[
https://issues.apache.org/jira/browse/HBASE-3308?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14661571#comment-14661571
]
chenxu commented on HBASE-3308:
-------------------------------
when i read the patch, i find this line
int nbFiles = hstoreFilesToSplit.size();
the hstoreFilesToSplit is a Map, not a List, if you want get all the
StoreFiles, the code may be not right.
> SplitTransaction.splitStoreFiles slows splits a lot
> ---------------------------------------------------
>
> Key: HBASE-3308
> URL: https://issues.apache.org/jira/browse/HBASE-3308
> Project: HBase
> Issue Type: Improvement
> Reporter: Jean-Daniel Cryans
> Assignee: Jean-Daniel Cryans
> Priority: Critical
> Fix For: 0.90.0, 0.92.0
>
> Attachments: HBASE-3308-0.89.patch, HBASE-3308.patch
>
>
> Recently I've been seeing some slow splits in our production environment
> triggering timeouts, so I decided to take a closer look into the issue.
> According to my debugging, we spend almost all the time it takes to split on
> creating the reference files. Each file in my testing takes at least 300ms to
> create, and averages around 600ms. Since we create two references per store
> file, it means that a region with 4 store file can easily take up to 5
> seconds to split just to create those references.
> An intuitive improvement would be to create those files in parallel, so at
> least it wouldn't be much slower when we're splitting a higher number of
> files. Stack left the following comment in the code:
> {noformat}
> // TODO: If the below were multithreaded would we complete steps in less
> // elapsed time? St.Ack 20100920
> {noformat}
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
