You are viewing a plain text version of this content. The canonical link for it is here.
Posted to commits@cassandra.apache.org by "Benedict (JIRA)" <ji...@apache.org> on 2018/11/30 13:51:00 UTC
[jira] [Comment Edited] (CASSANDRA-14832) BufferPool: allocating
thread for new chunks should acquire directly
[ https://issues.apache.org/jira/browse/CASSANDRA-14832?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16704755#comment-16704755 ]
Benedict edited comment on CASSANDRA-14832 at 11/30/18 1:50 PM:
----------------------------------------------------------------
Thanks! Committed as [d8164c643395e3b6579a2fe6ce6ff0423df2f520|https://github.com/apache/cassandra/commit/d8164c643395e3b6579a2fe6ce6ff0423df2f520] (to trunk only, since this isn't really important enough to push to 3.x IMO)
For future reference, a few helpful things to do to ease the commit burden:
* update CHANGES.txt with the title of the JIRA
* sign the commit message with "patch by Jon Meredith; reviewed by Benedict for CASSANDRA-14832"
* post a link to your CI run
was (Author: benedict):
Thanks! Committed as [d8164c643395e3b6579a2fe6ce6ff0423df2f520|https://github.com/apache/cassandra/commit/d8164c643395e3b6579a2fe6ce6ff0423df2f520]
For future reference, a few helpful things to do to ease the commit burden:
* update CHANGES.txt with the title of the JIRA
* sign the commit message with "patch by Jon Meredith; reviewed by Benedict for CASSANDRA-14832"
* post a link to your CI run
> BufferPool: allocating thread for new chunks should acquire directly
> --------------------------------------------------------------------
>
> Key: CASSANDRA-14832
> URL: https://issues.apache.org/jira/browse/CASSANDRA-14832
> Project: Cassandra
> Issue Type: Improvement
> Components: Core
> Reporter: Jon Meredith
> Assignee: Jon Meredith
> Priority: Minor
> Fix For: 4.0
>
>
> When BufferPool does not have any free Chunks to satisfy a request, the calling thread allocates a new large block of memory which it breaks up into chunks and adds to the free chunks queue, then pulls from the queue to satisfy it's own allocation.
> If enough other threads request chunks it is possible for the queue to be exhausted before the original allocating thread is able to pull of it's own allocation, causing the original allocator to loop and attempt to allocate more memory. This is unfair to the original caller and may cause it to block on a system call to allocate more memory.
> Instead of the current behavior, allocateMoreChunks could hold back one of the chunks and return it to the caller instead so that it will at most call allocate once.
>
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
---------------------------------------------------------------------
To unsubscribe, e-mail: commits-unsubscribe@cassandra.apache.org
For additional commands, e-mail: commits-help@cassandra.apache.org