the uncompressed cache.

It is possible that the same block resides in the compressed cache
as well as the uncompressed cache at the same time. Both caches
have their own individual LRU policy.

Test Plan: Unit test case attached.

Reviewers: kailiu, sdong, haobo, leveldb

Reviewed By: haobo

CC: xjin, haobo

Differential Revision: https://reviews.facebook.net/D12675
2013-11-01 14:31:35 -07:00
Haobo Xu
8cbe5bb56b [RocksDB] Add OnCompactionStart to CompactionFilter class
Summary: This is to give application compaction filter a chance to access context information of a specific compaction run. For example, depending on whether a compaction goes through all data files, the application could do things differently.

Test Plan: make check

Reviewers: dhruba, kailiu, sdong

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13683
2013-10-31 13:36:43 -07:00
Naman Gupta
b4fab3be2a Merge branch 'master' of github.com:facebook/rocksdb into inplace 2013-10-31 11:51:03 -07:00
Naman Gupta
fe25070242 In-place updates for equal keys and similar sized values
Summary:
Currently for each put, a fresh memory is allocated, and a new entry is added to the memtable with a new sequence number irrespective of whether the key already exists in the memtable. This diff is an attempt to update the value inplace for existing keys. It currently handles a very simple case:
1. Key already exists in the current memtable. Does not inplace update values in immutable memtable or snapshot
2. Latest value type is a 'put' ie kTypeValue
3. New value size is less than existing value, to avoid reallocating memory

TODO: For a put of an existing key, deallocate memory take by values, for other value types till a kTypeValue is found, ie. remove kTypeMerge.
TODO: Update the transaction log, to allow consistent reload of the memtable.

Test Plan: Added a unit test verifying the inplace update. But some other unit tests broken due to invalid sequence number checks. WIll fix them next.

Reviewers: xinyaohu, sumeet, haobo, dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12423

Automatic commit by arc
2013-10-31 11:27:12 -07:00
Siying Dong
d4eec30ed0 Make "Table" pluggable
Summary: This patch makes Table and TableBuilder a abstract class and make all the implementation of the current table into BlockedBasedTable and BlockedBasedTable Builder.

Test Plan: Make db_test.cc to work with block based table. Add a new test simple_table_db_test.cc where a different simple table format is implemented.

Reviewers: dhruba, haobo, kailiu, emayanke, vamsi

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13521
2013-10-28 17:54:09 -07:00
Igor Canadi
100fa8e013 If a Put fails, fail all other puts
Summary:
When a Put fails, it can leave database in a messy state. We don't want to pretend that everything is OK when it may not be. We fail every write following the failed one.

I added checks for corruption to DBImpl::Write(). Is there anywhere else I need to add them?

Test Plan: Corruption unit test.

Reviewers: dhruba, haobo, kailiu

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13671
2013-10-28 12:36:02 -07:00
Mayank Agarwal
56305221c4 Unify DeleteFile and DeleteWalFiles
Summary:
This is to simplify rocksdb public APIs and improve the code quality.
Created an additional parameter to ParseFileName for log sub type and improved the code for deleting a wal file.
Wrote exhaustive unit-tests in delete_file_test
Unification of other redundant APIs can be taken up in a separate diff

Test Plan: Expanded delete_file test

Reviewers: dhruba, haobo, kailiu, sdong

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13647
2013-10-25 08:32:14 -07:00
Mayank Agarwal
9b50106f9a Dbid feature
Summary:
Create a new type of file on startup if it doesn't already exist called DBID.
This will store a unique number generated from boost library's uuid header file.
The use-case is to identify the case of a db losing all its data and coming back up either empty or from an image(backup/live replica's recovery)
the key point to note is that DBID is not stored in a backup or db snapshot
It's preferable to use Boost for uuid because:
1) A non-standard way of generating uuid is not good
2) /proc/sys/kernel/random/uuid generates a uuid but only on linux environments and the solution would not be clean
3) c++ doesn't have any direct way to get a uuid
4) Boost is a very good library that was already having linkage in rocksdb from third-party
Note: I had to update the TOOLCHAIN_REV in build files to get latest verison of boost from third-party as the older version had a bug.
I had to put Wno-uninitialized in Makefile because boost-1.51 has an unitialized variable and rocksdb would not comiple otherwise. Latet open-source for boost is 1.54 but is not there in third-party. I have notified the concerned people in fbcode about it.
@kailiu : While releasing to third-party, an additional dependency will need to be created for boost in TARGETS file. I can help identify.

Test Plan:
Expand db_test to test 2 cases
1) Restarting db with Id file present - verify that no change to Id
2)Restarting db with Id file deleted - verify that a different Id is there after reopen
Also run make all check

Reviewers: dhruba, haobo, kailiu, sdong

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13587
2013-10-22 12:23:34 -07:00
Siying Dong
65428b0c0a Fix Bug: iterator.Prev() or iterator.SeekToLast() might return the first element instead of the correct one
Summary:
Recent patch https://reviews.facebook.net/D11865 introduced a regression bug:

DBIter::FindPrevUserEntry(), which is called by DBIter::Prev() (and also implicitly if calling iterator.SeekToLast())  might do issue a seek when having skipped too many entries. If the skipped entry just before the seek() is a delete, the saved key is erased so that it seeks to the front, so Prev() would return the first element.

This patch fixes the bug by not doing seek() in DBIter::FindNextUserEntry() if saved key has been erased.

Test Plan: Add a test DBTest.IterPrevMaxSkip which would fail without the patch and would pass with the change.

Reviewers: dhruba, xjin, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13557
2013-10-17 18:33:18 -07:00
Siying Dong
9edda37027 Universal Compaction to Have a Size Percentage Threshold To Decide Whether to Compress
Summary:
This patch adds a option for universal compaction to allow us to only compress output files if the files compacted previously did not yet reach a specified ratio, to save CPU costs in some cases.

Compression is always skipped for flushing. This is because the size information is not easy to evaluate for flushing case. We can improve it later.

Test Plan:
add test
DBTest.UniversalCompactionCompressRatio1 and DBTest.UniversalCompactionCompressRatio12

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13467
2013-10-17 13:33:39 -07:00
Dhruba Borthakur
9cd221094c Add appropriate LICENSE and Copyright message.
Summary:
Add appropriate LICENSE and Copyright message.

Test Plan:
make check

Reviewers:

CC:

Task ID: #

Blame Rev:
2013-10-16 17:48:41 -07:00
Siying Dong
073cbfc8f0 Enable background flush thread by default and fix issues related to it
Summary:
Enable background flush thread in this patch and fix unit tests with:
(1) After background flush, schedule a background compaction if condition satisfied;
(2) Fix a bug that if universal compaction is enabled and number of levels are set to be 0, compaction will not be automatically triggered
(3) Fix unit tests to wait for compaction to finish instead of flush, before checking the compaction results.

Test Plan: pass all unit tests

Reviewers: haobo, xjin, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13461
2013-10-16 13:32:53 -07:00
Mayank Agarwal
fe3713961e Features in Transaction log iterator
Summary:
* Logstore requests a valid change of reutrning an empty iterator and not an error in case of no log files.
* Changed the code to return the writebatch containing the sequence number requested from GetupdatesSince even if it lies in the middle. Earlier we used to return the next writebatch,. This also allows me oto guarantee that no files played upon by the iterator are redundant. I mean the starting log file has at least a sequence number >= the sequence number requested form GetupdatesSince.
* Cleaned up redundant logic in Iterator::Next and made a new function SeekToStartSequence for greater readability and maintainibilty.
* Modified a test in db_test accordingly
Please check the logic carefully and suggest improvements. I have a separate patch out for more improvements like restricting reader to read till written sequences.

Test Plan:
* transaction log iterator tests in db_test,
* db_repl_stress.
* rocks_log_iterator_test in fbcode/wormhole/rocksdb/test - 2 tests thriving on hacks till now can get simplified
* testing on the shadow setup for sigma with replication

Reviewers: dhruba, haobo, kailiu, sdong

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13437
2013-10-14 18:16:21 -07:00
Siying Dong
88f2f89068 Change Function names from Compaction->Flush When they really mean Flush
Summary: When I debug the unit test failures when enabling background flush thread, I feel the function names can be made clearer for people to understand. Also, if the names are fixed, in many places, some tests' bugs are obvious (and some of those tests are failing). This patch is to clean it up for future maintenance.

Test Plan: Run test suites.

Reviewers: haobo, dhruba, xjin

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13431
2013-10-14 15:12:15 -07:00
Mayank Agarwal
a8b4a69de0 Fixing error in ParseFileName causing DestroyDB to fail on archive directory
Summary:
This careless error was causing ASSERT_OK(DestroyDB) to fail in db_test.
Basically .. was being returned as a child of db/archive and ParseFileName returned false on that,
but 'type' was set to LogFile from earlier and not reset. The return of ParseFileName was not being checked to delete the log file or not.

