Commit Graph

109 Commits

Author SHA1 Message Date
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
Mayank Agarwal
3102628873 Bring read_only into ttl
Summary: added an argument to openttldb for read only and open the db in normal readonly mode if the arguments is set to true

Test Plan: make ttl_test; ./ttl_test

Reviewers: dhruba, haobo, vamsi, sheki

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10749
2013-05-10 16:13:26 -07:00
Abhishek Kona
8d58ecdc29 [RocksDB] Expose compaction stalls via db_statistics
Test Plan: make check

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10575
2013-05-10 14:41:45 -07:00
Abhishek Kona
d98e56315d [RocksDB] Make Ticker Atomic
Summary:
Our ticker was not atomic. This was based on the assumption that we will increment counts at places only protected by Mutex. This is hard to program for and easy to make mistakes (mutex may be held a few layers above etc).
Also this increases the instructions executed when the mutex is held.

Test Plan: make check

Reviewers: haobo, dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10569
2013-05-10 13:19:39 -07:00
Mayank Agarwal
ff1a0801fc Correct path of db.h in utility_db.h
Summary: Will not be caught properly from file in fbcode with old path. New path fixes it.

Test Plan: make

Reviewers: sheki, dhruba, haobo, vamsi

Reviewed By: sheki

Differential Revision: https://reviews.facebook.net/D10707
2013-05-09 17:32:39 -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
Mayank Agarwal
d786b25e2d Timestamp and TTL Wrapper for rocksdb
Summary:
When opened with DBTimestamp::Open call, timestamps are prepended to and stripped from the value during subsequent Put and Get calls respectively. The Timestamp is used to discard values in Get and custom compaction filter which have exceeded their TTL which is specified during Open.
Have made a temporary change to Makefile to let us test with the temporary file TestTime.cc. Have also changed the private members of db_impl.h to protected to let them be inherited by the new class DBTimestamp

Test Plan: make db_timestamp; TestTime.cc(will not check it in) shows how to use the apis currently, but I will write unit-tests shortly

Reviewers: dhruba, vamsi, haobo, sheki, heyongqiang, vkrest

Reviewed By: vamsi

CC: zshao, xjin, vkrest, MarkCallaghan

Differential Revision: https://reviews.facebook.net/D10311
2013-05-02 16:34:42 -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
dae7379050 [RocksDB] Expose LDB functioanality as a library call - clients can build their own LDB binary with additional options
Summary: Primarily a refactor. Introduced LDBTool interface to which customers can plug in their options and this will create their own version of ldb tool.

Test Plan: made ldb tool and tried it.

Reviewers: dhruba, heyongqiang

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10191
2013-04-11 20:21:49 -07:00
heyongqiang
e21ba94a69 Set FD_CLOEXEC after each file open
Summary: as subject. This is causing problem in adsconv. Ideally, this flags should be set in open. But that is only supported in Linux kernel ≥2.6.23 and glibc ≥2.7.

Test Plan:
db_test

run db_test

Reviewers: dhruba, MarkCallaghan, haobo

Reviewed By: dhruba

CC: leveldb, chip

Differential Revision: https://reviews.facebook.net/D10089
2013-04-10 14:44:06 -07:00
Abhishek Kona
63f216ee0a memory manage statistics
Summary:
Earlier Statistics object was a raw pointer. This meant the user had to clear up
the Statistics object after creating the database. In most use cases the database is created in a function and the statistics pointer is out of scope. Hence the statistics object would never be deleted.
Now Using a shared_ptr to manage this.

Want this in before the next release.

Test Plan: make all check.

Reviewers: dhruba, emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9735
2013-03-27 11:27:39 -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
487168cdcf Fixed sign-comparison in rocksdb code-base and fixed Makefile
Summary: Makefile had options to ignore sign-comparisons and unused-parameters, which should be there. Also fixed the specific errors in the code-base

Test Plan: make

Reviewers: chip, dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9531
2013-03-19 14:35:23 -07:00
Dhruba Borthakur
469724be7f Add appropriate parameters to make bulk-load go faster.
Summary:
1. Create only 2 levels so that manual compactions are fast.
2. Set target file size to a large value

Test Plan: make clean check

Reviewers: kailiu, zshao

Reviewed By: zshao

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9231
2013-03-08 10:52:16 -08:00
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
Zheng Shao
7b43500794 [RocksDB] Add bulk_load option to Options and ldb
Summary:
Add a shortcut function to make it easier for people
to efficiently bulk_load data into RocksDB.

Test Plan:
Tried ldb with "--bulk_load" and "--bulk_load --compact" and verified the outcome.
Needs to consult the team on how to test this automatically.

