[OAK-2392] [DocumentMK] Garbage Collect older revisions of binary properties in main document

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 1.5.1, 1.6.0
• Component/s: mongomk
• Epic Link: DocumentMK revision GC
• Assignee: Marcel Reutegger
• Reporter: Chetan Mehrotra
• Created: 13/Jan/15 06:01
• Updated: 01/Dec/16 09:06
• Resolved: 05/Apr/16 08:49

Description

Current GC logic for DocumentMK only collects certain types of garbage (see OAK-1981) and currently only split documents are removed. While complete full blow gc would take time and yet not fully implemented we should handle those documents which have binary properties and those properties get updated few times (but not very frequently).

For e.g. performing a reindex for Lucene index would lead to removal of index files nodes and again creation of nodes with same name. In such a case the older revision of binary property would remain in main document and would not be eligible for gc as per current impl.

As a fix the GC logic should look for document which might have binaries and then remove the older revisions of binary properties. Currently we do scan all such documents for Blob GC.

So this can be done either as part of Revision GC or Blob GC

Issue Links

• blocks: OAK-1981 Implement full scale Revision GC for DocumentNodeStore
• is related to: OAK-5010 Document split with binary properties too eager
• is related to: OAK-5205 Lucene index causes many split documents
• is related to: OAK-3712 Clean up uncommitted changes