Test Plan: make all check

Reviewers: dhruba, haobo, xjin, kailiu, nkg-

Reviewed By: nkg-

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13413
2013-10-10 18:18:31 -07:00
Naman Gupta
cbf4a06427 Add option for storing transaction logs in a separate dir
Summary: In some cases, you might not want to store the data log (write ahead log) files in the same dir as the sst files. An example use case is leaf, which stores sst files in tmpfs. And would like to save the log files in a separate dir (disk) to save memory.

Test Plan: make all. Ran db_test test. A few test failing. P2785018. If you guys don't see an obvious problem with the code, maybe somebody from the rocksdb team could help me debug the issue here. Running this on leaf worked well. I could see logs stored on disk, and deleted appropriately after compactions. Obviously this is only one set of options. The unit tests cover different options. Seems like I'm missing some edge cases.

Reviewers: dhruba, haobo, leveldb

CC: xinyaohu, sumeet

Differential Revision: https://reviews.facebook.net/D13239
2013-10-08 17:40:27 -07:00
Naman Gupta
116071411b Make db_test more robust
Summary: While working on D13239, I noticed that the same options are not used for opening and destroying at db. So adding that. Also added asserts for successful DestroyDB calls.

Test Plan: Ran unit tests. Atleast 1 unit test is failing. They failures are a result of some past logic change. I'm not really planning to fix those. But I would like to check this in. And hopefully the respective unit test owners can fix the broken tests

Reviewers: leveldb, haobo

CC: xinyaohu, sumeet, dhruba

Differential Revision: https://reviews.facebook.net/D13329
2013-10-08 13:19:31 -07:00
Dhruba Borthakur
1a8c1b0817 Unit test failure in DBTest.NumImmutableMemTable.
Summary:
Previous patch introduced a unit test failure in
DBTest.NumImmutableMemTable because of change in property names.

Test Plan:

Reviewers:

CC:

Task ID: #

Blame Rev:
2013-10-06 01:12:02 -07:00
Dhruba Borthakur
4463b11cad Migrate names of properties from 'leveldb' prefix to 'rocksdb' prefix.
Summary: Migrate names of properties from 'leveldb' prefix to 'rocksdb' prefix.

Test Plan: make check

Reviewers: emayanke, haobo

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13311
2013-10-06 00:14:26 -07:00
Haobo Xu
bf89edf78b [RocksDB] Added a property "leveldb.num-immutable-mem-table" so that Flush can be called without blocking, and application still has a way to check when it's done also without blocking.
Summary: as title

Test Plan: DBTest.NumImmutableMemTable

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13305
2013-10-05 11:54:08 -07:00
Dhruba Borthakur
a143ef9b38 Change namespace from leveldb to rocksdb
Summary:
Change namespace from leveldb to rocksdb. This allows a single
application to link in open-source leveldb code as well as
rocksdb code into the same process.

Test Plan: compile rocksdb

Reviewers: emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13287
2013-10-04 11:59:26 -07:00
Mayank Agarwal
854d236361 Add backward compatible option in GetLiveFiles to choose whether to not Flush first
Summary:
As explained in comments in GetLiveFiles in db.h, this option will cause flush to be skipped in GetLiveFiles because some use-cases use GetSortedWalFiles after GetLiveFiles to generate more complete snapshots.
Using GetSortedWalFiles after GetLiveFiles allows us to not Flush in GetLiveFiles first because wals have everything.
Note: file deletions will be disabled before calling GLF or GSWF so live logs will not move to archive logs or get delted.
Note: Manifest file is truncated to a proper value in GLF, so it will always reply from the proper wal files on a restart

Test Plan: make

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13257
2013-10-04 10:20:10 -07:00
Xing Jin
658a3ce2fa Fix SIGSEGV issue in universal compaction
Summary:
We saw SIGSEGV when set options.num_levels=1 in universal compaction
style. Dug into this issue for a while, and finally found the root cause (thank Haobo for discussion).

Test Plan: Add new unit test. It throws SIGSEGV without this change. Also run "make all check".

Reviewers: haobo, dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13251
2013-10-02 17:33:31 -07:00
Xing Jin
8eb552bf4d New unit test for iterator with snapshot
Summary:
I played with the reported bug about iterator with snapshot:
https://code.google.com/p/leveldb/issues/detail?id=200.

I turned the original test program
(https://code.google.com/p/leveldb/issues/attachmentText?id=200&aid=2000000000&name=test.cc&token=7uOUQW-HFlbAFMUm7EqtaAEy7Tw%3A1378320724136)
into a new unit test, but I cannot reproduce the problem. Notice lines
31-34 in above link. I have ran the new test with and without such Put()
operations. Both succeed.

So this diff simply adds the test, without changing any source codes.

Test Plan: run new test.

Reviewers: dhruba, haobo, emayanke

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12735
2013-09-28 11:39:08 -07:00
Dhruba Borthakur
f1a60e5c3e The vector rep implementation was segfaulting because of incorrect initialization of vector.
Summary:
The constructor for Vector memtable has a parameter called 'count'
that specifies the capacity of the vector to be reserved at allocation
time. It was incorrectly used to initialize the size of the vector.

Test Plan: Enhanced db_test.

Reviewers: haobo, xjin, emayanke

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13083
2013-09-25 11:33:52 -07:00
Haobo Xu
72fcbf055d [RocksDB] Fix DBTest.UniversalCompactionSizeAmplification too
Summary: as title

Test Plan: make db_test; ./db_test

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13005
2013-09-17 21:29:33 -07:00
Haobo Xu
5b76338c01 [RocksDB] Fix DBTest.UniversalCompactionTrigger to reflect the correct compaction trigger condition.
Summary: as title

Test Plan: make db_test; ./db_test

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12981
2013-09-17 14:17:48 -07:00
Dhruba Borthakur
4012ca1c7b Added a parameter to limit the maximum space amplification for universal compaction.
Summary:
Added a new field called max_size_amplification_ratio in the
CompactionOptionsUniversal structure. This determines the maximum
percentage overhead of space amplification.

The size amplification is defined to be the ratio between the size of
the oldest file to the sum of the sizes of all other files. If the
size amplification exceeds the specified value, then min_merge_width
and max_merge_width are ignored and a full compaction of all files is done.
A value of 10 means that the size a database that stores 100 bytes
of user data could occupy 110 bytes of physical storage.

Test Plan: Unit test DBTest.UniversalCompactionSpaceAmplification added.

Reviewers: haobo, emayanke, xjin

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12825
2013-09-13 16:27:18 -07:00
Dhruba Borthakur
32c965d417 Flush was hanging because the configured options specified that more than 1 memtable need to be merged.
Summary:
There is an config option called Options.min_write_buffer_number_to_merge
that specifies the minimum number of write buffers to merge in memory
before flushing to a file in L0. But in the the case when the db is
being closed, we should not be using this config, instead we should
flush whatever write buffers were available at that time.

Test Plan: Unit test attached.

Reviewers: haobo, emayanke

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12717
2013-09-06 16:28:33 -07:00
Dhruba Borthakur
197034e4c3 An iterator may automatically invoke reseeks.
Summary:
An iterator invokes reseek if the number of sequential skips over the
same userkey exceeds a configured number. This makes iter->Next()
faster (bacause of fewer key compares) if a large number of
adjacent internal keys in a table (sst or memtable) have the
same userkey.

Test Plan: Unit test DBTest.IterReseek.

Reviewers: emayanke, haobo, xjin

Reviewed By: xjin

CC: leveldb, xjin

Differential Revision: https://reviews.facebook.net/D11865
2013-09-06 11:50:53 -07:00
Xing Jin
42c109cc2e New ldb command to convert compaction style
Summary:
Add new command "change_compaction_style" to ldb tool. For
universal->level, it shows "nothing to do". For level->universal, it
compacts all files into a single one and moves the file to level 0.

Also add check for number of files at level 1+ when opening db with
universal compaction style.

Test Plan:
'make all check'. New unit test for internal convertion function. Also manully test various
cmd like:

./ldb change_compaction_style --old_compaction_style=0
--new_compaction_style=1 --db=/tmp/leveldbtest-3088/db_test

Reviewers: haobo, dhruba

Reviewed By: haobo

CC: vamsi, emayanke

Differential Revision: https://reviews.facebook.net/D12603
2013-09-04 13:13:08 -07:00
Haobo Xu
48e5ea0c34 [RocksDB] Fix TransformRepFactory related valgrind problem
Summary: Let TransformRepFactory own the passed in transform. Also make it better encapsulated.

Test Plan: make valgrind_check;

Reviewers: dhruba, emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12591
2013-08-28 19:27:54 -07:00
Dhruba Borthakur
fc0c399d2e Introduced a new flag non_blocking_io in ReadOptions.
Summary:
If ReadOptions.non_blocking_io is set to true, then KeyMayExists
and Iterators will return data that is cached in RAM.
If the Iterator needs to do IO from storage to serve the data,
then the Iterator.status() will return Status::IsRetry().