Reviewers: sheki, dhruba, emayanke, heyongqiang

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D8907
2013-03-05 00:34:53 -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
Abhishek Kona
a9866b721b Refactor statistics. Remove individual functions like incNumFileOpens
Summary:
Use only the counter mechanism. Do away with
incNumFileOpens, incNumFileClose, incNumFileErrors
s/NULL/nullptr/g in db/table_cache.cc

Test Plan: make clean check

Reviewers: dhruba, heyongqiang, emayanke

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D8841
2013-02-25 13:58:34 -08:00
Abhishek Kona
959337ed5b Measure compaction time.
Summary: just record time consumed in compaction

Test Plan: compile

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D8781
2013-02-22 11:38:40 -08:00
Abhishek Kona
ec77366e14 Counters for bytes written and read.
Summary:
* Counters for bytes read and write.
as a part of this diff, I want to=>
* Measure compaction times. @dhruba can you point which function, should
* I time to get Compaction-times. Was looking at CompactRange.

Test Plan: db_test

Reviewers: dhruba, emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D8763
2013-02-21 16:06:32 -08:00
Abhishek Kona
fe10200ddc Introduce histogram in statistics.h
Summary:
* Introduce is histogram in statistics.h
* stop watch to measure time.
* introduce two timers as a poc.
Replaced NULL with nullptr to fight some lint errors
Should be useful for google.

Test Plan:
ran db_bench and check stats.
make all check

Reviewers: dhruba, heyongqiang

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D8637
2013-02-20 10:43:32 -08:00
Kai Liu
b63aafce42 Allow the logs to be purged by TTL.
Summary:
* Add a SplitByTTLLogger to enable this feature. In this diff I implemented generalized AutoSplitLoggerBase class to simplify the
development of such classes.
* Refactor the existing AutoSplitLogger and fix several bugs.

Test Plan:
* Added a unit tests for different types of "auto splitable" loggers individually.
* Tested the composited logger which allows the log files to be splitted by both TTL and log size.

Reviewers: heyongqiang, dhruba

Reviewed By: heyongqiang

CC: zshao, leveldb

Differential Revision: https://reviews.facebook.net/D8037
2013-02-04 19:42:40 -08:00
Kosie van der Merwe
4dcc0c89f4 Fixed cache key for block cache
Summary:
Added function to `RandomAccessFile` to generate an unique ID for that file. Currently only `PosixRandomAccessFile` has this behaviour implemented and only on Linux.

Changed how key is generated in `Table::BlockReader`.

Added tests to check whether the unique ID is stable, unique and not a prefix of another unique ID. Added tests to see that `Table` uses the cache more efficiently.

Test Plan: make check

Reviewers: chip, vamsi, dhruba

Reviewed By: chip

CC: leveldb

Differential Revision: https://reviews.facebook.net/D8145
2013-01-31 15:20:24 -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
16903c35b0 Add counters to count gets and writes
Summary: Add Tickers to count Write's and Get's

Test Plan: make check

Reviewers: dhruba, chip

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D7977
2013-01-17 12:27:56 -08:00
amayank
4b1e9f0a35 Added an API in rocksdb for checking for "invalid argument" and "not supported" for leveldb::Status
Summary: a function added to status.h to check whether Status::code is InvalidArgument and similarly for NotSupported state

Test Plan: visual inspection

Reviewers: heyongqiang, dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D7989
2013-01-16 14:30:45 -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
Chip Turner
c0cb289d57 Various build cleanups/improvements
Summary:
Specific changes:

1) Turn on -Werror so all warnings are errors
2) Fix some warnings the above now complains about
3) Add proper dependency support so changing a .h file forces a .c file
to rebuild
4) Automatically use fbcode gcc on any internal machine rather than
whatever system compiler is laying around
5) Fix jemalloc to once again be used in the builds (seemed like it
wasn't being?)
6) Fix issue where 'git' would fail in build_detect_version because of
LD_LIBRARY_PATH being set in the third-party build system

Test Plan:
make, make check, make clean, touch a header file, make sure
rebuild is expected

Reviewers: dhruba

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D7887
2013-01-14 18:40:22 -08:00
Dhruba Borthakur
f4c2b7cf97 Enhance ReadOnly mode to process the all committed transactions.
Summary:
Leveldb has an api OpenForReadOnly() that opens the database
in readonly mode. This call had an option to not process the
transaction log.  This patch removes this option and always
processes all transactions that had been committed. It has
been done in such a way that it does not create/write to
any new files in the process. The invariant of "no-writes"
to the leveldb data directory is still true.

This enhancement allows multiple threads to open the same database
in readonly mode and access all trancations that were committed right
upto the OpenForReadOnly call.

I changed the public API to match the new semantics because
there are no users who are currently using this api.

Test Plan: make clean check

Reviewers: sheki

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D7479
2012-12-19 16:30:46 -08:00
Dhruba Borthakur
3d1e92b05a Enhancements to rocksdb for better support for replication.
Summary:
1. The OpenForReadOnly() call should not lock the db. This is useful
so that multiple processes can open the same database concurrently
for reading.
2. GetUpdatesSince should not error out if the archive directory
does not exist.
3. A new constructor for WriteBatch that can takes a serialized
string as a parameter of the constructor.

Test Plan: make clean check

Reviewers: sheki

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D7449
2012-12-17 11:40:19 -08:00
Zheng Shao
c28097538a manifest_dump: Add --hex=1 option
Summary: Without this option, manifest_dump does not print binary keys for files in a human-readable way.

