[jira] [Comment Edited] (PHOENIX-1278) Performance degradation for salted tables with guideposts

["James Taylor (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/PHOENIX-1278?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14144332#comment-14144332 ] 

James Taylor edited comment on PHOENIX-1278 at 9/23/14 4:57 AM:
----------------------------------------------------------------

+1. That seems fine for now, [~anoop.hbase]. I created PHOENIX-1279 for that.


was (Author: jamestaylor):
+1. That seems fine for now, [~anoop.hbase]. I'll create a new JIRA for that and we can leave this one open for now.

> Performance degradation for salted tables with guideposts
> ---------------------------------------------------------
>
>                 Key: PHOENIX-1278
>                 URL: https://issues.apache.org/jira/browse/PHOENIX-1278
>             Project: Phoenix
>          Issue Type: Bug
>            Reporter: James Taylor
>
> When a table is salted, we're seeing a degradation in performance using our new guidepost-based parallelization. With salted tables, we do a merge sort with the results from all the parallel scans. I suspect the cause here is that we're doing a merge sort now between more chunks than before (since we chunk everything up more now than we used to). We should group the scans we're doing for the same bucket together and do a concat with those results and then do a merge sort only with the concatenated batches.



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