Test Plan:
Enhanced unit test DBTest.KeyMayExist to detect if there were are IOs
issues from storage. Added DBTest.NonBlockingIteration to verify
nonblocking Iterations.

Reviewers: emayanke, haobo

Reviewed By: haobo

CC: leveldb

Maniphest Tasks: T63

Differential Revision: https://reviews.facebook.net/D12531
2013-08-28 10:49:14 -07:00
Mayank Agarwal
dad2731729 Fix bug in KeyMayExist
Summary: In KeyMayExist.db_test we do a Flush which causes sst file to be written and added as open file in TableCache, but block cache for the file is not populated. So value_found should have been false where it was true and KeyMayExist.db_test should not have passed earlier. But it passed because BlockReader in table/table.cc takes 2 default arguments at the end called for_compaction and no_io. Although I passed no_io=true from InternalGet to BlockReader, but it understood for_compaction=true and defaulted no_io to false. This is a bug and although will be removed by Dhruba's new patch to incorporate no_io in readoptions, I'm submitting this patch to fix this bug independently of that patch.

Test Plan: make all check

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12537
2013-08-26 08:45:58 -07:00
Dhruba Borthakur
1186192ed1 Replace include/leveldb with include/rocksdb.
Summary: Replace include/leveldb with include/rocksdb.

Test Plan:
make clean; make check
make clean; make release

Differential Revision: https://reviews.facebook.net/D12489
2013-08-23 10:51:00 -07:00
Jim Paton
74781a0c49 Add three new MemTableRep's
Summary:
This patch adds three new MemTableRep's: UnsortedRep, PrefixHashRep, and VectorRep.

UnsortedRep stores keys in an std::unordered_map of std::sets. When an iterator is requested, it dumps the keys into an std::set and iterates over that.

VectorRep stores keys in an std::vector. When an iterator is requested, it creates a copy of the vector and sorts it using std::sort. The iterator accesses that new vector.

PrefixHashRep stores keys in an unordered_map mapping prefixes to ordered sets.

I also added one API change. I added a function MemTableRep::MarkImmutable. This function is called when the rep is added to the immutable list. It doesn't do anything yet, but it seems like that could be useful. In particular, for the vectorrep, it means we could elide the extra copy and just sort in place. The only reason I haven't done that yet is because the use of the ArenaAllocator complicates things (I can elaborate on this if needed).

Test Plan:
make -j32 check
./db_stress --memtablerep=vector
./db_stress --memtablerep=unsorted
./db_stress --memtablerep=prefixhash --prefix_size=10

Reviewers: dhruba, haobo, emayanke

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12117
2013-08-22 23:10:02 -07:00
Deon Nicholas
b87dcae1a3 Made merge_oprator a shared_ptr; and added TTL unit tests
Test Plan:
- make all check;
- make release;
- make stringappend_test; ./stringappend_test

Reviewers: haobo, emayanke

Reviewed By: haobo

CC: leveldb, kailiu

Differential Revision: https://reviews.facebook.net/D12381
2013-08-20 13:35:28 -07:00
Mayank Agarwal
8a3547d38e API for getting archived log files
Summary: Also expanded class LogFile to have startSequene and FileSize and exposed it publicly

Test Plan: make all check

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12087
2013-08-19 13:37:04 -07:00
Jim Paton
0307c5fe3a Implement log blobs
Summary:
This patch adds the ability for the user to add sequences of arbitrary data (blobs) to write batches. These blobs are saved to the log along with everything else in the write batch. You can add multiple blobs per WriteBatch and the ordering of blobs, puts, merges, and deletes are preserved.

Blobs are not saves to SST files. RocksDB ignores blobs in every way except for writing them to the log.

Before committing this patch, I need to add some test code. But I'm submitting it now so people can comment on the API.

Test Plan: make -j32 check

Reviewers: dhruba, haobo, vamsi

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12195
2013-08-14 16:32:46 -07:00
Tyler Harter
f5f1842282 Prefix filters for scans (v4)
Summary: Similar to v2 (db and table code understands prefixes), but use ReadOptions as in v3.  Also, make the CreateFilter code faster and cleaner.

Test Plan: make db_test; export LEVELDB_TESTS=PrefixScan; ./db_test

Reviewers: dhruba

Reviewed By: dhruba

CC: haobo, emayanke

Differential Revision: https://reviews.facebook.net/D12027
2013-08-13 14:04:56 -07:00
sumeet
3b81df34bd Separate compaction filter for each compaction
Summary:
If we have same compaction filter for each compaction,
application cannot know about the different compaction processes.
Later on, we can put in more details in compaction filter for the
application to consume and use it according to its needs. For e.g. In
the universal compaction, we have a compaction process involving all the
files while others don't involve all the files. Applications may want to
collect some stats only when during full compaction.

Test Plan: run existing unit tests

Reviewers: haobo, dhruba

Reviewed By: dhruba

CC: xinyaohu, leveldb

Differential Revision: https://reviews.facebook.net/D12057
2013-08-13 10:56:20 -07:00
Dhruba Borthakur
93d77a27d2 Universal Compaction should keep DeleteMarkers unless it is the earliest file.
Summary:
The pre-existing code was purging a DeleteMarker if thay key did not
exist in deeper levels.  But in the Universal Compaction Style, all
files are in Level0. For compaction runs that did not include the
earliest file, we were erroneously purging the DeleteMarkers.

The fix is to purge DeleteMarkers only if the compaction includes
the earlist file.

Test Plan: DBTest.Randomized triggers this code path.

Differential Revision: https://reviews.facebook.net/D12081
2013-08-09 14:03:57 -07:00
Xing Jin
8ae905ed63 Fix unit tests for universal compaction (step 2)
Summary:
Continue fixing existing unit tests for universal compaction. I have
tried to apply universal compaction to all unit tests those haven't
called ChangeOptions(). I left a few which are either apparently not
applicable to universal compaction (because they check files/keys/values
at level 1 or above levels), or apparently not related to compaction
(e.g., open a file, open a db).

I also add a new unit test for universal compaction.

Good news is I didn't see any bugs during this round.

Test Plan: Ran "make all check" yesterday. Has rebased and is rerunning

Reviewers: haobo, dhruba

Differential Revision: https://reviews.facebook.net/D12135
2013-08-09 13:35:44 -07:00
Xing Jin
17b8f786a3 Fix unit tests/bugs for universal compaction (first step)
Summary:
This is the first step to fix unit tests and bugs for universal
compactiion. I added universal compaction option to ChangeOptions(), and
fixed all unit tests calling ChangeOptions(). Some of these tests
obviously assume more than 1 level and check file number/values in level
1 or above levels. I set kSkipUniversalCompaction for these tests.

The major bug I found is manual compaction with universal compaction never stops. I have put a fix for
it.

I have also set universal compaction as the default compaction and found
at least 20+ unit tests failing. I haven't looked into the details. The
next step is to check all unit tests without calling ChangeOptions().

Test Plan: make all check

Reviewers: dhruba, haobo

Differential Revision: https://reviews.facebook.net/D12051
2013-08-07 14:05:44 -07:00
Dhruba Borthakur
f5fa26b6a9 Merge branch 'performance' of github.com:facebook/rocksdb into performance
Conflicts:
	db/builder.cc
	db/db_impl.cc
	db/version_set.cc
	include/leveldb/statistics.h
2013-08-07 11:58:06 -07:00
Jim Paton
1036537c94 Add soft and hard rate limit support
Summary:
This diff adds support for both soft and hard rate limiting. The following changes are included:

1) Options.rate_limit is renamed to Options.hard_rate_limit.
2) Options.rate_limit_delay_milliseconds is renamed to Options.rate_limit_delay_max_milliseconds.
3) Options.soft_rate_limit is added.
4) If the maximum compaction score is > hard_rate_limit and rate_limit_delay_max_milliseconds == 0, then writes are delayed by 1 ms at a time until the max compaction score falls below hard_rate_limit.
5) If the max compaction score is > soft_rate_limit but <= hard_rate_limit, then writes are delayed by 0-1 ms depending on how close we are to hard_rate_limit.
6) Users can disable 4 by setting hard_rate_limit = 0. They can add a limit to the maximum amount of time waited by setting rate_limit_delay_max_milliseconds > 0. Thus, the old behavior can be preserved by setting soft_rate_limit = 0, which is the default.

