[SERVER-75790] ShardServerOpObserver does not correctly identify if it's acting as primary or secondary Created: 06/Apr/23 Updated: 29/Oct/23 Resolved: 11/Apr/23 |
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| Status: | Closed |
| Project: | Core Server |
| Component/s: | None |
| Affects Version/s: | 5.0.0, 6.0.0 |
| Fix Version/s: | 7.0.0-rc0 |
| Type: | Bug | Priority: | Major - P3 |
| Reporter: | Jordi Serra Torrens | Assignee: | Jordi Serra Torrens |
| Resolution: | Fixed | Votes: | 0 |
| Labels: | None | ||
| Remaining Estimate: | Not Specified | ||
| Time Spent: | Not Specified | ||
| Original Estimate: | Not Specified | ||
| Issue Links: |
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| Backwards Compatibility: | Fully Compatible | ||||
| Operating System: | ALL | ||||
| Sprint: | Sharding EMEA 2023-04-17 | ||||
| Participants: | |||||
| Linked BF Score: | 146 | ||||
| Description |
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ShardServerOpObserver uses `isStandaloneOrPrimary` to identify if the observed write was done by this node itself (i.e. primary) or from secondary oplog application. However, the implementation of `isStandaloneOrPrimary` is flawed: It uses ReplicationCoordinator::getMemberState, which turns RS_PRIMARY as soon as the node wins the election. However, the newly-elected node may still be draining oplog. In that situation, the observer should still behave in "secondary" mode. The correct way to implement `isStandaloneOrPrimary` is to use ReplicationCoordinator::canAcceptWritesFor (which other op_observers already use). `canAcceptWritesFor` will only turn true after oplog has been drained. |
| Comments |
| Comment by Githook User [ 11/Apr/23 ] |
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Author: {'name': 'Jordi Serra Torrens', 'email': 'jordi.serra-torrens@mongodb.com', 'username': 'jordist'}Message: |