[LU-8365] Fix mballoc stream allocator to better use free space at start of drive

• Type: Bug
• Resolution: Unresolved
• Priority: Major
• Affects Version/s: Lustre 2.8.0
• Labels: ldiskfs
• Severity: 3
• Assignee: Yang Sheng
• Reporter: Lokesh Nagappa Jaliminche (Inactive)

Description

Provide a mechanism to reset the ldiskfs extents allocation position to near the beginning of a drive

Issue Links

• is duplicated by: LU-2377 Provide a mechanism to reset the ldiskfs extents allocation position to near the beginning of a drive
• is related to: LU-12103 Improve block allocation for large partitions
• is related to: LU-12970 improve mballoc for huge filesystems
• is related to: LU-14438 backport ldiskfs mballoc patches

Comments

[Gerrit Updater]

Oleg Drokin ([e-mail]) merged in patch https://review.whamcloud.com/34842/
Subject: LU-8365 ldiskfs: procfs entries for mballoc
Project: fs/lustre-release
Branch: b2_12
Current Patch Set:
Commit: ea7103b0b1c360b0e6d7fe62e275df366bf4e31d

[Gerrit Updater]

Andreas Dilger ([e-mail]) uploaded a new patch: https://review.whamcloud.com/34842
Subject: LU-8365 ldiskfs: procfs entries for mballoc
Project: fs/lustre-release
Branch: b2_12
Current Patch Set: 1
Commit: 1afff0d0a40ddf3c413c1db5a21d8d46da61e1c2

[Gerrit Updater]

Oleg Drokin ([e-mail]) merged in patch https://review.whamcloud.com/21142/
Subject: LU-8365 ldiskfs: procfs entries for mballoc
Project: fs/lustre-release
Branch: master
Current Patch Set:
Commit: 75703118588f2b23afd8c8815e5ebb768fc7a8ff

[Andreas Dilger]

Ihara had started running some tests on the patch, but I don't recall ever seeing the results.

The main goal was to automate the original "manually reset to the start of the disk during benchmarking" behavior under normal usage. In particular, jump back to earlier groups when a bunch of free space becomes available, without having to continually scan the earlier groups for free space. The potential drawback is if this happens too frequently it could cause excessive seeking, but since it should only happen when there is a large amount of space any seek overhead should be smaller than the seek rate * IO size.

[Alexander Zarochentsev]

are there any performance tests for this patch https://review.whamcloud.com/33195 ?

[Gerrit Updater]

Yang Sheng ([e-mail]) uploaded a new patch: https://review.whamcloud.com/33548
Subject: LU-8365 ldiskfs: fix wrong logic of stream allocation
Project: fs/lustre-release
Branch: master
Current Patch Set: 1
Commit: 52116e1483cb24e3f5d0c2a3f20fa989dbd75e63

[Yang Sheng]

Hi, Andreas,

This is the patch has already landed to upstream. I just want to get some input from Alex whether it is correct for stream allocation. Since it changes logic of stream allocation.

Thanks,
YangSheng

[Andreas Dilger]

I'm not sure why you attached the patch here? That is what gerrit is for.

[Yang Sheng]

Hi, Alex,

Could you please give a advice for this patch? 0001-ext4-Fix-bugs-in-mballoc-s-stream-allocation-mode.patch

Thanks,
YangSheng

[Gerrit Updater]

Yang Sheng ([e-mail]) uploaded a new patch: https://review.whamcloud.com/33195
Subject: LU-8365 ldiskfs: try to alloc block toward lower sectors
Project: fs/lustre-release
Branch: master
Current Patch Set: 1
Commit: 7e6352641724a26685247a21be488e43401437eb