[
https://issues.apache.org/jira/browse/HBASE-7247?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13510452#comment-13510452
]
nkeywal commented on HBASE-7247:
--------------------------------
The patch is getting thinner and thinner...
Now I just check that the znode was not updated recently before writing it
again. On the test, it brings half of was I have it I remove totally
tickleOpening.
There is something there as well, in OpenRegionHandler#process()
{code}
boolean failed = true;
if (tickleOpening("post_region_open")) {
if (updateMeta(region)) {
failed = false;
}
}
if (failed || this.server.isStopped() ||
{code}
This 'tickleOpening' is called whatever the time spent previously, before
updating meta. If we remove it completely, we save a sync.
> Assignment performances decreased by 50% because of
> regionserver.OpenRegionHandler#tickleOpening
> ------------------------------------------------------------------------------------------------
>
> Key: HBASE-7247
> URL: https://issues.apache.org/jira/browse/HBASE-7247
> Project: HBase
> Issue Type: Improvement
> Components: master, Region Assignment, regionserver
> Affects Versions: 0.96.0
> Reporter: nkeywal
> Assignee: nkeywal
> Priority: Critical
> Fix For: 0.96.0
>
> Attachments: 7247.v1.patch
>
>
> The regionserver.OpenRegionHandler#tickleOpening updates the region znode as
> "Do this so master doesn't timeout this region-in-transition.".
> However, on the usual test, this makes the assignment time of 1500 regions
> goes from 70s to 100s, that is, we're 50% slower because of this.
> More generally, ZooKeper commits to disk all the data update, and this takes
> time. Using it to provide a keep alive seems overkill. At the very list, it
> could be made asynchronous.
> I'm not sure how necessary these updates are required (I need to go deeper in
> the internal, feedback welcome), but it seems very important to optimize
> this... The trival fix would be to make this optional.
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira
