[SERVER-55679] Remove wait for w:majority from donor shards generating minFetchTimestamp in resharding Created: 31/Mar/21 Updated: 29/Oct/23 Resolved: 02/Apr/21 |
|
| Status: | Closed |
| Project: | Core Server |
| Component/s: | Sharding |
| Affects Version/s: | None |
| Fix Version/s: | 5.0.0-rc0 |
| Type: | Task | Priority: | Major - P3 |
| Reporter: | Max Hirschhorn | Assignee: | Max Hirschhorn |
| Resolution: | Fixed | Votes: | 0 |
| Labels: | sharding-wfbf-day | ||
| Remaining Estimate: | Not Specified | ||
| Time Spent: | Not Specified | ||
| Original Estimate: | Not Specified | ||
| Issue Links: |
|
||||||||||||
| Backwards Compatibility: | Fully Compatible | ||||||||||||
| Sprint: | Sharding 2021-04-05 | ||||||||||||
| Participants: | |||||||||||||
| Linked BF Score: | 125 | ||||||||||||
| Story Points: | 1 | ||||||||||||
| Description |
|
The PrimaryOnlyService framework code guarantees that a PrimaryOnlyService::Instance does all of its writes under the same replication term. This naturally leads to the monotonic writes property. The monotonic writes property is sufficient here because the DonorStateEnum::kDonatingInitialData update can only become majority-committed if the no-op oplog entry to generate the minFetchTimestamp had also become majority-committed. This makes waiting for w:majority here unnecessary. And waiting for w:majority can be problematic because the timestamp to be pinned can end up lagging behind the current oldest_timestamp value and therefore become ineligible for pinning. |
| Comments |
| Comment by Githook User [ 02/Apr/21 ] |
|
Author: {'name': 'Max Hirschhorn', 'email': 'max.hirschhorn@mongodb.com', 'username': 'visemet'}Message: |