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Andrzej Bialecki commented on NUTCH-628: ----------------------------------------- Not everything looks like a String ;) MapWritable is useful in situations where you need to (de)serialize non-String types. And most of the information in HostDb is numeric, so if we decided to use simple Metadata it would cause constant pointless conversion from/to Strings. Having said that, I'm for a specialized class (which can contain MapWritable as a placeholder for anything else than the specific built-in types of info). > Host database to keep track of host-level information > ----------------------------------------------------- > > Key: NUTCH-628 > URL: https://issues.apache.org/jira/browse/NUTCH-628 > Project: Nutch > Issue Type: New Feature > Components: fetcher, generator > Reporter: Otis Gospodnetic > Attachments: NUTCH-628-DomainStatistics.patch, NUTCH-628-HostDb.patch > > > Nutch would benefit from having a DB with per-host/domain/TLD information. > For instance, Nutch could detect hosts that are timing out, store information > about that in this DB. Segment/fetchlist Generator could then skip such > hosts, so they don't slow down the fetch job. Another good use for such a DB > is keeping track of various host scores, e.g. spam score. > From the recent thread on [EMAIL PROTECTED]: > Otis asked: > > While we are at it, how would one go about implementing this DB, as far as > > its structures go? > Andrzej said: > The easiest I can imagine is to use something like <Text, MapWritable>. > This way you could store arbitrary information under arbitrary keys. > I.e. a single database then could keep track of aggregate statistics at > different levels, e.g. TLD, domain, host, ip range, etc. The basic set > of statistics could consist of a few predefined gauges, totals and averages. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.