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Thomas Mueller commented on OAK-3071: ------------------------------------- Are we sure such a compound index will help for the condition we use (benchmark numbers)? As far as I understand the docs at http://docs.mongodb.org/manual/core/multikey-index-bounds/ , a compound index will not help much here. > Add a compound index for _modified + _id > ---------------------------------------- > > Key: OAK-3071 > URL: https://issues.apache.org/jira/browse/OAK-3071 > Project: Jackrabbit Oak > Issue Type: Improvement > Components: mongomk > Reporter: Chetan Mehrotra > Fix For: 1.2.3, 1.3.4, 1.0.17 > > > As explained in OAK-1966 diff logic makes a call like > bq. db.nodes.find({ _id: { $gt: "3:/content/foo/01/", $lt: > "3:/content/foo010" }, _modified: { $gte: 1405085300 } }).sort({_id:1}) > For better and deterministic query performance we would need to create a > compound index like \{_modified:1, _id:1\}. This index would ensure that > Mongo does not have to perform object scan while evaluating such a query. > Care must be taken that index is only created by default for fresh setup. For > existing setup we should expose a JMX operation which can be invoked by > system admin to create the required index as per maintenance window -- This message was sent by Atlassian JIRA (v6.3.4#6332)