[SERVER-47006] Implement a downgrade floor between 4.4 and 4.2 Created: 20/Mar/20 Updated: 29/Oct/23 Resolved: 02/Apr/20 |
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| Status: | Closed |
| Project: | Core Server |
| Component/s: | Storage |
| Affects Version/s: | None |
| Fix Version/s: | 4.2.6, 4.4.0-rc0, 4.7.0 |
| Type: | Improvement | Priority: | Major - P3 |
| Reporter: | Alexander Gorrod | Assignee: | Daniel Gottlieb (Inactive) |
| 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 | ||||||||||||||||||||
| Sprint: | Execution Team 2020-03-23, Execution Team 2020-04-06 | ||||||||||||||||||||
| Participants: | |||||||||||||||||||||
| Linked BF Score: | 50 | ||||||||||||||||||||
| Description |
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We have realized that we need a downgrade floor, because it's possible that multi-shard multi-document transactions will generate data that existing versions of MongoDB 4.2 won't be able to read. We are planning to increment the WiredTiger compatibility version in MongoDB 4.2 from 3.2.2 to 3.3.0 in We need to set compatibility=(release=3.2) to make sure that MongoDB 4.2 keeps producing log files in a format that older releases understand. We need to set compatibility=(requires_max=3.3) to allow the 4.2 release after this change is included to open a database generated by 4.4 (after it's had a clean shutdown). There is a related but orthogonal change in |
| Comments |
| Comment by Githook User [ 02/Apr/20 ] |
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Author: {'name': 'Daniel Gottlieb', 'email': 'daniel.gottlieb@mongodb.com', 'username': 'dgottlieb'}Message: |
| Comment by Githook User [ 30/Mar/20 ] |
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Author: {'name': 'Daniel Gottlieb', 'email': 'daniel.gottlieb@mongodb.com', 'username': 'dgottlieb'}Message: |
| Comment by Githook User [ 25/Mar/20 ] |
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Author: {'email': 'daniel.gottlieb@mongodb.com', 'name': 'Daniel Gottlieb', 'username': 'dgottlieb'}Message: |
| Comment by Githook User [ 24/Mar/20 ] |
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Author: {'email': 'daniel.gottlieb@mongodb.com', 'name': 'Daniel Gottlieb', 'username': 'dgottlieb'}Message: |
| Comment by Alexander Gorrod [ 22/Mar/20 ] |
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Thanks for the excellent write-up daniel.gottlieb - that matches the plan is a much clearer explanation than I've been able to muster. |
| Comment by Susan LoVerso [ 20/Mar/20 ] |
daniel.gottlieb thank you for this clear and concise statement, it speaks the language I understand and helps me a lot in the reviews I'm doing. |
| Comment by Daniel Gottlieb (Inactive) [ 20/Mar/20 ] |
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To make sure I got this right, I'll state my interpretation/understanding (which I'm extending to include 4.0 so I understand the bigger picture):
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| Comment by Alexander Gorrod [ 20/Mar/20 ] |
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milkie and daniel.gottlieb would you mind taking a look at this? It's blocking some upgrade downgrade work, so I'd appreciate it if we could get it addressed quickly. |