[ 
https://issues.apache.org/jira/browse/FLINK-9558?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Flink Jira Bot updated FLINK-9558:
----------------------------------
    Labels: auto-deprioritized-major auto-unassigned stale-minor  (was: 
auto-deprioritized-major auto-unassigned)

I am the [Flink Jira Bot|https://github.com/apache/flink-jira-bot/] and I help 
the community manage its development. I see this issues has been marked as 
Minor but is unassigned and neither itself nor its Sub-Tasks have been updated 
for 180 days. I have gone ahead and marked it "stale-minor". If this ticket is 
still Minor, please either assign yourself or give an update. Afterwards, 
please remove the label or in 7 days the issue will be deprioritized.


> Memory leaks during usage of bucketing-sink with disabled checkpointing
> -----------------------------------------------------------------------
>
>                 Key: FLINK-9558
>                 URL: https://issues.apache.org/jira/browse/FLINK-9558
>             Project: Flink
>          Issue Type: Bug
>          Components: Connectors / FileSystem
>    Affects Versions: 1.3.0
>            Reporter: Rinat Sharipov
>            Priority: Minor
>              Labels: auto-deprioritized-major, auto-unassigned, stale-minor
>
> Hi mates, we have some Flink jobs, that are writing data from kafka into 
> hdfs, using Bucketing-Sink.
>  For some reasons, those jobs are running without checkpointing. For now, it 
> not a big problem for us, if some files are remained open in case of job 
> reloading.
>   
>  Periodically, those jobs fail with *OutOfMemory* exception, and seems, that 
> I found a strange thing in the implementation of BucketingSink.
>   
>  During the sink lifecycle, we have a state object, implemented as a map, 
> where key is a bucket path, and value is a state, that contains information 
> about opened files and list of pending files.
>  After researching of the heap dump, I found, that those state stores 
> information about ~ 1_000 buckets and their state, all this stuff weights ~ 
> 120 Mb.
>   
>  I’ve looked through the code, and found, that we removing the buckets from 
> the state, in *notifyCheckpointComplete* method. 
> {code:java}
> @Override
> public void notifyCheckpointComplete(long checkpointId) throws Exception {
>   Iterator<Map.Entry<String, BucketState<T>>> bucketStatesIt = 
> state.bucketStates.entrySet().iterator();
>   while (bucketStatesIt.hasNext()) {
>        if (!bucketState.isWriterOpen &&
>        bucketState.pendingFiles.isEmpty() &&
>        bucketState.pendingFilesPerCheckpoint.isEmpty()) {
>        // We've dealt with all the pending files and the writer for this 
> bucket is not currently open.
>        // Therefore this bucket is currently inactive and we can remove it 
> from our state.
>        bucketStatesIt.remove();
>     }
>     }
> }
> {code}
> So, this looks like an issue, when you are using this sink in checkpointless 
> environment, because the data always added to the state, but never removed.
>   
>  Of course, we could enable checkpointing, and use one of available backends, 
> but as for me, it seems like a non expected behaviour, like I have an 
> opportunity to run the job without checkpointing, but really, if I do so, I 
> got an exception in sink component.
> As for me, it seems, that we should at least document such behaviour, or 
> implement any fail-fast implementation, that wouldn't work in env with 
> disabled checkpointing
>  



--
This message was sent by Atlassian Jira
(v8.20.1#820001)

Reply via email to