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https://issues.apache.org/jira/browse/CASSANDRA-8614?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14276400#comment-14276400
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Ariel Weisberg commented on CASSANDRA-8614:
-------------------------------------------

I checked Netty's PlatformDependent for how they did it and copied that. The 
question would be why they did it that way? Maybe to avoid error prone string 
parsing? I m fine with switching to parsing the java.version string.

> 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
>              Labels: performance
>         Attachments: 8614.patch
>
>
> 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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