[jira] [Commented] (HBASE-7612) [JDK8] Replace use of high-scale-lib counters with intrinsic facilities

[Duo Zhang (JIRA)]

    [ 
https://issues.apache.org/jira/browse/HBASE-7612?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15501898#comment-15501898
 ] 

Duo Zhang commented on HBASE-7612:
----------------------------------

I added the Deprecated annotation to Counter. We could remove it in the next 
major release I think?

And for sumThenReset, the only place is

{code:title=HFile.java}
  /**
   * Number of checksum verification failures. It also
   * clears the counter.
   */
  public static final long getChecksumFailuresCount() {
    return CHECKSUM_FAILURES.sumThenReset();
  }
{code}

And the original code is

{code:title=HFile.java}
  /**
   * Number of checksum verification failures. It also
   * clears the counter.
   */
  public static final long getChecksumFailuresCount() {
    long count = CHECKSUM_FAILURES.get();
    CHECKSUM_FAILURES.set(0);
    return count;
  }
{code}

I think the original implementation will also miss some updates so it is not 
very critical? And seems it is only used in testcase.

Thanks. [~enis]

> [JDK8] Replace use of high-scale-lib counters with intrinsic facilities
> -----------------------------------------------------------------------
>
>                 Key: HBASE-7612
>                 URL: https://issues.apache.org/jira/browse/HBASE-7612
>             Project: HBase
>          Issue Type: Sub-task
>          Components: metrics
>    Affects Versions: 2.0.0
>            Reporter: Andrew Purtell
>            Assignee: Duo Zhang
>            Priority: Trivial
>             Fix For: 2.0.0
>
>         Attachments: HBASE-7612-v1.patch, HBASE-7612.patch
>
>
> JEP155 introduces a few new classes (DoubleAccumulator, DoubleAdder, 
> LongAccumulator, LongAdder) that "internally employ contention-reduction 
> techniques that provide huge throughput improvements as compared to Atomic 
> variables". There are applications of these where we are currently using 
> Cliff Click's high-scale-lib and for metrics.
> See http://openjdk.java.net/jeps/155



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)