Fluency
Yet another fluent logger
Mitsunori Komatsu
About me
• Mitsunori Komatsu, 

Software engineer
• github:komamitsu

msgpack-java

(jackson-dataformat-msgpack),

fluent-logger-java,

digdag,

:
Today’s talk
• What's Fluency?
• Internal design
• Performance and profiling
• Future improvements
Fluentd
What’s Fluency?
• Yet another fluent-logger-java

(https://github.com/komamitsu/fluency)
• 3x 4x faster than fluent-logger using
PackedForward format
• Easy to extend
• Many features

(Async flush, HB, Failover, Ack response)
• Used in LINE, Treasure Data, kafka-fluentd-consumer
Internal design
• Asynchronous flushing
• Buffering PackedForward format
data
Async flushing
Application Fluency Buffer FluentdFlusher
emit(event:A) append(event:A)
emit(event:B) append(event:B)
store events as
MessagePack
flush
send(event:[A, B])
emit(event:C) append(event:C)
flush
invoked
repeatedly
PackedForward
format
close close
force flush
emit(event:D) append(event:D)
send(event:[C,D])
event:C isn’t
ready for flush
event:A,B are
ready for flush
terminate
thread
Async flushing
Application Fluency Buffer FluentdFlusher
emit(event:A) append(event:A)
emit(event:B) append(event:B)
store events as
MessagePack
flush
send(event:[A, B])
emit(event:C) append(event:C)
flush
invoked
repeatedly
PackedForward
format
close close
force flush
emit(event:D) append(event:D)
send(event:[C,D])
event:C isn’t
ready for flush
event:A,B are
ready for flush
terminate
thread
Async flushing
Application Fluency Buffer FluentdFlusher
emit(event:A) append(event:A)
emit(event:B) append(event:B)
store events as
MessagePack
flush
send(event:[A, B])
emit(event:C) append(event:C)
flush
invoked
repeatedly
PackedForward
format
close close
force flush
emit(event:D) append(event:D)
send(event:[C,D])
event:C isn’t
ready for flush
event:A,B are
ready for flush
terminate
thread
Async flushing
Application Fluency Buffer FluentdFlusher
emit(event:A) append(event:A)
emit(event:B) append(event:B)
store events as
MessagePack
flush
send(event:[A, B])
emit(event:C) append(event:C)
flush
invoked
repeatedly
PackedForward
format
close close
force flush
emit(event:D) append(event:D)
send(event:[C,D])
event:C isn’t
ready for flush
event:A,B are
ready for flush
terminate
thread
Async flushing
Application Fluency Buffer FluentdFlusher
emit(event:A) append(event:A)
emit(event:B) append(event:B)
store events as
MessagePack
flush
send(event:[A, B])
emit(event:C) append(event:C)
flush
invoked
repeatedly
PackedForward
format
close close
force flush
emit(event:D) append(event:D)
send(event:[C,D])
event:C isn’t
ready for flush
event:A,B are
ready for flush
terminate
thread
Async flushing
Application Fluency Buffer FluentdFlusher
emit(event:A) append(event:A)
emit(event:B) append(event:B)
store events as
MessagePack
flush
send(event:[A, B])
emit(event:C) append(event:C)
flush
invoked
repeatedly
PackedForward
format
close close
force flush
emit(event:D) append(event:D)
send(event:[C,D])
event:C isn’t
ready for flush
event:A,B are
ready for flush
terminate
thread
Async flushing
Application Fluency Buffer FluentdFlusher
emit(event:A) append(event:A)
emit(event:B) append(event:B)
store events as
MessagePack
flush
send(event:[A, B])
emit(event:C) append(event:C)
flush
invoked
repeatedly
PackedForward
format
close close
force flush
emit(event:D) append(event:D)
send(event:[C,D])
event:C isn’t
ready for flush
event:A,B are
ready for flush
terminate
thread
Async flushing
Application Fluency Buffer FluentdFlusher
emit(event:A) append(event:A)
emit(event:B) append(event:B)
store events as
MessagePack
flush
send(event:[A, B])
emit(event:C) append(event:C)
flush
invoked
repeatedly
PackedForward
format
close close
force flush
emit(event:D) append(event:D)
send(event:[C,D])
event:C isn’t
ready for flush
event:A,B are
ready for flush
terminate
thread
Buffering events
tag: aaa,
time: 100,
{name: a_0}
Buffer
pool
retention buffers
flushable buffers
Fluentd
emit event
acquire buffer
Buffering events
tag: bbb,
time: 101,
{name: b_0}
Buffer
pool
time: 100, {name: a_0}
retention buffers
flushable buffers
tag: aaa
Fluentd
emit event
acquire buffer
Buffering events
tag: ccc,
time: 102,
{name: c_0}
Buffer
pool
time: 100, {name: a_0} time: 101, {name: b_0}
retention buffers
flushable buffers
tag: aaa tag: bbb
Fluentd
emit event
acquire buffer
Buffering events
tag: aaa,
time: 110,
{name: a_1}
Buffer
pool
time: 100, {name: a_0} time: 101, {name: b_0} time: 102, {name: c_0}
retention buffers
flushable buffers
tag: aaa tag: bbb tag: ccc
Fluentd
emit event
Buffering events
tag: aaa,
time: 120,
{name: a_2}
Buffer
pool
time: 100, {name: a_0}
time: 110, {name: a_1}
time: 101, {name: b_0} time: 102, {name: c_0}
retention buffers
flushable buffers
tag: aaa tag: bbb tag: ccc
Fluentd
emit event
expand buffer
Buffering events
tag: bbb,
time: 111,
{name: b_1}
:
:
Buffer
pool
time: 100, {name: a_0}
time: 110, {name: a_1}
time: 120, {name: a_2}
time: 101, {name: b_0} time: 102, {name: c_0}
retention buffers
flushable buffers
tag: aaa tag: bbb tag: ccc
Fluentd
emit event
Buffering events
tag: aaa,
time: 200,
{name: a_0}
Buffer
pool
time: 100, {name: a_0}
time: 110, {name: a_1}
time: 120, {name: a_2}
time: 130, {name: a_3}
time: 101, {name: b_0}
time: 111, {name: b_1}
time: 121, {name: b_2}
time: 131, {name: b_3}
time: 102, {name: c_0}
time: 112, {name: c_1}
retention buffers
flushable buffers
tag: aaa tag: bbb tag: ccc
Fluentd
emit event
move buffers
(zero copy)
tag: aaa
Buffering events
tag: ccc,
time: 122,
{name: c_2}
Buffer
pool
time: 200, {name: a_0} time: 102, {name: c_0}
time: 112, {name: c_1}
retention buffers
flushable buffers
tag: aaa tag: ccc
time: 100, {name: a_0}
time: 110, {name: a_1}
time: 120, {name: a_2}
time: 130, {name: a_3}
Fluentd
tag: bbb
time: 101, {name: b_0}
time: 111, {name: b_1}
time: 121, {name: b_2}
time: 131, {name: b_3}
emit event
expand buffer
send buffer
return buffer
(after sending)
PackedForword
format
Buffering events
tag: bbb,
time: 201,
{name: b_0}
Buffer
pool
time: 200, {name: a_0} time: 102, {name: c_0}
time: 112, {name: c_1}
retention buffers
flushable buffers
tag: aaa tag: ccc
Fluentd
tag: bbb
time: 101, {name: b_0}
time: 111, {name: b_1}
time: 121, {name: b_2}
time: 131, {name: b_3}
time: 122, {name: c_2}
emit event
send buffer
return buffer
(after sending)
acquire buffer
PackedForword
format
Buffering events
tag: aaa,
time: 210,
{name: a_1}
Buffer
pool
time: 200, {name: a_0} time: 102, {name: c_0}
time: 112, {name: c_1}
retention buffers
flushable buffers
tag: aaa tag: ccc
Fluentd
time: 122, {name: c_2}
time: 201, {name: b_0}
tag: bbb
emit event
4x faster than

