[
https://issues.apache.org/jira/browse/COMPRESS-285?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14096804#comment-14096804
]
Stefan Bodewig commented on COMPRESS-285:
-----------------------------------------
svn revision 1617904
docs are missing and I'm not sure how to test this properly.
I've merged the two AtomicBooleans from Wojciech's idea into a single
AtomicInteger and immediately check for XZ's presence if caching is enabled to
avoid race conditions.
> checking of availability of XZ compression is expensive - result should be
> reused
> ---------------------------------------------------------------------------------
>
> Key: COMPRESS-285
> URL: https://issues.apache.org/jira/browse/COMPRESS-285
> Project: Commons Compress
> Issue Type: Improvement
> Components: Compressors
> Affects Versions: 1.5, 1.6, 1.7, 1.8
> Environment: linux 64-bit, java 7, glassfish, solr, tika
> Reporter: Wojciech Łozowicki
> Priority: Minor
> Labels: XZ, performance
> Fix For: 1.9
>
>
> I use solr with apache tika for indexing documents. Tika uses
> commons-compress to handle compressed files. Using sampler (jvisualvm) I have
> seen that quite a lot of time (5-7%) during my tests is spent in
> XZUtils.isXZCompressionAvailable because of unavailable XZ compression (I
> guess for each time classloaders spend some time looking for unavailable
> classes, then NoClassDefFoundError).
> I think the result of the first check should be stored and reused.
> Here is the stacktrace (just to show the way tika is using commons-compress):
> org.apache.commons.compress.compressors.xz.XZUtils.isXZCompressionAvailable(XZUtils.java:52)
> at
> org.apache.commons.compress.compressors.CompressorStreamFactory.createCompressorInputStream(CompressorStreamFactory.java:140)
> at
> org.apache.tika.parser.pkg.ZipContainerDetector.detectCompressorFormat(ZipContainerDetector.java:95)
> at
> org.apache.tika.parser.pkg.ZipContainerDetector.detect(ZipContainerDetector.java:81)
> at
> org.apache.tika.detect.CompositeDetector.detect(CompositeDetector.java:61)
--
This message was sent by Atlassian JIRA
(v6.2#6252)
