[SERVER-15273] Only allocate powerOfTwo sized records in regular collections Created: 16/Sep/14 Updated: 02/Aug/18 Resolved: 18/Oct/14 |
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| Status: | Closed |
| Project: | Core Server |
| Component/s: | Storage |
| Affects Version/s: | None |
| Fix Version/s: | 2.7.8 |
| Type: | Task | Priority: | Major - P3 |
| Reporter: | Mathias Stearn | Assignee: | Mathias Stearn |
| Resolution: | Done | Votes: | 0 |
| Labels: | None | ||
| Remaining Estimate: | Not Specified | ||
| Time Spent: | Not Specified | ||
| Original Estimate: | Not Specified | ||
| Issue Links: |
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| Backwards Compatibility: | Minor Change | ||||||||||||||||
| Participants: | |||||||||||||||||
| Description |
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Going forward, MMAPv1 will only allocate powerOfTwo sized records, regardless of the flag. This is required to make the new freelist work correctly in O(1) time without any scanning. This only applies to regular collections. In particular it will not apply to capped collections or indexes. |
| Comments |
| Comment by Mathias Stearn [ 18/Oct/14 ] |
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Users that were explicitly turning off powerOf2 will need to switch to the stronger noPadding mode from |
| Comment by Githook User [ 18/Oct/14 ] |
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Author: {u'username': u'RedBeard0531', u'name': u'Mathias Stearn', u'email': u'mathias@10gen.com'}Message: Prep for new freelist implementation. |
| Comment by Mathias Stearn [ 17/Sep/14 ] |
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The usePowerOfTwo flags will be silently ignored, and we will just use powerOfTwo allocation in all cases. |