[LU-11012] lfs settripe does not clear pool in PFL

• Status: Resolved
• Project: Lustre
• Fix Version/s: Lustre 2.12.0
• Type: Bug
• Priority: Minor
• Reporter: CEA
• Assignee: Peter Jones
• Resolution: Fixed
• Severity: 3

Description

on following conf : 3 OST 2 POOLS (POOL1=OST0 POOL2=OST1 OST3)

lfs setstripe -E 4M -p POOL1 -E 8M -p POOL2 -E EOF -c 3 pfl1

1. lfs getstripe pfl1
   pfl1
   lcm_layout_gen: 3
   lcm_mirror_count: 1
   lcm_entry_count: 3
   lcme_id: 1
   lcme_mirror_id: 0
   lcme_flags: init
   lcme_extent.e_start: 0
   lcme_extent.e_end: 4194304
   lmm_stripe_count: 1
   lmm_stripe_size: 1048576
   lmm_pattern: raid0
   lmm_layout_gen: 0
   lmm_stripe_offset: 0
   lmm_pool: POOL1
   lmm_objects:

• 0: { l_ost_idx: 0, l_fid: [0x100000000:0x1e:0x0] }

lcme_id: 2
lcme_mirror_id: 0
lcme_flags: 0
lcme_extent.e_start: 4194304
lcme_extent.e_end: 8388608
lmm_stripe_count: 1
lmm_stripe_size: 1048576
lmm_pattern: raid0
lmm_layout_gen: 0
lmm_stripe_offset: -1
lmm_pool: POOL2

lcme_id: 3
lcme_mirror_id: 0
lcme_flags: 0
lcme_extent.e_start: 8388608
lcme_extent.e_end: EOF
lmm_stripe_count: 2      -> wrong should be 3 (but logic because of pool choice)
lmm_stripe_size: 1048576
lmm_pattern: raid0
lmm_layout_gen: 0
lmm_stripe_offset: -1
lmm_pool: POOL2               <- wrong, no POOL was specified in layout component

 

Comments

[Andreas Dilger]

Hi JC,
This is working as expected. The PFL file components will inherit parameters (stripe_count, stripe_size, pool) from the previous component (or the filesystem-wide defaults for the first component) if they are not specified. This avoids the need to specify the same parameter for each component repeatedly.

To specify that no pool should be used in your example, you can use -pool="" for the last component. In Lustre 2.11, it is also possible to use "-pool=none" to specify no pool.

[jacques-charles lafoucriere]

Hi Andreas,

This is a good news. May be I have read the manual too quickly (pdf and man) but I did not find this inherit concept.

If absence in manuals is confirmed, we should add it clearly in the manuals

[Gerrit Updater]

Andreas Dilger ([e-mail]) uploaded a new patch: https://review.whamcloud.com/32463
Subject: LU-11012 doc: describe layout inheritance in lfs-setstripe.1
Project: fs/lustre-release
Branch: master
Current Patch Set: 1
Commit: db543efd37eaa462c6445a22402b085234323351

[Gerrit Updater]

Oleg Drokin ([e-mail]) merged in patch https://review.whamcloud.com/32463/
Subject: LU-11012 doc: improve the lfs-setstripe.1 man page
Project: fs/lustre-release
Branch: master
Current Patch Set:
Commit: cd4489a34cfd640a99d6a1ceb65303fddd34a7ae

[Peter Jones]

Landed for 2.12