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https://issues.apache.org/jira/browse/CASSANDRA-8614?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14277347#comment-14277347
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Robert Stupp commented on CASSANDRA-8614:
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The intrinsic is definitely not present in Java 7. zlib used in JDK8 is quite
old (2010) - and support for Intel-CPU-CRC has been added to [zlib mid 2014
|https://github.com/jtkukunas/zlib/blob/master/crc_folding.c]. Maybe a newer
zlib via ld_preload?
> Select optimal CRC32 implementation at runtime
> ----------------------------------------------
>
> Key: CASSANDRA-8614
> URL: https://issues.apache.org/jira/browse/CASSANDRA-8614
> Project: Cassandra
> Issue Type: Improvement
> Components: Core
> Reporter: Ariel Weisberg
> Assignee: Benedict
> Labels: performance
> Attachments: 8614.patch, Sample.java
>
>
> JDK 8 has support for an intrinsic for CRC32 that runs at 12-13 gigabytes/sec
> per core in my quick and dirty test. PureJavaCRC32 is < 800 megabytes/sec if
> I recall and it has a lookup table that evicts random cache lines every time
> it runs.
> In order to capture the benefit of that when it is available we can select a
> CRC32 implementation at startup in a static block.
> If JDK 8 is not what is running we can fall back to the existing
> PureJavaCRC32 implementation.
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