fluent-logger-java
fluency / fluent-logger-java: m3.large
fluentd: m3.large
See details: https://gist.github.com/komamitsu/c1e4045fe2ddb108cfbf12d5f014b683
But the actual
bottleneck
of this benchmark
might be Fluentd…
Java profiling (1/2)
fluency fluent-logger-java
fluency uses off heap
for buffer pool
Due to synchronization
Java profiling (2/2)
fluency fluent-logger-java
GC Pause: 33ms/s GC Pause: 7ms/s
Finding a bottleneck
fluency
emit (MessagePack
serialization & appending to
buffer) accounts for most of
the duration
String.getBytes in
MessagePack serialization
takes total 18%
ObjectMapper.writeValue
itself takes 40%
Finding a bottleneck
fluency
MessagePackGenerator.
writeStartArray takes 10%
java.nio.channels.SocketCh
annel.write and
java.nio.ByteBuffer.allocate
Direct are both 0-1%
Finding a bottleneck
fluent-logger-java
Sending events via socket
accounts for most of the
duration
Future improvements:
removing ObjectMapper
ObjectMapper
can be removed
to improve
performance?
Hmm. But Fluency
accepts Jackson
Modules…
Future improvements:
reducing use of ObjectMapper
ObjectMapper is needed only for
serialisation of data not array
Thanks!

