Find a file
Mark Callaghan e9e6b00d29 Add monitoring for universal compaction and add counters for compaction IO
Summary:
Adds these counters
{ WAL_FILE_SYNCED, "rocksdb.wal.synced" }
  number of writes that request a WAL sync
{ WAL_FILE_BYTES, "rocksdb.wal.bytes" },
  number of bytes written to the WAL
{ WRITE_DONE_BY_SELF, "rocksdb.write.self" },
  number of writes processed by the calling thread
{ WRITE_DONE_BY_OTHER, "rocksdb.write.other" },
  number of writes not processed by the calling thread. Instead these were
  processed by the current holder of the write lock
{ WRITE_WITH_WAL, "rocksdb.write.wal" },
  number of writes that request WAL logging
{ COMPACT_READ_BYTES, "rocksdb.compact.read.bytes" },
  number of bytes read during compaction
{ COMPACT_WRITE_BYTES, "rocksdb.compact.write.bytes" },
  number of bytes written during compaction

Per-interval stats output was updated with WAL stats and correct stats for universal compaction
including a correct value for write-amplification. It now looks like:
                               Compactions
Level  Files Size(MB) Score Time(sec)  Read(MB) Write(MB)    Rn(MB)  Rnp1(MB)  Wnew(MB) RW-Amplify Read(MB/s) Write(MB/s)      Rn     Rnp1     Wnp1     NewW    Count  Ln-stall Stall-cnt
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
  0        7      464  46.4       281      3411      3875      3411         0      3875        2.1      12.1        13.8      621        0      240      240      628       0.0         0
Uptime(secs): 310.8 total, 2.0 interval
Writes cumulative: 9999999 total, 9999999 batches, 1.0 per batch, 1.22 ingest GB
WAL cumulative: 9999999 WAL writes, 9999999 WAL syncs, 1.00 writes per sync, 1.22 GB written
Compaction IO cumulative (GB): 1.22 new, 3.33 read, 3.78 write, 7.12 read+write
Compaction IO cumulative (MB/sec): 4.0 new, 11.0 read, 12.5 write, 23.4 read+write
Amplification cumulative: 4.1 write, 6.8 compaction
Writes interval: 100000 total, 100000 batches, 1.0 per batch, 12.5 ingest MB
WAL interval: 100000 WAL writes, 100000 WAL syncs, 1.00 writes per sync, 0.01 MB written
Compaction IO interval (MB): 12.49 new, 14.98 read, 21.50 write, 36.48 read+write
Compaction IO interval (MB/sec): 6.4 new, 7.6 read, 11.0 write, 18.6 read+write
Amplification interval: 101.7 write, 102.9 compaction
Stalls(secs): 142.924 level0_slowdown, 0.000 level0_numfiles, 0.805 memtable_compaction, 0.000 leveln_slowdown
Stalls(count): 132461 level0_slowdown, 0 level0_numfiles, 3 memtable_compaction, 0 leveln_slowdown

Task ID: #3329644, #3301695

Blame Rev:

Test Plan:
Revert Plan:

Database Impact:

Memcache Impact:

Other Notes:

EImportant:

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

Reviewers: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14583
2013-12-12 13:27:43 -08:00
build_tools Add readrandom with both memtable and sst regression test 2013-12-11 13:51:20 -08:00
coverage
db Add monitoring for universal compaction and add counters for compaction IO 2013-12-12 13:27:43 -08:00
doc
hdfs
helpers/memenv
include Add monitoring for universal compaction and add counters for compaction IO 2013-12-12 13:27:43 -08:00
linters/src
port
table
tools
util [RocksDB perf] Cache speedup 2013-12-11 08:33:29 -08:00
utilities portable %lu printing 2013-12-12 08:13:47 -08:00
.arcconfig
.gitignore
CONTRIBUTING.md
INSTALL.md
LICENSE
Makefile
PATENTS
README
README.fb

rocksdb: A persistent key-value store for flash storage
Authors: * The Facebook Database Engineering Team
         * Build on earlier work on leveldb by Sanjay Ghemawat
           (sanjay@google.com) and Jeff Dean (jeff@google.com)

This code is a library that forms the core building block for a fast
key value server, especially suited for storing data on flash drives.
It has an Log-Structured-Merge-Database (LSM) design with flexible tradeoffs
between Write-Amplification-Factor(WAF), Read-Amplification-Factor (RAF)
and Space-Amplification-Factor(SAF). It has multi-threaded compactions,
making it specially suitable for storing multiple terabytes of data in a
single database.

The core of this code has been derived from open-source leveldb.

The code under this directory implements a system for maintaining a
persistent key/value store.

See doc/index.html and github wiki (https://github.com/facebook/rocksdb/wiki)
for more explanation.

The public interface is in include/*.  Callers should not include or
rely on the details of any other header files in this package.  Those
internal APIs may be changed without warning.

Guide to header files:

include/rocksdb/db.h
    Main interface to the DB: Start here

include/rocksdb/options.h
    Control over the behavior of an entire database, and also
    control over the behavior of individual reads and writes.

include/rocksdb/comparator.h
    Abstraction for user-specified comparison function.  If you want
    just bytewise comparison of keys, you can use the default comparator,
    but clients can write their own comparator implementations if they
    want custom ordering (e.g. to handle different character
    encodings, etc.)

include/rocksdb/iterator.h
    Interface for iterating over data. You can get an iterator
    from a DB object.

include/rocksdb/write_batch.h
    Interface for atomically applying multiple updates to a database.

include/rocksdb/slice.h
    A simple module for maintaining a pointer and a length into some
    other byte array.

include/rocksdb/status.h
    Status is returned from many of the public interfaces and is used
    to report success and various kinds of errors.

include/rocksdb/env.h
    Abstraction of the OS environment.  A posix implementation of
    this interface is in util/env_posix.cc

include/rocksdb/table_builder.h
    Lower-level modules that most clients probably won't use directly

include/rocksdb/cache.h
    An API for the block cache.

include/rocksdb/compaction_filter.h
    An API for a application filter invoked on every compaction.

include/rocksdb/filter_policy.h
    An API for configuring a bloom filter.

include/rocksdb/memtablerep.h
    An API for implementing a memtable.

include/rocksdb/statistics.h
    An API to retrieve various database statistics.

include/rocksdb/transaction_log.h
    An API to retrieve transaction logs from a database.