Test Plan:
make -j32 check
./db_stress

Reviewers: dhruba, haobo, MarkCallaghan

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12003
2013-08-05 15:43:49 -07:00
Dhruba Borthakur
711a30cb30 Merge branch 'master' into performance
Conflicts:
	include/leveldb/options.h
	include/leveldb/statistics.h
	util/options.cc
2013-08-02 10:22:08 -07:00
Mayank Agarwal
59d0b02f8b Expand KeyMayExist to return the proper value if it can be found in memory and also check block_cache
Summary: Removed KeyMayExistImpl because KeyMayExist demanded Get like semantics now. Removed no_io from memtable and imm because we need the proper value now and shouldn't just stop when we see Merge in memtable. Added checks to block_cache. Updated documentation and unit-test

Test Plan: make all check;db_stress for 1 hour

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11853
2013-08-01 09:07:46 -07:00
Mayank Agarwal
bf66c10b13 Use KeyMayExist for WriteBatch-Deletes
Summary:
Introduced KeyMayExist checking during writebatch-delete and removed from Outer Delete API because it uses writebatch-delete.
Added code to skip getting Table from disk if not already present in table_cache.
Some renaming of variables.
Introduced KeyMayExistImpl which allows checking since specified sequence number in GetImpl useful to check partially written writebatch.
Changed KeyMayExist to not be pure virtual and provided a default implementation.
Expanded unit-tests in db_test to check appropriately.
Ran db_stress for 1 hour with ./db_stress --max_key=100000 --ops_per_thread=10000000 --delpercent=50 --filter_deletes=1 --statistics=1.

Test Plan: db_stress;make check

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb, xjin

Differential Revision: https://reviews.facebook.net/D11745
2013-07-23 13:36:50 -07:00
Haobo Xu
9ee68871dc [RocksDB] Enable manual compaction to move files back to an appropriate level.
Summary: As title. This diff added an option reduce_level to CompactRange. When set to true, it will try to move the files back to the minimum level sufficient to hold the data set. Note that the default is set to true now, just to excerise it in all existing tests. Will set the default to false before check-in, for backward compatibility.

Test Plan: make check;

Reviewers: dhruba, emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11553
2013-07-19 16:20:36 -07:00
Dhruba Borthakur
4a745a5666 Merge branch 'master' into performance
Conflicts:
	db/version_set.cc
	include/leveldb/options.h
	util/options.cc
2013-07-17 15:05:57 -07:00
Mayank Agarwal
e9b675bd94 Fix memory leak in KeyMayExist test part of db_test
Summary: NewBloomFilterPolicy call requires Delete to be called later on

Test Plan: make; valgrind ./db_test

Reviewers: haobo, dhruba, vamsi

Differential Revision: https://reviews.facebook.net/D11667
2013-07-12 16:58:57 -07:00
Mayank Agarwal
2a986919d6 Make rocksdb-deletes faster using bloom filter
Summary:
Wrote a new function in db_impl.c-CheckKeyMayExist that calls Get but with a new parameter turned on which makes Get return false only if bloom filters can guarantee that key is not in database. Delete calls this function and if the option- deletes_use_filter is turned on and CheckKeyMayExist returns false, the delete will be dropped saving:
1. Put of delete type
2. Space in the db,and
3. Compaction time

Test Plan:
make all check;
will run db_stress and db_bench and enhance unit-test once the basic design gets approved

Reviewers: dhruba, haobo, vamsi

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11607
2013-07-11 12:11:11 -07:00
Dhruba Borthakur
47c4191fe8 Reduce write amplification by merging files in L0 back into L0
Summary:
There is a new option called hybrid_mode which, when switched on,
causes HBase style compactions.  Files from L0 are
compacted back into L0. This meat of this compaction algorithm
is in PickCompactionHybrid().

All files reside in L0. That means all files have overlapping
keys. Each file has a time-bound, i.e. each file contains a
range of keys that were inserted around the same time. The
start-seqno and the end-seqno refers to the timeframe when
these keys were inserted.  Files that have contiguous seqno
are compacted together into a larger file. All files are
ordered from most recent to the oldest.

The current compaction algorithm starts to look for
candidate files starting from the most recent file. It continues to
add more files to the same compaction run as long as the
sum of the files chosen till now is smaller than the next
candidate file size. This logic needs to be debated
and validated.

The above logic should reduce write amplification to a
large extent... will publish numbers shortly.

Test Plan: dbstress runs for 6 hours with no data corruption (tested so far).

Differential Revision: https://reviews.facebook.net/D11289
2013-06-30 20:07:04 -07:00
Haobo Xu
bdf1085944 [RocksDB] cleanup EnvOptions
Summary:
This diff simplifies EnvOptions by treating it as POD, similar to Options.
- virtual functions are removed and member fields are accessed directly.
- StorageOptions is removed.
- Options.allow_readahead and Options.allow_readahead_compactions are deprecated.
- Unused global variables are removed: useOsBuffer, useFsReadAhead, useMmapRead, useMmapWrite

Test Plan: make check; db_stress

Reviewers: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11175
2013-06-12 11:17:19 -07:00
Deon Nicholas
db1f0cddf3 Fixed valgrind errors 2013-06-05 17:25:16 -07:00
Deon Nicholas
d8c7c45ea0 Very basic Multiget and simple test cases.
Summary:
Implemented the MultiGet operator which takes in a list of keys
and returns their associated values. Currently uses std::vector as its
container data structure. Otherwise, it works identically to "Get".

Test Plan:
 1. make db_test      ; compile it
 2. ./db_test         ; test it
 3. make all check    ; regress / run all tests
 4. make release      ; (optional) compile with release settings

Reviewers: haobo, MarkCallaghan, dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10875
2013-06-05 11:22:38 -07:00
Dhruba Borthakur
898f79372f Fix valgrind errors introduced by https://reviews.facebook.net/D10863
Summary:
The valgrind errors were in the unit tests where we change the
number of levels of a database using internal methods.

Test Plan:
valgrind ./reduce_levels_test
valgrind ./db_test

Reviewers: emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10893
2013-05-23 12:14:41 -07:00
Haobo Xu
4ca3c67bd3 [RocksDB] Cleanup compaction filter to use a class interface, instead of function pointer and additional context pointer.
Summary:
This diff replaces compaction_filter_args and CompactionFilter with a single compaction_filter parameter. It gives CompactionFilter better encapsulation and a similar look to Comparator and MergeOpertor, which improves consistency of the overall interface.
The change is not backward compatible. Nevertheless, the two references in fbcode are not in production yet.

Test Plan: make check

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb, zshao

Differential Revision: https://reviews.facebook.net/D10773
2013-05-13 14:06:10 -07:00
Haobo Xu
73c0a33346 [RocksDB] fix compaction filter trigger condition
Summary:
Currently, compaction filter is run on internal key older than the oldest snapshot, which is incorrect.
Compaction filter should really be run on the most recent internal key when there is no external snapshot.

Test Plan: make check; db_stress

Reviewers: dhruba

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D10641
2013-05-13 12:33:02 -07:00
Abhishek Kona
988c20b9f7 [RocksDB] Clear Archive WAL files
Summary:
WAL files are moved to archive directory and clear only at DB::Open.
Can lead to a lot of space consumption in a Database. Added logic to periodically clear Archive Directory too.

Test Plan: make all check + add unit test

Reviewers: dhruba, heyongqiang

Reviewed By: heyongqiang

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10617
2013-05-06 11:41:01 -07:00
Haobo Xu
05e8854085 [Rocksdb] Support Merge operation in rocksdb
Summary:
This diff introduces a new Merge operation into rocksdb.
The purpose of this review is mostly getting feedback from the team (everyone please) on the design.

Please focus on the four files under include/leveldb/, as they spell the client visible interface change.
include/leveldb/db.h
include/leveldb/merge_operator.h
include/leveldb/options.h
include/leveldb/write_batch.h

Please go over local/my_test.cc carefully, as it is a concerete use case.

Please also review the impelmentation files to see if the straw man implementation makes sense.

Note that, the diff does pass all make check and truly supports forward iterator over db and a version
of Get that's based on iterator.

Future work:
- Integration with compaction
- A raw Get implementation

I am working on a wiki that explains the design and implementation choices, but coding comes
just naturally and I think it might be a good idea to share the code earlier. The code is
heavily commented.

Test Plan: run all local tests

Reviewers: dhruba, heyongqiang

Reviewed By: dhruba

CC: leveldb, zshao, sheki, emayanke, MarkCallaghan

Differential Revision: https://reviews.facebook.net/D9651
2013-05-03 16:59:02 -07:00
Haobo Xu
eb6d139666 [RocksDB] Move table.h to table/
Summary:
- don't see a point exposing table.h to the public.
- fixed make clean to remove also *.d files.

Test Plan: make check; db_stress

Reviewers: dhruba, heyongqiang

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10479
2013-04-22 16:07:56 -07:00
Haobo Xu
b4243e5a3d [RocksDB] CompactionFilter cleanup
Summary:
- removed the compaction_filter_value from the callback interface. Restrict compaction filter to purging values.
- modify some comments to reflect curent status.

