[ http://issues.apache.org/jira/browse/NUTCH-415?page=comments#action_12458814 ] Sami Siren commented on NUTCH-415: ----------------------------------
Please also consider the performance implications. If this marking will add signifigant performance overhead then it would be good to made it optional. > Generate should mark selected records in crawlDB > ------------------------------------------------ > > Key: NUTCH-415 > URL: http://issues.apache.org/jira/browse/NUTCH-415 > Project: Nutch > Issue Type: Bug > Affects Versions: 0.8, 0.9.0, 0.8.1, 0.8.2 > Reporter: Andrzej Bialecki > Assigned To: Andrzej Bialecki > Fix For: 0.8.2, 0.9.0 > > > In Nutch 0.7.x, if user ran "generate" twice without intervening "updatedb", > each fetchlist would be different, because "generate" would mark selected > entries as "being fetched" (by moving their fetch time one week forward). > In Nutch 0.8 and later, crawldb is not modified at all during "generate". > This means that two "generate"-s run without intervening "updatedb" will > create exactly the same fetchlists, which is undesirable. > I propose to re-implement this feature, using the same mechanism. CrawlDB > update would be performed simultaneously with the first mapred job in > Generator, and a modified crawldb content would be produced together with an > (unsorted) fetchlist in Selector, using a custom OutputFormat (patches to > follow ;) ). Additionally, to ensure that correct version of modified crawldb > is installed, I propose to add a locking mechanism, which prevents from > running two processes that modify crawldb simultaneously. -- 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 ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Nutch-developers mailing list Nutch-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/nutch-developers
