[jira] [Commented] (CASSANDRA-11853) Improve Cassandra-Stress latency measurement

["T Jake Luciani (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/CASSANDRA-11853?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15297097#comment-15297097 ] 

T Jake Luciani commented on CASSANDRA-11853:
--------------------------------------------

I've run some tests and non-throttled runs are unaffected (as expected)

With throttling on the following is seen

Trunk
{quote}
latency mean               : 1.1 ms [READ: 1.1 ms]
latency median             : 0.7 ms [READ: 0.7 ms]
latency 95th percentile    : 1.8 ms [READ: 1.8 ms]
latency 99th percentile    : 3.8 ms [READ: 3.8 ms]
latency 99.9th percentile  : 46.4 ms [READ: 46.4 ms]
latency max                : 163.8 ms [READ: 163.8 ms]
{quote}

Branch:
{quote}
latency mean               : 4.2 ms [READ: 4.2 ms]
latency median             : 0.7 ms [READ: 0.7 ms]
latency 95th percentile    : 29.0 ms [READ: 29.0 ms]
latency 99th percentile    : 57.7 ms [READ: 57.7 ms]
latency 99.9th percentile  : 211.8 ms [READ: 211.8 ms]
latency max                : 347.6 ms [READ: 347.6 ms]
{quote}

Which is a *HUGE* jump.  

> Improve Cassandra-Stress latency measurement
> --------------------------------------------
>
>                 Key: CASSANDRA-11853
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-11853
>             Project: Cassandra
>          Issue Type: Improvement
>          Components: Tools
>            Reporter: Nitsan Wakart
>            Assignee: Nitsan Wakart
>             Fix For: 3.x
>
>
> Currently CS reports latency using a sampling latency container and reporting service time (as opposed to response time from intended schedule) leading to coordinated omission.
> Fixed here:
> https://github.com/nitsanw/cassandra/tree/co-correction



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)