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https://issues.apache.org/jira/browse/KAFKA-10470?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17217626#comment-17217626
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James Yuzawa commented on KAFKA-10470:
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The maintainer of zstd-jni seems to be back from vacation, so I was going to
inquire more about what they think about adding more buffering on that linked
github issue above. I'm finding the performance hits are occurring when Kafka
writes a few bytes at a time typically from ByteUtils class when using the
ZstdOutputStream. I also found that the ZstdInputStream has the same
performance hit when reading a few bytes at a time. As a stopgap solution, we
could add a BufferedOutputStream and BufferedInputStream like it is done for
GZIP:
[https://github.com/apache/kafka/blob/trunk/clients/src/main/java/org/apache/kafka/common/record/CompressionType.java#L57]
[https://github.com/apache/kafka/blob/trunk/clients/src/main/java/org/apache/kafka/common/record/CompressionType.java#L69]
but in the zstd enum value
[https://github.com/apache/kafka/blob/trunk/clients/src/main/java/org/apache/kafka/common/record/CompressionType.java#L118]
This would help but at the cost of not being able to reuse the internal buffers
within the BufferedOutputStream and and BufferedInputStream.
> zstd decompression with small batches is slow and causes excessive GC
> ---------------------------------------------------------------------
>
> Key: KAFKA-10470
> URL: https://issues.apache.org/jira/browse/KAFKA-10470
> Project: Kafka
> Issue Type: Bug
> Affects Versions: 2.5.1
> Reporter: Robert Wagner
> Priority: Major
>
> Similar to KAFKA-5150 but for zstd instead of LZ4, it appears that a large
> decompression buffer (128kb) created by zstd-jni per batch is causing a
> significant performance bottleneck.
> The next upcoming version of zstd-jni (1.4.5-7) will have a new constructor
> for ZstdInputStream that allows the client to pass its own buffer. A similar
> fix as [PR #2967|https://github.com/apache/kafka/pull/2967] could be used to
> have the ZstdConstructor use a BufferSupplier to re-use the decompression
> buffer.
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