[OAK-2592] Commit does not ensure w:majority

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.0, 1.2
• Fix Version/s: 1.3.14, 1.4
• Component/s: core, mongomk
• Labels: resilience
• Epic Link: DocumentMK resilience
• Assignee: Marcel Reutegger
• Reporter: Marcel Reutegger
• Created: 09/Mar/15 09:38
• Updated: 16/Feb/21 09:53
• Resolved: 07/Jan/16 10:05

Description

The MongoDocumentStore uses findAndModify() to commit a transaction. This operation does not allow an application specified write concern and always uses the MongoDB default write concern Acknowledged. This means a commit may not make it to a majority of a replica set when the primary fails. From a MongoDocumentStore perspective it may appear as if a write was successful and later reverted. See also the test in OAK-1641.

To fix this, we'd probably have to change the MongoDocumentStore to avoid findAndModify() and use update() instead.

Issue Links

• is related to: OAK-1453 MongoMK failover support for replica sets (esp. shards)
• is related to: OAK-3554 Use write concern of w:majority when connected to a replica set