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 Elliott Smith (Jira)" <ji...@apache.org> on 2019/11/08 14:50:00 UTC
[jira] [Comment Edited] (CASSANDRA-15367) Memtable memory
allocations may deadlock
[ https://issues.apache.org/jira/browse/CASSANDRA-15367?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16970245#comment-16970245 ]
Benedict Elliott Smith edited comment on CASSANDRA-15367 at 11/8/19 2:49 PM:
-----------------------------------------------------------------------------
patches available:
||Branch||Tests||
|[3.0|https://github.com/belliottsmith/cassandra/tree/15367-3.0]|[circleci|https://circleci.com/workflow-run/7bab1194-44d7-49e4-bb04-6fe809657065]|
|[3.11|https://github.com/belliottsmith/cassandra/tree/15367-3.11]|[circleci|https://circleci.com/workflow-run/85e153ff-fda0-4d12-929a-b56ffa67ba16]|
|[4.0|https://github.com/belliottsmith/cassandra/tree/15367-4.0]|[circleci|https://circleci.com/workflow-run/3bda14eb-76f0-45c3-99c4-4abe2ea9c34a]|
was (Author: benedict):
patches available:
||Branch||Tests||
|https://github.com/belliottsmith/cassandra/tree/15367-3.0|https://circleci.com/workflow-run/7bab1194-44d7-49e4-bb04-6fe809657065|
|https://github.com/belliottsmith/cassandra/tree/15367-3.11|https://circleci.com/workflow-run/85e153ff-fda0-4d12-929a-b56ffa67ba16|
|https://github.com/belliottsmith/cassandra/tree/15367-4.0|https://circleci.com/workflow-run/3bda14eb-76f0-45c3-99c4-4abe2ea9c34a|
> Memtable memory allocations may deadlock
> ----------------------------------------
>
> Key: CASSANDRA-15367
> URL: https://issues.apache.org/jira/browse/CASSANDRA-15367
> Project: Cassandra
> Issue Type: Bug
> Components: Local/Commit Log, Local/Memtable
> Reporter: Benedict Elliott Smith
> Assignee: Benedict Elliott Smith
> Priority: Normal
> Fix For: 4.0, 2.2.x, 3.0.x, 3.11.x
>
>
> * Under heavy contention, we guard modifications to a partition with a mutex, for the lifetime of the memtable.
> * Memtables block for the completion of all {{OpOrder.Group}} started before their flush began
> * Memtables permit operations from this cohort to fall-through to the following Memtable, in order to guarantee a precise commitLogUpperBound
> * Memtable memory limits may be lifted for operations in the first cohort, since they block flush (and hence block future memory allocation)
> With very unfortunate scheduling
> * A contended partition may rapidly escalate to a mutex
> * The system may reach memory limits that prevent allocations for the new Memtable’s cohort (C2)
> * An operation from C2 may hold the mutex when this occurs
> * Operations from a prior Memtable’s cohort (C1), for a contended partition, may fall-through to the next Memtable
> * The operations from C1 may execute after the above is encountered by those from C2
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
---------------------------------------------------------------------
To unsubscribe, e-mail: commits-unsubscribe@cassandra.apache.org
For additional commands, e-mail: commits-help@cassandra.apache.org