[OAK-1417] Processing pending observation events does not scale linearly with the number of events

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.17
• Component/s: mongomk, segmentmk
• Assignee: Michael Dürig
• Reporter: Michael Dürig
• Created: 11/Feb/14 16:49
• Updated: 27/Feb/14 09:28
• Resolved: 18/Feb/14 11:59

Description

org.apache.jackrabbit.oak.jcr.LargeOperationIT#largeNumberOfPendingEvents does not scale linearly. Neither on a segment nor on a document node store. This test asserts that the number of pending observation events (e.g. due to a large commit or cluster sync) has a linear processing time. That is the time it takes to process one such event is independent of the total number of events.

seg quotients: 0.24215928530697586, 0.4065934065934066, 1.7548262548262548, 0.6892189218921893, 1.2083000798084598
doc quotients: 0.2990824434780629, 0.14113885505481122, 0.587378640776699, 1.3122130394857667, 142.65850244926523

While in the case of the segment node store the numbers do not seem too worrisome, the document node store seems to start lagging behind badly as soon as there are more than 32768 pending events.

See OAK-1413 for how to read those numbers.