[ http://issues.apache.org/jira/browse/NUTCH-395?page=comments#action_12448795 ] Sami Siren commented on NUTCH-395: ----------------------------------
>>have you measured what made the biggest impact on performance - changes to >>Metadata, or >>changes to IO in FetcherOutput? >did not have time yet, I would quess that IO changes make most signifigant >part. After more digging my initial guess might not have been correct. By not touching IO at all I am able to get same improvement changing the trunk when comparing to nightly builds as I reported before on 0.8 branch. This is good, because we don't need to change file formats at all. > Increase fetching speed > ----------------------- > > Key: NUTCH-395 > URL: http://issues.apache.org/jira/browse/NUTCH-395 > Project: Nutch > Issue Type: Improvement > Components: fetcher > Affects Versions: 0.8.1 > Reporter: Sami Siren > Assigned To: Sami Siren > Attachments: nutch-0.8-performance.txt > > > There have been some discussion on nutch mailing lists about fetcher being > slow, this patch tried to address that. the patch is just a quich hack and > needs some cleaning up, it also currently applies to 0.8 branch and not trunk > and it has also not been tested in large. What it changes? > Metadata - the original metadata uses spellchecking, new version does not (a > decorator is provided that can do it and it should perhaps be used where http > headers are handled but in most of the cases the functionality is not > required) > Reading/writing various data structures - patch tries to do io more > efficiently see the patch for details. > Initial benchmark: > A small benchmark was done to measure the performance of changes with a > script that basically does the following: > -inject a list of urls into a fresh crawldb > -create fetchlist (10k urls pointing to local filesystem) > -fetch > -updatedb > original code from 0.8-branch: > real 10m51.907s > user 10m9.914s > sys 0m21.285s > after applying the patch > real 4m15.313s > user 3m42.598s > sys 0m18.485s -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ Nutch-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/nutch-developers
