[ 
https://issues.apache.org/jira/browse/LUCENE-5416?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13882919#comment-13882919
 ] 

Paul Elschot commented on LUCENE-5416:
--------------------------------------

The last benchmark output is here: 
https://github.com/PaulElschot/lucene-solr/commit/772b55ad3c3d94752b37aa81b2e96cb50b321cf6
 ,
see from line 313 in this output, the comparisons and loads are given in 10log 
numbers.

In short:
- for advance() this is a factor of 1.7 to 4 times faster, and
- for nextDoc() this is up to 2.5 times faster, but for load factors higher 
than about 0.25 it is up to about 5 times slower.

> Performance of a FixedBitSet variant that uses Long.numberOfTrailingZeros()
> ---------------------------------------------------------------------------
>
>                 Key: LUCENE-5416
>                 URL: https://issues.apache.org/jira/browse/LUCENE-5416
>             Project: Lucene - Core
>          Issue Type: Bug
>          Components: core/search
>    Affects Versions: 5.0
>            Reporter: Paul Elschot
>            Priority: Minor
>             Fix For: 5.0
>
>
> On my machine the current byte index used in OpenBitSetIterator is slower 
> than Long.numberOfTrailingZeros() for advance().
> The pull request contains the code for benchmarking this taken from an early 
> stage of DocBlocksIterator.
> In case the benchmark shows improvements on more machines, well, we know what 
> to do...



--
This message was sent by Atlassian JIRA
(v6.1.5#6160)

---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]

Reply via email to