hbase-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "dhruba borthakur (JIRA)" <j...@apache.org>
Subject [jira] [Updated] (HBASE-3855) Performance degradation of memstore because reseek is linear
Date Fri, 06 May 2011 00:18:03 GMT

     [ https://issues.apache.org/jira/browse/HBASE-3855?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

dhruba borthakur updated HBASE-3855:
------------------------------------

    Status: Patch Available  (was: Open)

> Performance degradation of memstore because reseek is linear
> ------------------------------------------------------------
>
>                 Key: HBASE-3855
>                 URL: https://issues.apache.org/jira/browse/HBASE-3855
>             Project: HBase
>          Issue Type: Improvement
>            Reporter: dhruba borthakur
>            Assignee: dhruba borthakur
>            Priority: Blocker
>             Fix For: 0.94.0
>
>         Attachments: memstoreReseek.txt
>
>
> The scanner use reseek to find the next row (or next column) as part of a scan. The reseek
code iterates over a Set to position itself at the right place. If there are many thousands
of kvs that need to be skipped over, then the time-cost is very high. In this case, a seek
would be far lesser in cost than a reseek.

--
This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira

Mime
View raw message