Stephan Ewen created FLINK-1442:
-----------------------------------

             Summary: Archived Execution Graph consumes too much memory
                 Key: FLINK-1442
                 URL: https://issues.apache.org/jira/browse/FLINK-1442
             Project: Flink
          Issue Type: Bug
          Components: JobManager
    Affects Versions: 0.9
            Reporter: Stephan Ewen


The JobManager archives the execution graphs, for analysis of jobs. The graphs 
may consume a lot of memory.

Especially the execution edges in all2all connection patterns are extremely 
many and add up in memory consumption.

The execution edges connect all parallel tasks. So for a all2all pattern 
between n and m tasks, there are n*m edges. For parallelism of multiple 100 
tasks, this can easily reach 100k objects and more, each with a set of metadata.

I propose the following to solve that:

1.  Clear all execution edges from the graph (majority of the memory consumers) 
when it is given to the archiver.

2. Have the map/list of the archived graphs behind a soft reference, to it will 
be removed under memory pressure before the JVM crashes. That may remove graphs 
from the history early, but is much preferable to the JVM crashing, in which 
case the graph is lost as well...

3. Long term: The graph should be archived somewhere else. Somthing like the 
History server used by Hadoop and Hive would be a good idea.




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

Reply via email to