MongoDB Storage (aka "MongoMK") and RDBMK:
Revision GC:
12.09.2015 00:00:00.857 *INFO* [pool-7-thread-10] org.apache.jackrabbit.oak.plugins.document.VersionGarbageCollector Starting revision garbage collection. Revisions older than [2015-09-11 00:00:00.857] would be removed
13.09.2015 00:00:15.912 *INFO* [pool-7-thread-9] org.apache.jackrabbit.oak.plugins.document.VersionGarbageCollector Iterated through 10000 documents so far. 9698 found to be deleted
14.09.2015 00:00:49.358 *INFO* [pool-7-thread-12] org.apache.jackrabbit.oak.plugins.document.VersionGarbageCollector Deleted 859050 (58.28%) documents so far
12.09.2015 00:39:43.490 *INFO* [pool-7-thread-10] org.apache.jackrabbit.oak.plugins.document.VersionGarbageCollector Version garbage collected in 39.71 min. VersionGCStats{ignoredGCDueToCheckPoint=false, deletedDocGCCount=180021, splitDocGCCount=4853, intermediateSplitDocGCCount=441, timeToCollectDeletedDocs=14.62 min, timeTakenToDeleteDocs=23.52 min}