Fluency - Yet another fluent logger

  • 1.
    Fluency Yet another fluentlogger Mitsunori Komatsu
  • 2.
    About me • MitsunoriKomatsu, 
 Software engineer • github:komamitsu
 msgpack-java
 (jackson-dataformat-msgpack),
 fluent-logger-java,
 digdag,
 :
  • 3.
    Today’s talk • What'sFluency? • Internal design • Performance and profiling • Future improvements
  • 4.
  • 5.
    What’s Fluency? • Yetanother fluent-logger-java
 (https://github.com/komamitsu/fluency) • 3x 4x faster than fluent-logger using PackedForward format • Easy to extend • Many features
 (Async flush, HB, Failover, Ack response) • Used in LINE, Treasure Data, kafka-fluentd-consumer
  • 6.
    Internal design • Asynchronousflushing • Buffering PackedForward format data
  • 7.
    Async flushing Application FluencyBuffer FluentdFlusher emit(event:A) append(event:A) emit(event:B) append(event:B) store events as MessagePack flush send(event:[A, B]) emit(event:C) append(event:C) flush invoked repeatedly PackedForward format close close force flush emit(event:D) append(event:D) send(event:[C,D]) event:C isn’t ready for flush event:A,B are ready for flush terminate thread
  • 8.
    Async flushing Application FluencyBuffer FluentdFlusher emit(event:A) append(event:A) emit(event:B) append(event:B) store events as MessagePack flush send(event:[A, B]) emit(event:C) append(event:C) flush invoked repeatedly PackedForward format close close force flush emit(event:D) append(event:D) send(event:[C,D]) event:C isn’t ready for flush event:A,B are ready for flush terminate thread
  • 9.
    Async flushing Application FluencyBuffer FluentdFlusher emit(event:A) append(event:A) emit(event:B) append(event:B) store events as MessagePack flush send(event:[A, B]) emit(event:C) append(event:C) flush invoked repeatedly PackedForward format close close force flush emit(event:D) append(event:D) send(event:[C,D]) event:C isn’t ready for flush event:A,B are ready for flush terminate thread
  • 10.
    Async flushing Application FluencyBuffer FluentdFlusher emit(event:A) append(event:A) emit(event:B) append(event:B) store events as MessagePack flush send(event:[A, B]) emit(event:C) append(event:C) flush invoked repeatedly PackedForward format close close force flush emit(event:D) append(event:D) send(event:[C,D]) event:C isn’t ready for flush event:A,B are ready for flush terminate thread
  • 11.
    Async flushing Application FluencyBuffer FluentdFlusher emit(event:A) append(event:A) emit(event:B) append(event:B) store events as MessagePack flush send(event:[A, B]) emit(event:C) append(event:C) flush invoked repeatedly PackedForward format close close force flush emit(event:D) append(event:D) send(event:[C,D]) event:C isn’t ready for flush event:A,B are ready for flush terminate thread
  • 12.
    Async flushing Application FluencyBuffer FluentdFlusher emit(event:A) append(event:A) emit(event:B) append(event:B) store events as MessagePack flush send(event:[A, B]) emit(event:C) append(event:C) flush invoked repeatedly PackedForward format close close force flush emit(event:D) append(event:D) send(event:[C,D]) event:C isn’t ready for flush event:A,B are ready for flush terminate thread
  • 13.
    Async flushing Application FluencyBuffer FluentdFlusher emit(event:A) append(event:A) emit(event:B) append(event:B) store events as MessagePack flush send(event:[A, B]) emit(event:C) append(event:C) flush invoked repeatedly PackedForward format close close force flush emit(event:D) append(event:D) send(event:[C,D]) event:C isn’t ready for flush event:A,B are ready for flush terminate thread
  • 14.
    Async flushing Application FluencyBuffer FluentdFlusher emit(event:A) append(event:A) emit(event:B) append(event:B) store events as MessagePack flush send(event:[A, B]) emit(event:C) append(event:C) flush invoked repeatedly PackedForward format close close force flush emit(event:D) append(event:D) send(event:[C,D]) event:C isn’t ready for flush event:A,B are ready for flush terminate thread
  • 15.
