Yingqi Lu created CASSANDRA-13903:
-------------------------------------
Summary: Add JDK9 vectorizedMismatch array compare support
Key: CASSANDRA-13903
URL: https://issues.apache.org/jira/browse/CASSANDRA-13903
Project: Cassandra
Issue Type: Improvement
Components: Local Write-Read Paths
Reporter: Yingqi Lu
Dear All,
JDK9 has recently been released (http://openjdk.java.net/projects/jdk9/). It
introduces a set of new vectorizedMismatch APIs for array comparison. On
supported platforms, the new JDK9 implementation is intrisified to leverage
SIMD instructions. For a byte array comparison, up to 64 bytes (512 bits) can
be compared as a single unit.
Currently in Cassandra, keys are implemented as ByteBuffers and compared as
byte arrays most of the time. Key comparison, for example decorated key
compare, it is either done with unsafe operation taking 8 bytes at a time, or
pure java operation comparing byte by byte. This can be optimized with new JDK9
java.util.Arrays.compare APIs on modern CPUs.
Please let us know your feedback. At the meantime, we will submit a patch with
performance studies in couple of weeks.
Thanks,
Yingqi Lu
--
This message was sent by Atlassian JIRA
(v6.4.14#64029)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
