[ 
https://issues.apache.org/jira/browse/FLINK-18353?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17142077#comment-17142077
 ] 

Andrey Zagrebin commented on FLINK-18353:
-----------------------------------------

Alright, I think the solution with an additional option 
`jobmanager.memory.enable-direct-limit` will also work. If we see that users 
encounter a lot of direct OOM errors, we can set it to true by default.

> [1.11.0] maybe document jobmanager behavior change regarding 
> -XX:MaxDirectMemorySize
> ------------------------------------------------------------------------------------
>
>                 Key: FLINK-18353
>                 URL: https://issues.apache.org/jira/browse/FLINK-18353
>             Project: Flink
>          Issue Type: Improvement
>          Components: Documentation, Runtime / Configuration
>    Affects Versions: 1.11.0
>            Reporter: Steven Zhen Wu
>            Priority: Major
>
> I know FLIP-116 (Unified Memory Configuration for Job Managers) is introduced 
> in 1.11. That does cause a small behavior change regarding 
> `-XX:MaxDirectMemorySize`. Previously, jobmanager don't set JVM arg 
> `-XX:MaxDirectMemorySize`, which means JVM can use up to -`Xmx` size for 
> direct memory. Now `-XX:MaxDirectMemorySize` is always set to 
> [jobmanager.memory.off-heap.size|https://ci.apache.org/projects/flink/flink-docs-master/ops/config.html#jobmanager-memory-off-heap-size]
>  config (default 128 mb).
>  
> {{It is possible for jobmanager to get "java.lang.OufOfMemoryError: Direct 
> Buffer Memory" without tuning 
> }}{{[jobmanager.memory.off-heap.size|https://ci.apache.org/projects/flink/flink-docs-master/ops/config.html#jobmanager-memory-off-heap-size]}}
>  especially for high-parallelism jobs. Previously, no tuning needed.
>  
> Maybe we should point out the behavior change in the migration guide?
> [https://ci.apache.org/projects/flink/flink-docs-master/ops/memory/mem_migration.html#migrate-job-manager-memory-configuration]



--
This message was sent by Atlassian Jira
(v8.3.4#803005)

Reply via email to