    Buffering events tag: aaa, time:100, {name: a_0} Buffer pool retention buffers flushable buffers Fluentd emit event acquire buffer
  • 16.
    Buffering events tag: bbb, time:101, {name: b_0} Buffer pool time: 100, {name: a_0} retention buffers flushable buffers tag: aaa Fluentd emit event acquire buffer
  • 17.
    Buffering events tag: ccc, time:102, {name: c_0} Buffer pool time: 100, {name: a_0} time: 101, {name: b_0} retention buffers flushable buffers tag: aaa tag: bbb Fluentd emit event acquire buffer
  • 18.
    Buffering events tag: aaa, time:110, {name: a_1} Buffer pool time: 100, {name: a_0} time: 101, {name: b_0} time: 102, {name: c_0} retention buffers flushable buffers tag: aaa tag: bbb tag: ccc Fluentd emit event
  • 19.
    Buffering events tag: aaa, time:120, {name: a_2} Buffer pool time: 100, {name: a_0} time: 110, {name: a_1} time: 101, {name: b_0} time: 102, {name: c_0} retention buffers flushable buffers tag: aaa tag: bbb tag: ccc Fluentd emit event expand buffer
  • 20.
    Buffering events tag: bbb, time:111, {name: b_1} : : Buffer pool time: 100, {name: a_0} time: 110, {name: a_1} time: 120, {name: a_2} time: 101, {name: b_0} time: 102, {name: c_0} retention buffers flushable buffers tag: aaa tag: bbb tag: ccc Fluentd emit event
  • 21.
    Buffering events tag: aaa, time:200, {name: a_0} Buffer pool time: 100, {name: a_0} time: 110, {name: a_1} time: 120, {name: a_2} time: 130, {name: a_3} time: 101, {name: b_0} time: 111, {name: b_1} time: 121, {name: b_2} time: 131, {name: b_3} time: 102, {name: c_0} time: 112, {name: c_1} retention buffers flushable buffers tag: aaa tag: bbb tag: ccc Fluentd emit event move buffers (zero copy)
  • 22.
    tag: aaa Buffering events tag:ccc, time: 122, {name: c_2} Buffer pool time: 200, {name: a_0} time: 102, {name: c_0} time: 112, {name: c_1} retention buffers flushable buffers tag: aaa tag: ccc time: 100, {name: a_0} time: 110, {name: a_1} time: 120, {name: a_2} time: 130, {name: a_3} Fluentd tag: bbb time: 101, {name: b_0} time: 111, {name: b_1} time: 121, {name: b_2} time: 131, {name: b_3} emit event expand buffer send buffer return buffer (after sending) PackedForword format
  • 23.
    Buffering events tag: bbb, time:201, {name: b_0} Buffer pool time: 200, {name: a_0} time: 102, {name: c_0} time: 112, {name: c_1} retention buffers flushable buffers tag: aaa tag: ccc Fluentd tag: bbb time: 101, {name: b_0} time: 111, {name: b_1} time: 121, {name: b_2} time: 131, {name: b_3} time: 122, {name: c_2} emit event send buffer return buffer (after sending) acquire buffer PackedForword format
  • 24.
    Buffering events tag: aaa, time:210, {name: a_1} Buffer pool time: 200, {name: a_0} time: 102, {name: c_0} time: 112, {name: c_1} retention buffers flushable buffers tag: aaa tag: ccc Fluentd time: 122, {name: c_2} time: 201, {name: b_0} tag: bbb emit event
  • 25.
    4x faster than
 fluent-logger-java fluency/ fluent-logger-java: m3.large fluentd: m3.large See details: https://gist.github.com/komamitsu/c1e4045fe2ddb108cfbf12d5f014b683 But the actual bottleneck of this benchmark might be Fluentd…
  • 26.
    Java profiling (1/2) fluencyfluent-logger-java fluency uses off heap for buffer pool Due to synchronization
  • 27.
    Java profiling (2/2) fluencyfluent-logger-java GC Pause: 33ms/s GC Pause: 7ms/s
  • 28.
    Finding a bottleneck fluency emit(MessagePack serialization & appending to buffer) accounts for most of the duration String.getBytes in MessagePack serialization takes total 18% ObjectMapper.writeValue itself takes 40%
  • 29.
    Finding a bottleneck fluency MessagePackGenerator. writeStartArraytakes 10% java.nio.channels.SocketCh annel.write and java.nio.ByteBuffer.allocate Direct are both 0-1%
  • 30.
    Finding a bottleneck fluent-logger-java Sendingevents via socket accounts for most of the duration
  • 31.
    Future improvements: removing ObjectMapper ObjectMapper canbe removed to improve performance? Hmm. But Fluency accepts Jackson Modules…
  • 32.
    Future improvements: reducing useof ObjectMapper ObjectMapper is needed only for serialisation of data not array
  • 33.