[ http://issues.apache.org/jira/browse/NUTCH-61?page=comments#action_12368051 ]
Andrzej Bialecki commented on NUTCH-61: ---------------------------------------- I contemplated this for a while, and then decided against it. The main reason was that currently most of the "pluggable" extensions that result in running a single selected plugin are handled using a simple Factory pattern; as opposed to ChainedFilter pattern, where we use extension points. I guess the original reason was that implementations would almost always consist of a single class, so it didn't make sense to complicate it and require the whole plugin infrastructure ... It would be the same in this case (just a single class), so I followed the same pattern. It's easy to change this to use an extension point, if people prefer it this way. > Adaptive re-fetch interval. Detecting umodified content > ------------------------------------------------------- > > Key: NUTCH-61 > URL: http://issues.apache.org/jira/browse/NUTCH-61 > Project: Nutch > Type: New Feature > Components: fetcher > Reporter: Andrzej Bialecki > Assignee: Andrzej Bialecki > Attachments: 20050606.diff, 20051230.txt, 20060227.txt > > Currently Nutch doesn't adjust automatically its re-fetch period, no matter > if individual pages change seldom or frequently. The goal of these changes is > to extend the current codebase to support various possible adjustments to > re-fetch times and intervals, and specifically a re-fetch schedule which > tries to adapt the period between consecutive fetches to the period of > content changes. > Also, these patches implement checking if the content has changed since last > fetching; protocol plugins are also changed to make use of this information, > so that if content is unmodified it doesn't have to be fetched and processed. -- 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
