[ 
https://issues.apache.org/jira/browse/HBASE-13291?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14390187#comment-14390187
 ] 

Anoop Sam John commented on HBASE-13291:
----------------------------------------

We can create a new Cell type extending KeyValue. This can include the cache 
for some of these lengths. In read path, when Cell is created from HFileScanner 
impls, we can create this new type. While adding Cells to Memstore we can make 
sure we have created old KeyValue objects only.  (So no overhead on heap size)

> Lift the scan ceiling
> ---------------------
>
>                 Key: HBASE-13291
>                 URL: https://issues.apache.org/jira/browse/HBASE-13291
>             Project: HBase
>          Issue Type: Improvement
>          Components: Scanners
>    Affects Versions: 1.0.0
>            Reporter: stack
>            Assignee: stack
>         Attachments: 13291.hacks.txt, 13291.inlining.txt, Screen Shot 
> 2015-03-26 at 12.12.13 PM.png, Screen Shot 2015-03-26 at 3.39.33 PM.png, 
> hack_to_bypass_bb.txt, nonBBposAndInineMvccVint.txt, q (1).png, traces.7.svg, 
> traces.filterall.svg, traces.nofilter.svg, traces.small2.svg, 
> traces.smaller.svg
>
>
> Scanning medium sized rows with multiple concurrent scanners exhibits 
> interesting 'ceiling' properties. A server runs at about 6.7k ops a second 
> using 450% of possible 1600% of CPUs  when 4 clients each with 10 threads 
> doing scan 1000 rows.  If I add '--filterAll' argument (do not return 
> results), then we run at 1450% of possible 1600% possible but we do 8k ops a 
> second.
> Let me attach flame graphs for two cases. Unfortunately, there is some 
> frustrating dark art going on. Let me try figure it... Filing issue in 
> meantime to keep score in.



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

Reply via email to