cassandra-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Stu Hood (JIRA)" <j...@apache.org>
Subject [jira] Commented: (CASSANDRA-1891) large supercolumn deserialization invokes CSLM worst case scenario
Date Thu, 23 Dec 2010 08:57:01 GMT

    [ https://issues.apache.org/jira/browse/CASSANDRA-1891?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12974571#action_12974571
] 

Stu Hood commented on CASSANDRA-1891:
-------------------------------------

This applies cleanly to trunk, but fails a lot of the supercolumn related tests. Also, what
kind of performance benefits do you see? It would appear that CSLM does not override putAll
from AbstractMap, so putAll is probably equivalent to individual sorted calls to put. Finally,
if this is a win, might it be possible to override the interesting methods on an existing
SortedMap impl (like TreeMap) rather than creating a new impl of the interface from scratch?

> large supercolumn deserialization invokes CSLM worst case scenario
> ------------------------------------------------------------------
>
>                 Key: CASSANDRA-1891
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-1891
>             Project: Cassandra
>          Issue Type: Improvement
>          Components: Core
>            Reporter: Cliff Moon
>            Priority: Minor
>             Fix For: 0.7.1
>
>         Attachments: supercolumn.patch
>
>
> SuperColumn deserialization hits a worst case insert scenario for CSLM: inserting pre-sorted
entries one at a time.  Inside of CSLM this requires scanning to the end of the list and doing
a comparison at every step for every item inserted.  This patch supplies a SortedMap interface
to the supercolumn deserialization.  CSLM will do a bulk insert from a SortedMap interface
supplied in the constructor.

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.


Mime
View raw message