hbase-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "stack (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HBASE-4027) Enable direct byte buffers LruBlockCache
Date Mon, 25 Jul 2011 23:43:09 GMT

    [ https://issues.apache.org/jira/browse/HBASE-4027?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13070859#comment-13070859
] 

stack commented on HBASE-4027:
------------------------------

Doc is great.

These could be final:

+  private LruBlockCache onHeapCache;
+  private SlabCache offHeapCache;

Says 'Metrics are the combined size and hits and misses of both caches' but down in getStats
we seem to be getting onheap stats only.  Intentional?  Same for heapSize.

Do you want to leave this line in hfile? +      LOG.debug("decompressedSize = " + decompressedSize);

Whats it mean when you say 'An exception will be thrown if the cached data is larger than
the size of the allocated block'?

More notes later.

> Enable direct byte buffers LruBlockCache
> ----------------------------------------
>
>                 Key: HBASE-4027
>                 URL: https://issues.apache.org/jira/browse/HBASE-4027
>             Project: HBase
>          Issue Type: Improvement
>            Reporter: Jason Rutherglen
>            Assignee: Li Pi
>            Priority: Minor
>         Attachments: slabcachepatch.diff, slabcachepatchv2.diff, slabcachepatchv3.1.diff,
slabcachepatchv3.2.diff, slabcachepatchv3.diff, slabcachepatchv4.diff
>
>
> Java offers the creation of direct byte buffers which are allocated outside of the heap.
> They need to be manually free'd, which can be accomplished using an documented {{clean}}
method.
> The feature will be optional.  After implementing, we can benchmark for differences in
speed and garbage collection observances.

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

        

Mime
View raw message