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https://issues.apache.org/jira/browse/KAFKA-8367?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Sophie Blee-Goldman updated KAFKA-8367:
---------------------------------------
    Comment: was deleted

(was: Actually, even if you are not using the ConfigSetter the BloomFilter 
object was also being leaked. There's a patch for this that should be available 
in 2.2.1)

> Non-heap memory leak in Kafka Streams
> -------------------------------------
>
>                 Key: KAFKA-8367
>                 URL: https://issues.apache.org/jira/browse/KAFKA-8367
>             Project: Kafka
>          Issue Type: Bug
>          Components: streams
>    Affects Versions: 2.2.0
>            Reporter: Pavel Savov
>            Priority: Major
>         Attachments: memory-prod.png, memory-test.png
>
>
> We have been observing a non-heap memory leak after upgrading to Kafka 
> Streams 2.2.0 from 2.0.1. We suspect the source to be around RocksDB as the 
> leak only happens when we enable stateful stream operations (utilizing 
> stores). We are aware of *KAFKA-8323* and have created our own fork of 2.2.0 
> and ported the fix scheduled for release in 2.2.1 to our fork. It did not 
> stop the leak, however.
> We are having this memory leak in our production environment where the 
> consumer group is auto-scaled in and out in response to changes in traffic 
> volume, and in our test environment where we have two consumers, no 
> autoscaling and relatively constant traffic.
> Below is some information I'm hoping will be of help:
>  * RocksDB Config:
> Block cache size: 4 MiB
> Write buffer size: 2 MiB
> Block size: 16 KiB
> Cache index and filter blocks: true
> Manifest preallocation size: 64 KiB
> Max write buffer number: 3
> Max open files: 6144
>  
>  * Memory usage in production
> The attached graph (memory-prod.png) shows memory consumption for each 
> instance as a separate line. The horizontal red line at 6 GiB is the memory 
> limit.
> As illustrated on the attached graph from production, memory consumption in 
> running instances goes up around autoscaling events (scaling the consumer 
> group either in or out) and associated rebalancing. It stabilizes until the 
> next autoscaling event but it never goes back down.
> An example of scaling out can be seen from around 21:00 hrs where three new 
> instances are started in response to a traffic spike.
> Just after midnight traffic drops and some instances are shut down. Memory 
> consumption in the remaining running instances goes up.
> Memory consumption climbs again from around 6:00AM due to increased traffic 
> and new instances are being started until around 10:30AM. Memory consumption 
> never drops until the cluster is restarted around 12:30.
>  
>  * Memory usage in test
> As illustrated by the attached graph (memory-test.png) we have a fixed number 
> of two instances in our test environment and no autoscaling. Memory 
> consumption rises linearly until it reaches the limit (around 2:00 AM on 
> 5/13) and Mesos restarts the offending instances, or we restart the cluster 
> manually.
>  
>  * No heap leaks observed
>  * Window retention: 2 or 11 minutes (depending on operation type)
>  * Issue not present in Kafka Streams 2.0.1
>  * No memory leak for stateless stream operations (when no RocksDB stores are 
> used)
>  



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