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https://issues.apache.org/jira/browse/KAFKA-12559?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17432733#comment-17432733
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Aditya Upadhyaya commented on KAFKA-12559:
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[~ableegoldman]: thanks :) I'll go through the KIP process and revert back to 
you if I have any questions.

> Add a top-level Streams config for bounding off-heap memory
> -----------------------------------------------------------
>
>                 Key: KAFKA-12559
>                 URL: https://issues.apache.org/jira/browse/KAFKA-12559
>             Project: Kafka
>          Issue Type: Improvement
>          Components: streams
>            Reporter: A. Sophie Blee-Goldman
>            Assignee: Aditya Upadhyaya
>            Priority: Major
>              Labels: needs-kip, newbie, newbie++
>
> At the moment we provide an example of how to bound the memory usage of 
> rocskdb in the [Memory 
> Management|https://kafka.apache.org/27/documentation/streams/developer-guide/memory-mgmt.html#rocksdb]
>  section of the docs. This requires implementing a custom RocksDBConfigSetter 
> class and setting a number of rocksdb options for relatively advanced 
> concepts and configurations. It seems a fair number of users either fail to 
> find this or consider it to be for more advanced use cases/users. But RocksDB 
> can eat up a lot of off-heap memory and it's not uncommon for users to come 
> across a {{RocksDBException: Cannot allocate memory}}
> It would probably be a much better user experience if we implemented this 
> memory bound out-of-the-box and just gave users a top-level StreamsConfig to 
> tune the off-heap memory given to rocksdb, like we have for on-heap cache 
> memory with cache.max.bytes.buffering. More advanced users can continue to 
> fine-tune their memory bounding and apply other configs with a custom config 
> setter, while new or more casual users can cap on the off-heap memory without 
> getting their hands dirty with rocksdb.
> I would propose to add the following top-level config:
> rocksdb.max.bytes.off.heap: medium priority, default to -1 (unbounded), valid 
> values are [0, inf]
> I'd also want to consider adding a second, lower priority top-level config to 
> give users a knob for adjusting how much of that total off-heap memory goes 
> to the block cache + index/filter blocks, and how much of it is afforded to 
> the write buffers. I'm struggling to come up with a good name for this 
> config, but it would be something like
> rocksdb.memtable.to.block.cache.off.heap.memory.ratio: low priority, default 
> to 0.5, valid values are [0, 1]



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