Test Plan:
./manifest_dump --hex=1 --verbose=0 --file=/data/users/zshao/fdb_comparison/leveldb/fbobj.apprequest-0_0_original/MANIFEST-000002
manifest_file_number 589 next_file_number 590 last_sequence 2311567 log_number 543  prev_log_number 0
--- level 0 --- version# 0 ---
 532:1300357['0000455BABE20000' @ 2183973 : 1 .. 'FFFCA5D7ADE20000' @ 2184254 : 1]
 536:1308170['000198C75CE30000' @ 2203313 : 1 .. 'FFFCF94A79E30000' @ 2206463 : 1]
 542:1321644['0002931AA5E50000' @ 2267055 : 1 .. 'FFF77B31C5E50000' @ 2270754 : 1]
 544:1286390['000410A309E60000' @ 2278592 : 1 .. 'FFFE470A73E60000' @ 2289221 : 1]
 538:1298778['0006BCF4D8E30000' @ 2217050 : 1 .. 'FFFD77DAF7E30000' @ 2220489 : 1]
 540:1282353['00090D5356E40000' @ 2231156 : 1 .. 'FFFFF4625CE40000' @ 2231969 : 1]
--- level 1 --- version# 0 ---
 510:2112325['000007F9C2D40000' @ 1782099 : 1 .. '146F5B67B8D80000' @ 1905458 : 1]
 511:2121742['146F8A3023D60000' @ 1824388 : 1 .. '28BC8FBB9CD40000' @ 1777993 : 1]
 512:801631['28BCD396F1DE0000' @ 2080191 : 1 .. '3082DBE9ADDB0000' @ 1989927 : 1]

Reviewers: dhruba, sheki, emayanke

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D7425
2012-12-16 08:58:28 -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
Dhruba Borthakur
d0a30935c6 Expose the serialized string that represents a WriteBatch.
Summary:
Expose the serialized string that represents a WriteBatch. This
is helpful to replicate a writebatch operation from one machine
to another.

Test Plan: make clean check

Reviewers: sheki

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D7317
2012-12-12 16:25:52 -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
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
7632fdb5cb Support taking a configurable number of files from the same level to compact in a single compaction run.
Summary:
The compaction process takes some files from LevelK and
merges it into LevelK+1. The number of files it picks from
LevelK was capped such a way that the total amount of
data picked does not exceed the maxfilesize of that level.
This essentially meant that only one file from LevelK
is picked for a single compaction.

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

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

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

Test Plan: make clean check

Reviewers: emayanke, sheki

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D6867
2012-11-21 08:37:03 -08:00
Dhruba Borthakur
fbb73a4ac3 Support to disable background compactions on a database.
Summary:
This option is needed for fast bulk uploads. The goal is to load
all the data into files in L0 without any interference from
background compactions.

Test Plan: make clean check

Reviewers: sheki

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D6849
2012-11-20 21:12:06 -08:00
Dhruba Borthakur
6c5a4d646a Merge branch 'master' into performance
Conflicts:
	db/db_impl.h
2012-11-14 21:39:52 -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
0f8e4721a5 Metrics: record compaction drop's and bloom filter effectiveness
Summary: Record BloomFliter hits and drop off reasons during compaction.

Test Plan: Unit tests work.

Reviewers: dhruba, heyongqiang

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D6591
2012-11-09 11:38:45 -08:00
heyongqiang
20d18a89a3 disable size compaction in ldb reduce_levels and added compression and file size parameter to it
Summary:
disable size compaction in ldb reduce_levels, this will avoid compactions rather than the manual comapction,

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

Test Plan: run ldb

Reviewers: dhruba, MarkCallaghan

Reviewed By: dhruba

CC: sheki, emayanke

Differential Revision: https://reviews.facebook.net/D6597
2012-11-09 10:14:47 -08:00
Abhishek Kona
391885c4e4 stat's collection in leveldb
Summary:
Prototype stat's collection. Diff is a good estimate of what
the final code will look like.
A few assumptions :
  * Used a global static instance of the statistics object. Plan to pass
  it to each internal function. Static allows metrics only at app
  level.
  * In the Ticker's do not do any locking. Depend on the mutex at each
   function of LevelDB. If we ever remove the mutex, we should change
   here too. The other option is use atomic objects anyways as there
   won't be any contention as they will be always acquired only by one
   thread.
  * The counters are dumb, increment through lifecycle. Plan to use ods
    etc to get last5min stat etc.

Test Plan:
made changes in db_bench
Ran ./db_bench --statistics=1 --num=10000 --cache_size=5000
This will print the cache hit/miss stats.

Reviewers: dhruba, heyongqiang

Differential Revision: https://reviews.facebook.net/D6441
2012-11-08 13:55:49 -08:00
heyongqiang
3fcf533ed0 Add a readonly db
Summary: as subject

Test Plan: run db_bench readrandom

Reviewers: dhruba

Reviewed By: dhruba

CC: MarkCallaghan, emayanke, sheki

Differential Revision: https://reviews.facebook.net/D6495
2012-11-07 14:19:48 -08:00