Test Plan: make check

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10335
2013-04-20 10:26:51 -07:00
Abhishek Kona
574b76f710 [RocksDB][Bug] Look at all the files, not just the first file in TransactionLogIter as BatchWrites can leave it in Limbo
Summary:
Transaction Log Iterator did not move to the next file in the series if there was a write batch at the end of the currentFile.
The solution is if the last seq no. of the current file is < RequestedSeqNo. Assume the first seqNo. of the next file has to satisfy the request.

Also major refactoring around the code. Moved opening the logreader to a seperate function, got rid of goto.

Test Plan: added a unit test for it.

Reviewers: dhruba, heyongqiang

Reviewed By: heyongqiang

CC: leveldb, emayanke

Differential Revision: https://reviews.facebook.net/D10029
2013-04-08 16:28:09 -07:00
Abhishek Kona
ca789a10cc [Rocksdb] Recover last updated sequence number from manifest also.
Summary:
During recovery, last_updated_manifest number was not set if there were no records in the Write-ahead log.
Now check for the recovered manifest also and set last_updated_manifest file to the max value.

Test Plan: unit test

Reviewers: heyongqiang

Reviewed By: heyongqiang

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9891
2013-04-02 17:18:27 -07:00
Abhishek Kona
8e9c781ae5 [Rocksdb] Fix Crash on finding a db with no log files. Error out instead
Summary:
If the vector returned by GetUpdatesSince is empty, it is still returned to the
user. This causes it throw an std::range error.
The probable file list is checked and it returns an IOError status instead of OK now.

Test Plan: added a unit test.

Reviewers: dhruba, heyongqiang

Reviewed By: heyongqiang

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9771
2013-03-28 13:19:07 -07:00
Abhishek Kona
7fdd5f5b33 Use non-mmapd files for Write-Ahead Files
Summary:
Use non mmapd files for Write-Ahead log.
Earlier use of MMaped files. made the log iterator read ahead and miss records.
Now the reader and writer will point to the same physical location.

There is no perf regression :
./db_bench --benchmarks=fillseq --db=/dev/shm/mmap_test --num=$(million 20) --use_existing_db=0 --threads=2
with This diff :
fillseq      :      10.756 micros/op 185281 ops/sec;   20.5 MB/s
without this dif :
fillseq      :      11.085 micros/op 179676 ops/sec;   19.9 MB/s

Test Plan: unit test included

Reviewers: dhruba, heyongqiang

Reviewed By: heyongqiang

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9741
2013-03-28 13:13:35 -07:00
Abhishek Kona
9b70529c86 Disable Unit Test for TransactionLogIteratorStall
Summary:
The unit test fails as our solution does not work with MMap'd files.
Disable the failing unit test. Put it back with the next diff which should fix the problem.

Test Plan: db_test

Reviewers: heyongqiang

CC: dhruba

Differential Revision: https://reviews.facebook.net/D9645
2013-03-21 15:51:18 -07:00
Abhishek Kona
27c15fb67e TransactionLogIter should stall at the last record. Currently it errors out
Summary:
* Add a method to check if the log reader is at EOF.
* If we know a record has been flushed force the log_reader to believe it is not at EOF, using a new method UnMarkEof().

This does not work with MMpaed files.

Test Plan: added a unit test.

Reviewers: dhruba, heyongqiang

Reviewed By: heyongqiang

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9567
2013-03-21 15:12:35 -07:00
Dhruba Borthakur
ad96563b79 Ability to configure bufferedio-reads, filesystem-readaheads and mmap-read-write per database.
Summary:
This patch allows an application to specify whether to use bufferedio,
reads-via-mmaps and writes-via-mmaps per database. Earlier, there
was a global static variable that was used to configure this functionality.

The default setting remains the same (and is backward compatible):
 1. use bufferedio
 2. do not use mmaps for reads
 3. use mmap for writes
 4. use readaheads for reads needed for compaction

I also added a parameter to db_bench to be able to explicitly specify
whether to do readaheads for compactions or not.

Test Plan: make check

Reviewers: sheki, heyongqiang, MarkCallaghan

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9429
2013-03-20 23:14:03 -07:00
Mayank Agarwal
b1bea58457 Fix more signed-unsigned comparisons
Summary: Some comparisons left in log_test.cc and db_test.cc complained by make

Test Plan: make

Reviewers: dhruba, sheki

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D9537
2013-03-19 17:21:36 -07:00
Abhishek Kona
02c459805b Ignore a zero-sized file while looking for a seq-no in GetUpdatesSince
Summary:
Rocksdb can create 0 sized log files when it is opened and closed without any operations.
The GetUpdatesSince fails currently if there is a log file of size zero.

This diff fixes this. If there is a log file is 0, it is removed form the probable_file_list

Test Plan: unit test

Reviewers: dhruba, heyongqiang

Reviewed By: heyongqiang

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9507
2013-03-19 11:00:09 -07:00
Abhishek Kona
d68880a1b9 Do not allow Transaction Log Iterator to fall ahead when writer is writing the same file
Summary:
Store the last flushed, seq no. in db_impl. Check against it in
transaction Log iterator. Do not attempt to read ahead if we do not know
if the data is flushed completely.
Does not work if flush is disabled. Any ideas on fixing that?
* Minor change, iter->Next is called the first time automatically for
* the first time.

Test Plan:
existing test pass.
More ideas on testing this?
Planning to run some stress test.

Reviewers: dhruba, heyongqiang

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9087
2013-03-06 14:05:53 -08:00
Mark Callaghan
993543d1be Add rate_delay_limit_milliseconds
Summary:
This adds the rate_delay_limit_milliseconds option to make the delay
configurable in MakeRoomForWrite when the max compaction score is too high.
This delay is called the Ln slowdown. This change also counts the Ln slowdown
per level to make it possible to see where the stalls occur.

From IO-bound performance testing, the Level N stalls occur:
* with compression -> at the largest uncompressed level. This makes sense
                      because compaction for compressed levels is much
                      slower. When Lx is uncompressed and Lx+1 is compressed
                      then files pile up at Lx because the (Lx,Lx+1)->Lx+1
                      compaction process is the first to be slowed by
                      compression.
* without compression -> at level 1

Task ID: #1832108

Blame Rev:

Test Plan:
run with real data, added test

Revert Plan:

Database Impact:

Memcache Impact:

Other Notes:

EImportant:

- begin *PUBLIC* platform impact section -
Bugzilla: #
- end platform impact -

Reviewers: dhruba

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D9045
2013-03-04 07:41:15 -08:00
Dhruba Borthakur
806e264350 Ability for rocksdb to compact when flushing the in-memory memtable to a file in L0.
Summary:
Rocks accumulates recent writes and deletes in the in-memory memtable.
When the memtable is full, it writes the contents on the memtable to
a file in L0.

This patch removes redundant records at the time of the flush. If there
are multiple versions of the same key in the memtable, then only the
most recent one is dumped into the output file. The purging of
redundant records occur only if the most recent snapshot is earlier
than the earliest record in the memtable.

Should we switch on this feature by default or should we keep this feature
turned off in the default settings?

Test Plan: Added test case to db_test.cc

Reviewers: sheki, vamsi, emayanke, heyongqiang

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D8991
2013-03-04 00:01:47 -08:00
Abhishek Kona
c41f1e995c Codemod NULL to nullptr
Summary:
scripted NULL to nullptr in
* include/leveldb/
* db/
* table/
* util/

Test Plan: make all check

Reviewers: dhruba, emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9003
2013-02-28 18:04:58 -08:00
Dhruba Borthakur
4564915446 Zero out redundant sequence numbers for kvs to increase compression efficiency
Summary:
The sequence numbers in each record eat up plenty of space on storage.
The optimization zeroes out sequence numbers on kvs in the Lmax
layer that are earlier than the earliest snapshot.

Test Plan: Unit test attached.

Differential Revision: https://reviews.facebook.net/D8619
2013-02-18 21:51:15 -08:00
Chip Turner
0b83a83191 Fix poor error on num_levels mismatch and few other minor improvements
Summary:
Previously, if you opened a db with num_levels set lower than
the database, you received the unhelpful message "Corruption:
VersionEdit: new-file entry."  Now you get a more verbose message
describing the issue.

Also, fix handling of compression_levels (both the run-over-the-end
issue and the memory management of it).

Lastly, unique_ptr'ify a couple of minor calls.

Test Plan: make check

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D8151
2013-01-25 15:37:26 -08:00
Chip Turner
3dafdfb2c4 Use fallocate to prevent excessive allocation of sst files and logs
Summary:
On some filesystems, pre-allocation can be a considerable
amount of space.  xfs in our production environment pre-allocates by
1GB, for instance.  By using fallocate to inform the kernel of our
expected file sizes, we eliminate this wasteage (that isn't recovered
until the file is closed which, in the case of LOG files, can be a
considerable amount of time).

Test Plan:
created an xfs loopback filesystem, mounted with
allocsize=4M, and ran db_stress.  LOG file without this change was 4M,
and with it it was 128k then grew to normal size.

