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Bob Dionne commented on COUCHDB-1288: ------------------------------------- Filipe, I started reviewing this and it looks good so far. There's an edge case we ran into the other day that @davisp and @kocolosk ran down. When you have `feed=continuous` and a hearbeat and a filter function that fail enough, the heartbeat timeout never triggers and no changes are sent. It's easy to reproduce, you can see how it's handled in fabric[1]. I can probably add it to this patch or open a second ticket if you prefer. Also, as an aside the `couch_changes:get_changes_timeout` is slightly awkward in the way heartbeat is handled. It appears to allow `heartbeat=true` and in that case defaults to the timeout in the config. That certainly does not agree with the documented semantics. Cheers, Bob [1] https://github.com/cloudant/fabric/commit/f9eea28e62496afcb > More efficient builtin filters _doc_ids and _design > --------------------------------------------------- > > Key: COUCHDB-1288 > URL: https://issues.apache.org/jira/browse/COUCHDB-1288 > Project: CouchDB > Issue Type: Improvement > Reporter: Filipe Manana > Attachments: couchdb_1288_2.patch, couchdb_1288_3.patch > > > We have the _doc_ids and _design _changes filter as of CouchDB 1.1.0. > While they meet the expectations of applications/users, they're far from > efficient for large databases. > Basically the implementation folds the entire seq btree and then filters > values by the document's ID, causing too much IO and busting caches. This > makes replication by doc IDs not so efficient as it could be. > The proposed patch avoids this by doing direct lookups in the ID btree, for > _doc_ids, and ranged fold for _design. > If there are no objections, I would apply to branch 1.2.x besides -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira