[
https://issues.apache.org/jira/browse/KAFKA-3565?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15252123#comment-15252123
]
Jiangjie Qin commented on KAFKA-3565:
-------------------------------------
[~jkreps] The google doc should be accessible now.
I think the change in uncompressed case is expected because of the 8-bytes
additional cost. The MB/s reported in ProducerPerformance seems based on the
actual message size which does not include the message header overhead.
I benchmarked the compression of bounded random integers in the producer with
jmh:
{code}
Benchmark (bufferSize) (recordSize) (valueBound)
Mode Cnt Score Error Units
ClientMicroBenchMark.compression 1024 100 500
avgt 20 152745.539 ± 198435.342 ns/op
ClientMicroBenchMark.compression 1024 100 5000
avgt 20 106698.904 ± 111624.120 ns/op
ClientMicroBenchMark.compression 1024 100 50000
avgt 20 104670.802 ± 110694.704 ns/op
ClientMicroBenchMark.compression 1024 1000 500
avgt 20 169223.272 ± 180063.271 ns/op
ClientMicroBenchMark.compression 1024 1000 5000
avgt 20 118949.514 ± 122875.686 ns/op
ClientMicroBenchMark.compression 1024 1000 50000
avgt 20 130193.581 ± 140485.913 ns/op
{code}
I benchmarked System.currentTimeMillis() some time ago as well, it took single
digit nano seconds. So It seems ignorable compared with compression time.
>From [~ijuma] test, it seems the gap is around 8-10% in the throughput of user
>bytes when message size is 100. Is this different from what we saw before
>which has 17% gap? What was the integer range of the test? And how many
>records were sent during the test? One thing I noticed is that it takes a few
>seconds for the throughput to become stable, so if the tests finished very
>quickly, the results may not be quite accurate. The tests I ran adjusted the
>records number dynamically to let the testing time be at least 15 seconds.
> Producer's throughput lower with compressed data after KIP-31/32
> ----------------------------------------------------------------
>
> Key: KAFKA-3565
> URL: https://issues.apache.org/jira/browse/KAFKA-3565
> Project: Kafka
> Issue Type: Bug
> Reporter: Ismael Juma
> Priority: Critical
> Fix For: 0.10.0.0
>
>
> Relative offsets were introduced by KIP-31 so that the broker does not have
> to recompress data (this was previously required after offsets were
> assigned). The implicit assumption is that reducing CPU usage required by
> recompression would mean that producer throughput for compressed data would
> increase.
> However, this doesn't seem to be the case:
> {code}
> Commit: eee95228fabe1643baa016a2d49fb0a9fe2c66bd (one before KIP-31/32)
> test_id:
> 2016-04-15--012.kafkatest.tests.benchmark_test.Benchmark.test_producer_throughput.topic=topic-replication-factor-three.security_protocol=PLAINTEXT.acks=1.message_size=100.compression_type=snappy
> status: PASS
> run time: 59.030 seconds
> {"records_per_sec": 519418.343653, "mb_per_sec": 49.54}
> {code}
> Full results: https://gist.github.com/ijuma/0afada4ff51ad6a5ac2125714d748292
> {code}
> Commit: fa594c811e4e329b6e7b897bce910c6772c46c0f (KIP-31/32)
> test_id:
> 2016-04-15--013.kafkatest.tests.benchmark_test.Benchmark.test_producer_throughput.topic=topic-replication-factor-three.security_protocol=PLAINTEXT.acks=1.message_size=100.compression_type=snappy
> status: PASS
> run time: 1 minute 0.243 seconds
> {"records_per_sec": 427308.818848, "mb_per_sec": 40.75}
> {code}
> Full results: https://gist.github.com/ijuma/e49430f0548c4de5691ad47696f5c87d
> The difference for the uncompressed case is smaller (and within what one
> would expect given the additional size overhead caused by the timestamp
> field):
> {code}
> Commit: eee95228fabe1643baa016a2d49fb0a9fe2c66bd (one before KIP-31/32)
> test_id:
> 2016-04-15--010.kafkatest.tests.benchmark_test.Benchmark.test_producer_throughput.topic=topic-replication-factor-three.security_protocol=PLAINTEXT.acks=1.message_size=100
> status: PASS
> run time: 1 minute 4.176 seconds
> {"records_per_sec": 321018.17747, "mb_per_sec": 30.61}
> {code}
> Full results: https://gist.github.com/ijuma/5fec369d686751a2d84debae8f324d4f
> {code}
> Commit: fa594c811e4e329b6e7b897bce910c6772c46c0f (KIP-31/32)
> test_id:
> 2016-04-15--014.kafkatest.tests.benchmark_test.Benchmark.test_producer_throughput.topic=topic-replication-factor-three.security_protocol=PLAINTEXT.acks=1.message_size=100
> status: PASS
> run time: 1 minute 5.079 seconds
> {"records_per_sec": 291777.608696, "mb_per_sec": 27.83}
> {code}
> Full results: https://gist.github.com/ijuma/1d35bd831ff9931448b0294bd9b787ed
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