Reviewers: dhruba

Reviewed By: dhruba

CC: adsharma, leveldb

Differential Revision: https://reviews.facebook.net/D7953
2013-01-24 12:25:13 -08:00
Chip Turner
2fdf91a4f8 Fix a number of object lifetime/ownership issues
Summary:
Replace manual memory management with std::unique_ptr in a
number of places; not exhaustive, but this fixes a few leaks with file
handles as well as clarifies semantics of the ownership of file handles
with log classes.

Test Plan: db_stress, make check

Reviewers: dhruba

Reviewed By: dhruba

CC: zshao, leveldb, heyongqiang

Differential Revision: https://reviews.facebook.net/D8043
2013-01-23 16:54:11 -08:00
Abhishek Kona
7d5a4383bb rollover manifest file.
Summary:
Check in LogAndApply if the file size is more than the limit set in
Options.
Things to consider : will this be expensive?

Test Plan: make all check. Inputs on a new unit test?

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D7701
2013-01-16 12:09:44 -08:00
Abhishek Kona
85ad13be1a Port fix for Leveldb manifest writing bug from Open-Source
Summary:
Pretty much a blind copy of the patch in open source.
Hope to get this in before we make a release

Test Plan: make clean check

Reviewers: dhruba, heyongqiang

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D7809
2013-01-10 12:06:03 -08:00
Kosie van der Merwe
62d48571de Added meta-database support.
Summary:
Added kMetaDatabase for meta-databases in db/filename.h along with supporting
fuctions.
Fixed switch in DBImpl so that it also handles kMetaDatabase.
Fixed DestroyDB() that it can handle destroying meta-databases.

Test Plan: make check

Reviewers: sheki, emayanke, vamsi, dhruba

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D7245
2012-12-17 11:26:59 -08:00
Abhishek Kona
2ba866e0c5 GetSequence API in write batch.
Summary:
WriteBatch is now used by the GetUpdatesSinceAPI. This API is external
and will be used by the rocks server. Rocks Server and others will need
to know about the Sequence Number in the WriteBatch. This public method
will allow for that.

Test Plan: make all check.

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D7293
2012-12-12 22:21:10 -08:00
Abhishek Kona
22c283625b Fix Bug in Binary Search for files containing a seq no. and delete Archived Log Files during Destroy DB.
Summary:
* Fixed implementation bug in Binary_Searvch introduced in https://reviews.facebook.net/D7119
* Binary search is also overflow safe.
* Delete archive log files and archive dir during DestroyDB

Test Plan: make check

Reviewers: dhruba

CC: kosievdmerwe, emayanke

Differential Revision: https://reviews.facebook.net/D7263
2012-12-11 16:15:02 -08:00
Dhruba Borthakur
24fc379273 An public api to fetch the latest transaction id.
Summary:
Implement a interface to retrieve the most current transaction
id from the database.

Test Plan: Added unit test.

Reviewers: sheki

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D7269
2012-12-10 16:04:19 -08:00
Abhishek Kona
1c6742e32f Refactor GetArchivalDirectoryName to filename.h
Summary:
filename.h has functions to do similar things.
Moving code away from db_impl.cc

Test Plan: make check

Reviewers: dhruba

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D7251
2012-12-10 10:51:07 -08:00
Abhishek Kona
8055008909 GetUpdatesSince API to enable replication.
Summary:
How it works:
* GetUpdatesSince takes a SequenceNumber.
* A LogFile with the first SequenceNumber nearest and lesser than the requested Sequence Number is found.
* Seek in the logFile till the requested SeqNumber is found.
* Return an iterator which contains logic to return record's one by one.

Test Plan:
* Test case included to check the good code path.
* Will update with more test-cases.
* Feedback required on test-cases.

Reviewers: dhruba, emayanke

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D7119
2012-12-07 11:42:13 -08:00
sheki
d4627e6de4 Move WAL files to archive directory, instead of deleting.
Summary:
Create a directory "archive" in the DB directory.
During DeleteObsolteFiles move the WAL files (*.log) to the Archive directory,
instead of deleting.

Test Plan: Created a DB using DB_Bench. Reopened it. Checked if files move.

Reviewers: dhruba

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D6975
2012-11-28 17:28:08 -08:00
Abhishek Kona
d29f181923 Fix all the lint errors.
Summary:
Scripted and removed all trailing spaces and converted all tabs to
spaces.

Also fixed other lint errors.
All lint errors from this point of time should be taken seriously.

Test Plan: make all check

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D7059
2012-11-28 17:18:41 -08:00
Dhruba Borthakur
9a357847eb Delete non-visible keys during a compaction even in the presense of snapshots.
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
2012-11-28 15:47:40 -08:00
Dhruba Borthakur
74054fa993 Fix compilation error while compiling unit tests with OPT=-g
Summary:
Fix compilation error while compiling with OPT=-g

Test Plan:
make clean check OPT=-g

Reviewers:

CC:

Task ID: #

Blame Rev:
2012-11-19 13:16:46 -08:00
amayank
de278a6de9 Fix a coding error in db_test.cc
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
2012-11-16 14:56:50 -08:00
Dhruba Borthakur
5d16e503a6 Improved CompactionFilter api: pass in a opaque argument to CompactionFilter invocation.
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
2012-11-13 16:22:26 -08:00
Abhishek Kona
4e413df3d0 Flush Data at object destruction if disableWal is used.
Summary:
Added a conditional flush in ~DBImpl to flush.
There is still a chance of writes not being persisted if there is a
crash (not a clean shutdown) before the DBImpl instance is destroyed.

Test Plan: modified db_test to meet the new expectations.

Reviewers: dhruba, heyongqiang

Differential Revision: https://reviews.facebook.net/D6519
2012-11-06 15:04:42 -08:00
Dhruba Borthakur
aa42c66814 Fix all warnings generated by -Wall option to the compiler.
Summary:
The default compilation process now uses "-Wall" to compile.
Fix all compilation error generated by gcc.

Test Plan: make all check

Reviewers: heyongqiang, emayanke, sheki

Reviewed By: heyongqiang

CC: MarkCallaghan

Differential Revision: https://reviews.facebook.net/D6525
2012-11-06 14:07:31 -08:00
Dhruba Borthakur
5273c81483 Ability to invoke application hook for every key during compaction.
Summary:
There are certain use-cases where the application intends to
delete older keys aftre they have expired a certian time period.
One option for those applications is to periodically scan the
entire database and delete appropriate keys.

A better way is to allow the application to hook into the
compaction process. This patch allows the application to set
a method callback for every key that is being compacted. If
this method returns true, then the key is not preserved in
the output of the compaction.

Test Plan:
This is mostly to preview the proposed new public api.
Since it is a public api, please do due diligence on reviewing it.

I will be writing test cases for this api in mynext version of
this patch.

Reviewers: MarkCallaghan, heyongqiang

Reviewed By: heyongqiang

CC: sheki, adsharma

Differential Revision: https://reviews.facebook.net/D6285
2012-11-05 16:02:13 -08:00
Dhruba Borthakur
a1bd5b7752 Compilation problem introduced by previous
commit 854c66b089.

Summary:
Compilation problem introduced by previous
commit 854c66b089.

Test Plan:  make check
2012-11-04 22:04:14 -08:00
amayank
854c66b089 Make compression options configurable. These include window-bits, level and strategy for ZlibCompression
Summary: Leveldb currently uses windowBits=-14 while using zlib compression.(It was earlier 15). This makes the setting configurable. Related changes here: https://reviews.facebook.net/D6105

Test Plan: make all check

Reviewers: dhruba, MarkCallaghan, sheki, heyongqiang

Differential Revision: https://reviews.facebook.net/D6393
2012-11-02 11:26:39 -07:00
heyongqiang
fb8d437325 fix test failure
Summary: as subject

Test Plan: db_test

Reviewers: dhruba, MarkCallaghan

Reviewed By: MarkCallaghan

Differential Revision: https://reviews.facebook.net/D6309
2012-10-29 18:55:52 -07:00
heyongqiang
925f60d39d add a test case to make sure chaning num_levels will fail Summary:
Summary: as subject

Test Plan: db_test

Reviewers: dhruba, MarkCallaghan

Reviewed By: MarkCallaghan

Differential Revision: https://reviews.facebook.net/D6303
2012-10-29 15:27:07 -07:00
Dhruba Borthakur
321dfdc3ae Allow having different compression algorithms on different levels.
Summary:
The leveldb API is enhanced to support different compression algorithms at
different levels.

This adds the option min_level_to_compress to db_bench that specifies
the minimum level for which compression should be done when
compression is enabled. This can be used to disable compression for levels
0 and 1 which are likely to suffer from stalls because of the CPU load
for memtable flushes and (L0,L1) compaction.  Level 0 is special as it
gets frequent memtable flushes. Level 1 is special as it frequently
gets all:all file compactions between it and level 0. But all other levels
could be the same. For any level N where N > 1, the rate of sequential
IO for that level should be the same. The last level is the
exception because it might not be full and because files from it are
not read to compact with the next larger level.

