[
https://issues.apache.org/jira/browse/CASSANDRA-8614?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14337918#comment-14337918
]
Alexandre Dutra commented on CASSANDRA-8614:
--------------------------------------------
If I'm not mistaken it should still be possible to build/run Cassandra 3.0 with
JDK7.
However in {{CRC32Factory}} there is a call to
{{java.util.zip.CRC32#update(java.nio.ByteBuffer)}}.
This method has been introduced in Java 8. As a consequence It's currently
impossible to build the trunk with JDK7.
> 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: Ariel Weisberg
> Labels: performance
> Attachments: 8614.patch, CRC32.class, 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.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
