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https://issues.apache.org/jira/browse/KAFKA-12559?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17432208#comment-17432208
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A. Sophie Blee-Goldman commented on KAFKA-12559:
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Seems like [~msundeq] is no longer working on this, so I've unassigned him
(Martin if you're still actively chipping away at this after all please
reassign yourself, or consider working out something with the other interested
people to share the workload)
[~adityau] feel free to get started on this if you're interested. This is going
to require a KIP, so I recommend reading up on the KIP process if you've never
done one before – otherwise, I look forward to seeing this KIP on the mailing
list :)
> 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: Martin Sundeqvist
> 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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