[LU-5916] OST pool inheritence is no longer persistent (no LOV EA for child directory)

• Type: Bug
• Resolution: Fixed
• Priority: Critical
• Fix Version/s: Lustre 2.7.0, Lustre 2.5.4
• Affects Version/s: Lustre 2.6.0, Lustre 2.7.0, Lustre 2.5.2, Lustre 2.4.3
• Labels: HB
• Environment: el6; Lustre 2.4 to Lustre 2.7 (master).
• Severity: 3
• Assignee: Niu Yawei (Inactive)
• Reporter: Thomas LEIBOVICI - CEA (Inactive)

Description

A child directory should inherit from the OST pool of its parent.

In Lustre 2.4 to master (2.7), this is no longer the case: the child directory has no LOV EA stored on the MDS, so the pool inheritance is lost when the MDS restarts.

lfs getstripe indicates the child directory doesn't inherit from its parent pool.

mkdir /mnt/lustre/dir
lfs setstripe -p lustre.pool1 /mnt/lustre/dir
lfs getstripe -p /mnt/lustre/dir
returns "lustre.pool1" (correct)
mkdir /mnt/lustre/dir/subdir
lfs getstripe -p /mnt/lustre/dir/subdir
-> empty (should return lustre.pool1)
getfattr -n trusted.lov -d /mnt/lustre/dir/subdir
/mnt/lustre/dir/subdir: trusted.lov: No such attribute
touch /mnt/lustre/dir/subdir/file
lfs getstripe -p /mnt/lustre/dir/subdir/file
returns "lustre.pool1" (correct). Its seams the MDS inherited the pool somehow.

Then, after restarting the MDS:
touch /mnt/lustre/dir/subdir/file2
lfs getstripe -p /mnt/lustre/dir/subdir/file2
-> empty (should be lustre.pool1)

Comments

[Gerrit Updater]

Oleg Drokin ([e-mail]) merged in patch http://review.whamcloud.com/13411/
Subject: LU-5916 lod: inherit default pool setting properly
Project: fs/lustre-release
Branch: b2_5
Current Patch Set:
Commit: 56211bf18fbca9930d77cea1ee0e3f2d83d59ec4

[Niu Yawei (Inactive)]

port to b2_5: http://review.whamcloud.com/#/c/13411/

[Gerrit Updater]

Niu Yawei ([e-mail]) uploaded a new patch: http://review.whamcloud.com/13411
Subject: LU-5916 lod: inherit default pool setting properly
Project: fs/lustre-release
Branch: b2_5
Current Patch Set: 1
Commit: 840c3fa79c535578b17037ae9f3f6a4838255531

[Niu Yawei (Inactive)]

Sure, I'm going to port it to b2_5.

[Henri Doreau (Inactive)]

Could a backport to b2_5 be considered? The patch fixes a critical regression.

[Jodi Levi (Inactive)]

Patch landed to Master.

[Gerrit Updater]

Oleg Drokin ([e-mail]) merged in patch http://review.whamcloud.com/12746/
Subject: LU-5916 lod: inherit default pool setting properly
Project: fs/lustre-release
Branch: master
Current Patch Set:
Commit: e8214d6bd4ccc3ff386c77904664c60f1848ef11

[Gerrit Updater]

Niu Yawei ([e-mail]) uploaded a new patch: http://review.whamcloud.com/12746
Subject: LU-5916 lod: inherit default pool setting properly
Project: fs/lustre-release
Branch: master
Current Patch Set: 2
Commit: 4c11c85c283bb200cadc492be42b298aefea1177

[Niu Yawei (Inactive)]

I looked into the code closer and realized that the NAME_LOV for default stripping/pool is declared in lod_declare_object_create() and the NAME_LOV is set in mdd_object_create() -> lod_xattr_set() -> lod_dir_striping_create(), but for the case of parent has only pool setting (no default stripping), inheriting NAME_LOV is skipped mistakenly, see lod_dir_striping_create_internal():

        /* Transfer default LOV striping from the parent */
        if (lo->ldo_striping_cached &&
            !LOVEA_DELETE_VALUES(lo->ldo_def_stripe_size,
                                 lo->ldo_def_stripenr,
                                 lo->ldo_def_stripe_offset)){

This patch fix the problem: http://review.whamcloud.com/#/c/12746

[Gerrit Updater]

Niu Yawei ([e-mail]) uploaded a new patch: http://review.whamcloud.com/12746
Subject: LU-5916 lod: inherit default pool setting properly
Project: fs/lustre-release
Branch: master
Current Patch Set: 1
Commit: 2b237b11932af2b8dcf4a0401fc8e6c7cee37fbf