[OAK-6789] RDB: RevisionGC performance on Oracle

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.7.10, 1.6.7, 1.8.0
• Component/s: rdbmk
• Epic Link: RDB Support
• Assignee: Julian Reschke
• Reporter: Julian Reschke
• Created: 06/Oct/17 11:24
• Updated: 06/Nov/19 12:16
• Resolved: 12/Oct/17 09:50

Description

In RevisionGC on Oracle, performance of deletes is bad. Using RevisionGCTest:

VersionGCStats{ignoredGCDueToCheckPoint=false, canceled=false, deletedDocGCCount=92092 (of which leaf: 92000), updateResurrectedGCCount=0, splitDocGCCount=1, intermediateSplitDocGCCount=0, iterationCount=2, timeActive=7.429 min, timeToCollectDeletedDocs=1394 ms, timeToCheckDeletedDocs=250.4 ms, timeToSortDocIds=374.0 us, timeTakenToUpdateResurrectedDocs=17.00 us, timeTakenToDeleteDeletedDocs=7.399 min, timeTakenToCollectAndDeleteSplitDocs=97.95 ms}
Performed RevisionGC in 7,429 min

Compared with DB2:

VersionGCStats{ignoredGCDueToCheckPoint=false, canceled=false, deletedDocGCCount=96096 (of which leaf: 96000), updateResurrectedGCCount=0, splitDocGCCount=1, intermediateSplitDocGCCount=0, iterationCount=2, timeActive=8.240 s, timeToCollectDeletedDocs=1780 ms, timeToCheckDeletedDocs=259.7 ms, timeToSortDocIds=237.0 us, timeTakenToUpdateResurrectedDocs=19.00 us, timeTakenToDeleteDeletedDocs=4.552 s, timeTakenToCollectAndDeleteSplitDocs=685.4 ms}
Performed RevisionGC in 8,243 s

Issue Links

• is blocked by: OAK-6811 BasicDocumentStore: avoid use of API edge case in test of cache invalidation
• is related to: OAK-6797 DocumentStore conditional remove: EXISTS on non-revision property?