[jira] [Comment Edited] (FLINK-4094) Off heap memory deallocation might not properly work

["Maximilian Michels (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/FLINK-4094?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15399038#comment-15399038 ] 

Maximilian Michels edited comment on FLINK-4094 at 7/29/16 9:35 AM:
--------------------------------------------------------------------

I don't think just disallowing preallocation:false is a good fix. We should rather fix the underlying issue with the memory management and freeing of memory.

I can't asses the problem at the moment. As far as I know 'preallocation: false' never releases memory. It only acquires memory dynamically and returns it to the memory manager if it is not needed anymore. Only when shutting down the TaskManager the MemoryManager releases the acquired memory.

Please correct me if I'm wrong.


was (Author: mxm):
I don't think just disallowing preallocation:false is a good fix. We should rather fix the underlying issue with the memory management and freeing of memory.

I can't asses the problem at the moment. As far as I know 'preallocation' never releases memory. It only acquires memory dynamically and returns it to the memory manager if it is not needed anymore. Only when shutting down the TaskManager the MemoryManager releases the acquired memory.

Please correct me if I'm wrong.

> Off heap memory deallocation might not properly work
> ----------------------------------------------------
>
>                 Key: FLINK-4094
>                 URL: https://issues.apache.org/jira/browse/FLINK-4094
>             Project: Flink
>          Issue Type: Bug
>          Components: Local Runtime
>    Affects Versions: 1.1.0
>            Reporter: Till Rohrmann
>            Assignee: ramkrishna.s.vasudevan
>            Priority: Critical
>             Fix For: 1.1.0
>
>
> A user reported that off-heap memory is not properly deallocated when setting {{taskmanager.memory.preallocate:false}} (per default) [1]. This can cause the TaskManager process being killed by the OS.
> It should be possible to execute multiple batch jobs with preallocation turned off. No longer used direct memory buffers should be properly garbage collected so that the JVM process does not exceed it's maximum memory bounds.
> [1] http://apache-flink-mailing-list-archive.1008284.n3.nabble.com/offheap-memory-allocation-and-memory-leak-bug-td12154.html



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)