The same amount of time will be spent doing compaction at any
level N excluding N=0, 1 or the last level. By this standard all
of those levels should use the same compression. The difference is that
the loss (using more disk space) from a faster compression algorithm
is less significant for N=2 than for N=3. So we might be willing to
trade disk space for faster write rates with no compression
for L0 and L1, snappy for L2, zlib for L3. Using a faster compression
algorithm for the mid levels also allows us to reclaim some cpu
without trading off much loss in disk space overhead.

Also note that little is to be gained by compressing levels 0 and 1. For
a 4-level tree they account for 10% of the data. For a 5-level tree they
account for 1% of the data.

With compression enabled:
* memtable flush rate is ~18MB/second
* (L0,L1) compaction rate is ~30MB/second

With compression enabled but min_level_to_compress=2
* memtable flush rate is ~320MB/second
* (L0,L1) compaction rate is ~560MB/second

This practicaly takes the same code from https://reviews.facebook.net/D6225
but makes the leveldb api more general purpose with a few additional
lines of code.

Test Plan: make check

Differential Revision: https://reviews.facebook.net/D6261
2012-10-29 11:48:09 -07:00
Dhruba Borthakur
de7689b1d7 Fix unit test failure caused by delaying deleting obsolete files.
Summary:
A previous commit 4c107587ed introduced
the idea that some version updates might not delete obsolete files.
This means that if a unit test blindly counts the number of files
in the db directory it might not represent the true state of the database.

Use GetLiveFiles() insteads to count the number of live files in the database.

Test Plan:
make check
2012-10-29 11:12:24 -07:00
Dhruba Borthakur
c1bb32e1ba Trigger read compaction only if seeks to storage are incurred.
Summary:
In the current code, a Get() call can trigger compaction if it has to look at more than one file. This causes unnecessary compaction because looking at more than one file is a penalty only if the file is not yet in the cache. Also, th current code counts these files before the bloom filter check is applied.

This patch counts a 'seek' only if the file fails the bloom filter
check and has to read in data block(s) from the storage.

This patch also counts a 'seek' if a file is not present in the file-cache, because opening a file means that its index blocks need to be read into cache.

Test Plan: unit test attached. I will probably add one more unti tests.

Reviewers: heyongqiang

Reviewed By: heyongqiang

CC: MarkCallaghan

Differential Revision: https://reviews.facebook.net/D5709
2012-09-28 11:10:52 -07:00
Dhruba Borthakur
ae36e509f8 The BackupAPI should also list the length of the manifest file.
Summary:
The GetLiveFiles() api lists the set of sst files and the current
MANIFEST file. But the database continues to append new data to the
MANIFEST file even when the application is backing it up to the
backup location. This means that the database-version that is
stored in the MANIFEST FILE in the backup location
does not correspond to the sst files returned by GetLiveFiles.

This API adds a new parameter to GetLiveFiles. This new parmeter
returns the current size of the MANIFEST file.

Test Plan: Unit test attached.

Reviewers: heyongqiang

Reviewed By: heyongqiang

Differential Revision: https://reviews.facebook.net/D5631
2012-09-25 03:13:25 -07:00
Dhruba Borthakur
ba55d77b5d Ability to take a file-lvel snapshot from leveldb.
Summary:
A set of apis that allows an application to backup data from the
leveldb database based on a set of files.

Test Plan: unint test attached. more coming soon.

Reviewers: heyongqiang

Reviewed By: heyongqiang

Differential Revision: https://reviews.facebook.net/D5439
2012-09-17 09:14:50 -07:00
heyongqiang
0f43aa474e put log in a seperate dir
Summary: added a new option db_log_dir, which points the log dir. Inside that dir, in order to make log names unique, the log file name is prefixed with the leveldb data dir absolute path.

Test Plan: db_test

Reviewers: dhruba

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D5205
2012-09-06 17:52:08 -07:00
heyongqiang
a4f9b8b49e merge 1.5
Summary:

as subject

Test Plan:

db_test table_test

Reviewers: dhruba
2012-08-28 11:43:33 -07:00
heyongqiang
6fee5a74f5 Do not spin in a tight loop attempting compactions if there is a compaction error
Summary: as subject. ported the change from google code leveldb 1.5

Test Plan: run db_test

Reviewers: dhruba

Differential Revision: https://reviews.facebook.net/D4839
2012-08-28 11:43:33 -07:00
Dhruba Borthakur
e56b2c5a31 Prevent concurrent multiple opens of leveldb database.
Summary:
The fcntl call cannot detect lock conflicts when invoked multiple times
from the same thread.
Use a static lockedFile Set to record the paths that are locked.
A lockfile request checks to see if htis filename already exists in
lockedFiles, if so, then it triggers an error. Otherwise, it inserts
the filename in the lockedFiles Set.
A unlock file request verifies that the filename is in the lockedFiles
set and removes it from lockedFiles set.

Test Plan: unit test attached

Reviewers: heyongqiang

Reviewed By: heyongqiang

Differential Revision: https://reviews.facebook.net/D4755
2012-08-20 23:55:04 -07:00
heyongqiang
20ee76bd34 use ts as suffix for LOG.old files
Summary: as subject and only maintain 10 log files.

Test Plan: new test in db_test

Reviewers: dhruba

Differential Revision: https://reviews.facebook.net/D4731
2012-08-17 16:22:04 -07:00
heyongqiang
22ee777f68 add flush interface to DB
Summary: as subject. The flush will flush everything in the db.

Test Plan: new test in db_test.cc

Reviewers: dhruba

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D4029
2012-07-06 12:11:19 -07:00
heyongqiang
a347d4ac0d add disable WAL option
Summary: add disable WAL option

Test Plan: new testcase in db_test.cc

Reviewers: dhruba

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D4011
2012-07-05 15:06:56 -07:00
heyongqiang
4e4b6812ff Make some variables configurable for each db instance
Summary:
Make configurable 'targetFileSize', 'targetFileSizeMultiplier',
'maxBytesForLevelBase', 'maxBytesForLevelMultiplier',
'expandedCompactionFactor', 'maxGrandParentOverlapFactor'

Test Plan: N/A

Reviewers: dhruba

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D3801
2012-06-27 14:36:31 -07:00
Sanjay Ghemawat
85584d497e Added bloom filter support.
In particular, we add a new FilterPolicy class.  An instance
of this class can be supplied in Options when opening a
database.  If supplied, the instance is used to generate
summaries of keys (e.g., a bloom filter) which are placed in
sstables.  These summaries are consulted by DB::Get() so we
can avoid reading sstable blocks that are guaranteed to not
contain the key we are looking for.

This change provides one implementation of FilterPolicy
based on bloom filters.

Other changes:
- Updated version number to 1.4.
- Some build tweaks.
- C binding for CompactRange.
- A few more benchmarks: deleteseq, deleterandom, readmissing, seekrandom.
- Minor .gitignore update.
2012-04-17 08:36:46 -07:00
Sanjay Ghemawat
3c8be108bf fixed issues 66 (leaking files on disk error) and 68 (no sync of CURRENT file) 2012-01-25 14:56:52 -08:00
Hans Wennborg
42fb47f6ed Pass system's CFLAGS, remove exit time destructor, sstable bug fix.
- Pass system's values of CFLAGS,LDFLAGS.
  Don't override OPT if it's already set.
  Original patch by Alessio Treglia <alessio@debian.org>:
  http://code.google.com/p/leveldb/issues/detail?id=27#c6

- Remove 1 exit time destructor from leveldb.
  See http://crbug.com/101600

- Fix problem where sstable building code would pass an
  internal key to the user comparator.

(Sync with uptream at 25436817.)
2011-11-14 17:06:16 +00:00
Hans Wennborg
36a5f8ed7f A number of fixes:
- Replace raw slice comparison with a call to user comparator.
  Added test for custom comparators.

- Fix end of namespace comments.

- Fixed bug in picking inputs for a level-0 compaction.

  When finding overlapping files, the covered range may expand
  as files are added to the input set.  We now correctly expand
  the range when this happens instead of continuing to use the
  old range.  For example, suppose L0 contains files with the
  following ranges:

      F1: a .. d
      F2:    c .. g
      F3:       f .. j

  and the initial compaction target is F3.  We used to search
  for range f..j which yielded {F2,F3}.  However we now expand
  the range as soon as another file is added.  In this case,
  when F2 is added, we expand the range to c..j and restart the
  search.  That picks up file F1 as well.

  This change fixes a bug related to deleted keys showing up
  incorrectly after a compaction as described in Issue 44.

(Sync with upstream @25072954)
2011-10-31 17:22:06 +00:00
Gabor Cselle
299ccedfec A number of bugfixes:
- Added DB::CompactRange() method.

