cassandra-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "David Allsopp (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (CASSANDRA-2850) Converting bytes to hex string is unnecessarily slow
Date Sun, 03 Jul 2011 19:45:21 GMT

    [ https://issues.apache.org/jira/browse/CASSANDRA-2850?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13059268#comment-13059268
] 

David Allsopp commented on CASSANDRA-2850:
------------------------------------------

Updated diff (2850a) includes the same optimisation in both the FBUtilities version and the
ByteBufferUtils version, with similar x3 speedup in each case. Now uses a literal lookup table
rather than generating it in static block.

> Converting bytes to hex string is unnecessarily slow
> ----------------------------------------------------
>
>                 Key: CASSANDRA-2850
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-2850
>             Project: Cassandra
>          Issue Type: Improvement
>          Components: Core
>    Affects Versions: 0.7.6, 0.8.1
>            Reporter: David Allsopp
>            Priority: Minor
>             Fix For: 0.8.2
>
>         Attachments: BytesToHexBenchmark.java, BytesToHexBenchmark2.java, cassandra-2850a.diff
>
>
> ByteBufferUtil.bytesToHex() is unnecessarily slow - it doesn't pre-size the StringBuilder
(so several re-sizes will be needed behind the scenes) and it makes quite a few method calls
per byte.
> (OK, this may be a premature optimisation, but I couldn't resist, and it's a small change)
> Will attach patch shortly that speeds it up by about x3, plus benchmarking test.

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

        

Mime
View raw message