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
[Add a second kind of verification to db_stress

Summary:
Currently the test tracks all writes in memory and
uses it for verification at the end. This has 4 problems:
(a) It needs mutex for each write to ensure in-memory update
and leveldb update are done atomically. This slows down the
benchmark.
(b) Verification phase at the end is time consuming as well
(c) Does not test batch writes or snapshots
(d) We cannot kill the test and restart multiple times in a
loop because in-memory state will be lost.

I am adding a FLAGS_multi that does MultiGet/MultiPut/MultiDelete
instead of get/put/delete to get/put/delete a group of related
keys with same values atomically. Every get retrieves the group
of keys and checks that their values are same. This does not have
the above problems but the downside is that it does less amount
of validation than the other approach.

Test Plan:
This whole this is a test! Here is a small run. I am doing larger run now.

[nponnekanti@dev902 /data/users/nponnekanti/rocksdb] ./db_stress --ops_per_thread=10000 --multi=1 --ops_per_key=25
LevelDB version     : 1.5
Number of threads   : 32
Ops per thread      : 10000
Read percentage     : 10
Delete percentage   : 30
Max key             : 2147483648
Num times DB reopens: 10
Num keys per lock   : 4
Compression         : snappy
------------------------------------------------
Creating 536870912 locks
2013/02/20-16:59:32  Starting database operations
Created bg thread 0x7f9ebcfff700
2013/02/20-16:59:37  Reopening database for the 1th time
2013/02/20-16:59:46  Reopening database for the 2th time
2013/02/20-16:59:57  Reopening database for the 3th time
2013/02/20-17:00:11  Reopening database for the 4th time
2013/02/20-17:00:25  Reopening database for the 5th time
2013/02/20-17:00:36  Reopening database for the 6th time
2013/02/20-17:00:47  Reopening database for the 7th time
2013/02/20-17:00:59  Reopening database for the 8th time
2013/02/20-17:01:10  Reopening database for the 9th time
2013/02/20-17:01:20  Reopening database for the 10th time
2013/02/20-17:01:31  Reopening database for the 11th time
2013/02/20-17:01:31  Starting verification
Stress Test : 109.125 micros/op 22191 ops/sec
            : Wrote 0.00 MB (0.23 MB/sec) (59% of 32 ops)
            : Deleted 10 times
2013/02/20-17:01:31  Verification successful

Revert Plan: OK

Task ID: #

Reviewers: dhruba, emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D8733
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
Abilty to support upto a million .sst files in the database

Summary:
There was an artifical limit of 50K files per database. This is
insifficient if the database is 1 TB in size and each file is 2 MB.

Test Plan: make check

Reviewers: sheki, emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D8919
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
Automating valgrind to run with jenkins

Summary:
The script valgrind_test.sh runs Valgrind for all tests in the makefile
including leak-checks and outputs the logs for every test in a separate file
with the name "valgrind_log_<testname>". It prints the failed tests in the file
"valgrind_failed_tests". All these files are created in the directory
"VALGRIND_LOGS" which can be changed in the Makefile.
Finally it checks the line-count for the file "valgrind_failed_tests"
and returns 0 if no tests failed and 1 otherwise.

Test Plan: ./valgrind_test.sh; Changed the tests to incorporte leaks and verified correctness

Reviewers: dhruba, sheki, MarkCallaghan

Reviewed By: sheki

CC: zshao

Differential Revision: https://reviews.facebook.net/D8877
enable the ability to set key size in db_bench in rocksdb

Summary:
1. the default value for key size is still 16
2. enable the ability to set the key size via command line --key_size=

Test Plan:
build & run db_banch and pass some value via command line.
verify it works correctly.

Reviewers: sheki

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D8943
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
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
Removed unnecesary file object in table_cache.

Summary:
TableCache->file is not used. remove it.
I kept the TableAndFile structure and will clean it up in a future patch.

Test Plan: make clean check

Reviewers: sheki, chip

Reviewed By: chip

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9075
[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
Downgrade optimization level from -O3 to -O2.

Summary:
When we use -O3, the gcc 4.7.1 compiler generates 'pinsrd' which is
not supported on machines with "vendor_id       : AuthenticAMD".

Previous release of rocksdb used -O2.
Optimization -O2 was introduced at
https://github.com/facebook/rocksdb/commit/772f75b3fbc5cfcf4d519114751efeae04411fa1

Test Plan: make check

Reviewers: chip, heyongqiang, sheki

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9093
Fix Bash Script to run valgrind.

Test Plan: bash -n

Reviewers: emayanke

Differential Revision: https://reviews.facebook.net/D9129
add -j nproc in valgrind check script
Fox db_stress crash by copying keys before changing sequencenum to zero.

Summary:
The compaction process zeros out sequence numbers if the output is
part of the bottommost level.
The Slice is supposed to refer to an immutable data buffer. The
merger that implements the priority queue while reading kvs as
the input of a compaction run reies on this fact. The bug was that
were updating the sequence number of a record in-place and that was
causing suceeding invocations of the merger to return kvs in
arbitrary order of sequence numbers.
The fix is to copy the key to a local memory buffer before setting
its seqno to 0.

Test Plan:
Set Options.purge_redundant_kvs_while_flush = false and then run
db_stress --ops_per_thread=1000 --max_key=320

Reviewers: emayanke, sheki

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9147
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
Use version 3.8.1 for valgrind in third_party and do away with log files

Summary:
valgrind 3.7.0 used currently has a bug that needs LD_PRELOAD being set as a workaround. This caused problems when run on jenkins. 3.8.1 has fixed this issue and we should use it from third party
Also, have done away with log files. The whole output will be there on the terminal and the failed tests will be listed at the end. This is done because jenkins only lets us download the different files and not view them in the browser which is undesirable.

Test Plan: make valgrind_check

Reviewers: akushner, dhruba, vamsi, sheki, heyongqiang

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9171
A mechanism to detect manifest file write errors and put db in readonly mode.

Summary:
If there is an error while writing an edit to the manifest file, the manifest
file is closed and reopened to check if the edit made it in. However, if the
re-opening of the manifest is unsuccessful and options.paranoid_checks is set
t true, then the db refuses to accept new puts, effectively putting the db
in readonly mode.

In a future diff, I would like to make the default value of paranoid_check
to true.

Test Plan: make check

Reviewers: sheki

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9201
Make db_stress Not purge redundant keys on some opens

Summary: In light of the new option introduced by commit 806e26435037f5e2eb3b8c2d1e5f278a86fdb2ba where the database has an option to compact before flushing to disk, we want the stress test to test both sides of the option. Have made it to 'deterministically' and configurably change that option for reopens.

Test Plan: make db_stress; ./db_stress with some differnet options

Reviewers: dhruba, vamsi

Reviewed By: dhruba

CC: leveldb, sheki

Differential Revision: https://reviews.facebook.net/D9165
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