[ 
https://issues.apache.org/jira/browse/HBASE-21738?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16746963#comment-16746963
 ] 

Zheng Hu commented on HBASE-21738:
----------------------------------

Tried to add a LongAdder (named cellSizeOfCSLM)  in CellSet,  but seems hard to 
maintain this member if the upper layer use iterator to remove an element, 
unless we rewrite the iterator...

> Remove all the CLSM#size operation in our memstore because it's an quite time 
> consuming.
> ----------------------------------------------------------------------------------------
>
>                 Key: HBASE-21738
>                 URL: https://issues.apache.org/jira/browse/HBASE-21738
>             Project: HBase
>          Issue Type: Sub-task
>          Components: Performance
>            Reporter: Zheng Hu
>            Assignee: Zheng Hu
>            Priority: Critical
>         Attachments: add-some-log.patch, image-2019-01-18-14-03-28-662.png, 
> log.txt
>
>
> Made some performance test for 100% put case in branch-2 before. 
> We can see that there are many  latency peak  in p999 latency curve , and the 
> peak time are almost the point time which our region is flushing. 
> See the [hbase20-ssd-put-10000000000-rows-latencys-and-qps 
> |https://issues.apache.org/jira/secure/attachment/12955341/12955341_image-2019-01-18-14-03-28-662.png]
> And, I used the 
> [add-some-log.patch|https://issues.apache.org/jira/secure/attachment/12955342/add-some-log.patch]
>  to log some time consuming when we grab the update.writeLock() to make a 
> memstore snapshot.   Tested again, I found those logs in [log.txt. 
> |https://issues.apache.org/jira/secure/attachment/12955343/log.txt]
> Seems most of the time was consumed when taking memstore snapshot.. Let me 
> dig into this.  



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

Reply via email to