[LU-14985] Change stride/stripe-width on an existing ldiskfs filesystem Created: 04/Sep/21 Updated: 05/Sep/21 |
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| Status: | Open |
| Project: | Lustre |
| Component/s: | None |
| Affects Version/s: | Lustre 2.12.7 |
| Fix Version/s: | None |
| Type: | Bug | Priority: | Minor |
| Reporter: | Joe Frith | Assignee: | WC Triage |
| Resolution: | Unresolved | Votes: | 0 |
| Labels: | None | ||
| Environment: |
RHEL7.9 |
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| Severity: | 3 |
| Rank (Obsolete): | 9223372036854775807 |
| Description |
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There seems no way to change stride/stripe-width on an existing live ldiskfs OST LUN. We used incorrect stride/stripe-width with mkfs.lustre initially and now are seeing poor write performance. Is there a supported way of changing stride/stripe-width values? |
| Comments |
| Comment by Joe Frith [ 04/Sep/21 ] |
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Is it safe to use tune2fs -E stride=x,stripe-width=x on a mounted OST with data on it to change stride and stripe-size for a ldiskfs type OST device? |
| Comment by Andreas Dilger [ 04/Sep/21 ] |
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It would be useful if you included the "dumpe2fs -h" output for the device. Yes, it is fine to change these on a running filesystem, they only affect new allocations. In the past they also used to affect inode and block bitmap location, but the flexbg feature overrides this. |
| Comment by Andreas Dilger [ 04/Sep/21 ] |
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That said, it is likely that the mmp feature will prevent tune2fs from running while the filesystem is mounted. |
| Comment by Joe Frith [ 05/Sep/21 ] |
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Here is the output of dumpe2fs. The RAID backend is (8+2) with 512K chunk size. I believe the correct values are "
[root@oss2 ~]# dumpe2fs -h /dev/mapper/lustredisk01-01 [root@oss2 ~]# |