  Changed manual compaction code so it breaks up compactions of
  big ranges into smaller compactions.

  Changed the code that pushes the output of memtable compactions
  to higher levels to obey the grandparent constraint: i.e., we
  must never have a single file in level L that overlaps too
  much data in level L+1 (to avoid very expensive L-1 compactions).

  Added code to pretty-print internal keys.

- Fixed bug where we would not detect overlap with files in
  level-0 because we were incorrectly using binary search
  on an array of files with overlapping ranges.

  Added "leveldb.sstables" property that can be used to dump
  all of the sstables and ranges that make up the db state.

- Removing post_write_snapshot support.  Email to leveldb mailing
  list brought up no users, just confusion from one person about
  what it meant.

- Fixing static_cast char to unsigned on BIG_ENDIAN platforms.

  Fixes	Issue 35 and Issue 36.

- Comment clarification to address leveldb Issue 37.

- Change license in posix_logger.h to match other files.

- A build problem where uint32 was used instead of uint32_t.

Sync with upstream @24408625
2011-10-05 16:30:28 -07:00
gabor@google.com
7263023651 Bugfixes: for Get(), don't hold mutex while writing log.
- Fix bug in Get: when it triggers a compaction, it could sometimes
  mark the compaction with the wrong level (if there was a gap
  in the set of levels examined for the Get).

- Do not hold mutex while writing to the log file or to the
  MANIFEST file.

  Added a new benchmark that runs a writer thread concurrently with
  reader threads.

  Percentiles
  ------------------------------
  micros/op: avg  median 99   99.9  99.99  99.999 max
  ------------------------------------------------------
  before:    42   38     110  225   32000  42000  48000
  after:     24   20     55   65    130    1100   7000

- Fixed race in optimized Get.  It should have been using the
  pinned memtables, not the current memtables.



git-svn-id: https://leveldb.googlecode.com/svn/trunk@50 62dab493-f737-651d-591e-8d6aee1b9529
2011-09-01 19:08:02 +00:00
gabor@google.com
ab323f7e1e Bugfixes for iterator and documentation.
- Fix bug in Iterator::Prev where it would return the wrong key.
  Fixes issues 29 and 30.

- Added a tweak to testharness to allow running just some tests.

- Fixing two minor documentation errors based on issues 28 and 25.

- Cleanup; fix namespaces of export-to-C code.
  Also fix one "const char*" vs "char*" mismatch.



git-svn-id: https://leveldb.googlecode.com/svn/trunk@48 62dab493-f737-651d-591e-8d6aee1b9529
2011-08-16 01:21:01 +00:00
gabor@google.com
6872ace901 Sun Studio support, and fix for test related memory fixes.
- LevelDB patch for Sun Studio
  Based on a patch submitted by Theo Schlossnagle - thanks!
  This fixes Issue 17.

- Fix a couple of test related memory leaks.



git-svn-id: https://leveldb.googlecode.com/svn/trunk@38 62dab493-f737-651d-591e-8d6aee1b9529
2011-07-19 23:36:47 +00:00
gabor@google.com
6699c7ebe6 Small tweaks and bugfixes for Issue 18 and 19.
Slight tweak to the no-overlap optimization: only push to
level 2 to reduce the amount of wasted space when the same
small key range is being repeatedly overwritten.

Fix for Issue 18: Avoid failure on Windows by avoiding
deletion of lock file until the end of DestroyDB().

Fix for Issue 19: Disregard sequence numbers when checking for 
overlap in sstable ranges. This fixes issue 19: when writing 
the same key over and over again, we would generate a sequence 
of sstables that were never merged together since their sequence
numbers were disjoint.

Don't ignore map/unmap error checks.

Miscellaneous fixes for small problems Sanjay found while diagnosing
issue/9 and issue/16 (corruption_testr failures).
- log::Reader reports the record type when it finds an unexpected type.
- log::Reader no longer reports an error when it encounters an expected
  zero record regardless of the setting of the "checksum" flag.
- Added a missing forward declaration.
- Documented a side-effects of larger write buffer sizes
  (longer recovery time).



git-svn-id: https://leveldb.googlecode.com/svn/trunk@37 62dab493-f737-651d-591e-8d6aee1b9529
2011-07-15 00:20:57 +00:00
gabor@google.com
ccf0fcd5c2 A number of smaller fixes and performance improvements:
- Implemented Get() directly instead of building on top of a full
  merging iterator stack.  This speeds up the "readrandom" benchmark
  by up to 15-30%.

- Fixed an opensource compilation problem.
  Added --db=<name> flag to control where the database is placed.

- Automatically compact a file when we have done enough
  overlapping seeks to that file.

- Fixed a performance bug where we would read from at least one
  file in a level even if none of the files overlapped the key
  being read.

- Makefile fix for Mac OSX installations that have XCode 4 without XCode 3.

- Unified the two occurrences of binary search in a file-list
  into one routine.

- Found and fixed a bug where we would unnecessarily search the
  last file when looking for a key larger than all data in the
  level.

- A fix to avoid the need for trivial move compactions and
  therefore gets rid of two out of five syncs in "fillseq".

- Removed the MANIFEST file write when switching to a new
  memtable/log-file for a 10-20% improvement on fill speed on ext4.

- Adding a SNAPPY setting in the Makefile for folks who have
  Snappy installed. Snappy compresses values and speeds up writes.



git-svn-id: https://leveldb.googlecode.com/svn/trunk@32 62dab493-f737-651d-591e-8d6aee1b9529
2011-06-22 02:36:45 +00:00
dgrogan@chromium.org
740d8b3d00 Update from upstream @21551990
* Patch LevelDB to build for OSX and iOS
* Fix race condition in memtable iterator deletion.
* Other small fixes.

git-svn-id: https://leveldb.googlecode.com/svn/trunk@29 62dab493-f737-651d-591e-8d6aee1b9529
2011-05-28 00:53:58 +00:00
dgrogan@chromium.org
da79909507 sync with upstream @ 21409451
Check the NEWS file for details of what changed.

git-svn-id: https://leveldb.googlecode.com/svn/trunk@28 62dab493-f737-651d-591e-8d6aee1b9529
2011-05-21 02:17:43 +00:00
dgrogan@chromium.org
ba6dac0e80 @20776309
* env_chromium.cc should not export symbols.
* Fix MSVC warnings.
* Removed large value support.
* Fix broken reference to documentation file

git-svn-id: https://leveldb.googlecode.com/svn/trunk@24 62dab493-f737-651d-591e-8d6aee1b9529
2011-04-20 22:48:11 +00:00
dgrogan@chromium.org
69c6d38342 reverting disastrous MOE commit, returning to r21
git-svn-id: https://leveldb.googlecode.com/svn/trunk@23 62dab493-f737-651d-591e-8d6aee1b9529
2011-04-19 23:11:15 +00:00
dgrogan@chromium.org
b743906eea Revision created by MOE tool push_codebase.
MOE_MIGRATION=


git-svn-id: https://leveldb.googlecode.com/svn/trunk@22 62dab493-f737-651d-591e-8d6aee1b9529
2011-04-19 23:01:25 +00:00
dgrogan@chromium.org
b409afe968 chmod a-x
git-svn-id: https://leveldb.googlecode.com/svn/trunk@21 62dab493-f737-651d-591e-8d6aee1b9529
2011-04-18 23:15:58 +00:00
dgrogan@chromium.org
f779e7a5d8 @20602303. Default file permission is now 755.
git-svn-id: https://leveldb.googlecode.com/svn/trunk@20 62dab493-f737-651d-591e-8d6aee1b9529
2011-04-12 19:38:58 +00:00
jorlow@chromium.org
4671a695fc Move include files into a leveldb subdir.
git-svn-id: https://leveldb.googlecode.com/svn/trunk@18 62dab493-f737-651d-591e-8d6aee1b9529
2011-03-30 18:35:40 +00:00
jorlow@chromium.org
e11bdf1935 Upstream changes
git-svn-id: https://leveldb.googlecode.com/svn/trunk@15 62dab493-f737-651d-591e-8d6aee1b9529
2011-03-25 20:27:43 +00:00
jorlow@chromium.org
8303bb1b33 Pull from upstream.
git-svn-id: https://leveldb.googlecode.com/svn/trunk@14 62dab493-f737-651d-591e-8d6aee1b9529
2011-03-22 23:24:02 +00:00
jorlow@chromium.org
13b72af77b More changes from upstream.
git-svn-id: https://leveldb.googlecode.com/svn/trunk@12 62dab493-f737-651d-591e-8d6aee1b9529
2011-03-22 18:32:49 +00:00
jorlow@chromium.org
f67e15e50f Initial checkin.
git-svn-id: https://leveldb.googlecode.com/svn/trunk@2 62dab493-f737-651d-591e-8d6aee1b9529
2011-03-18 22:37:00 +00:00