hbase-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Lars Hofhansl (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HBASE-12411) Avoid seek + read completely?
Date Tue, 18 Nov 2014 04:20:35 GMT

    [ https://issues.apache.org/jira/browse/HBASE-12411?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14215690#comment-14215690
] 

Lars Hofhansl commented on HBASE-12411:
---------------------------------------

I could also enable p-read always with a default off switch, that way could get some easy
numbers there as well. Two more switches, though.

> Avoid seek + read completely?
> -----------------------------
>
>                 Key: HBASE-12411
>                 URL: https://issues.apache.org/jira/browse/HBASE-12411
>             Project: HBase
>          Issue Type: Brainstorming
>          Components: Performance
>            Reporter: Lars Hofhansl
>         Attachments: 12411-v2.txt, 12411.txt
>
>
> In the light of HDFS-6735 we might want to consider refraining from seek + read completely
and only perform preads.
> For example currently a compaction can lock out every other scanner over the file which
the compaction is currently reading for compaction.
> At the very least we can introduce an option to avoid seek + read, so we can allow testing
this in various scenarios.
> This will definitely be of great importance for projects like Phoenix which parallelize
queries intra region (and hence readers will used concurrently by multiple scanner with high
likelihood.)



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

Mime
View raw message