[jira] [Commented] (CASSANDRA-8341) Expose time spent in each thread pool

["Chris Lohfink (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/CASSANDRA-8341?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14218111#comment-14218111 ] 

Chris Lohfink commented on CASSANDRA-8341:
------------------------------------------

Attached a first pass patch for an idea.  I just recorded the wall time but may want to record cpu time as well ([getCurrentThreadCpuTime & getCurrentThreadUserTime|https://docs.oracle.com/javase/7/docs/api/java/lang/management/ThreadMXBean.html#getCurrentThreadCpuTime()]).  May be worth recording it with a histogram instead of just a counter as well, but for the purpose of exposing % of time I think the total is sufficient.  I added an insertion meter as well for easier time in estimating different pool sizes (just easier then adding up the pending/completed/active and give sense of rate).

> Expose time spent in each thread pool
> -------------------------------------
>
>                 Key: CASSANDRA-8341
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-8341
>             Project: Cassandra
>          Issue Type: New Feature
>          Components: Core
>            Reporter: Chris Lohfink
>            Priority: Minor
>              Labels: metrics
>         Attachments: 8341.patch
>
>
> Can increment a counter with time spent in each queue.  This can provide context on how much time is spent percentage wise in each stage.  Additionally can be used with littles law in future if ever want to try to tune the size of the pools.



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