[LU-255] use ext4 features by default for newly formatted filesystems

• Type: Improvement
• Resolution: Fixed
• Priority: Major
• Fix Version/s: Lustre 2.1.0
• Affects Version/s: Lustre 2.1.0
• Assignee: Andreas Dilger
• Reporter: Andreas Dilger

Description

There are a number of ext4 features that we should be enabling by default for newly-formatted ldiskfs filesystems. In particular, the flex_bg option is important for reducing e2fsck time as well as avoiding "slow first write" issues that have hit a number of customers with fuller OSTs. Using flex_bg would avoid 10-minute delay at mount time or for each e2fsck run. As well, it would be useful to also enable other features like huge_file (files > 2TB) and dir_nlink (> 65000 subdirectories) by default.

All of these features are enabled by default if we format the filesystem with the option "-t ext4". Alternately, we could enable these individually in enable_default_backfs_features().

See http://events.linuxfoundation.org/slides/2010/linuxcon_japan/linuxcon_jp2010_fujita.pdf for a summary of improvements. While we won't see the 12h e2fsck -> 5 minute e2fsck improvement shown there (we already use extents and uninit_bg), the flex_bg feature is definitely still a win.

Comments

[Andreas Dilger]

Patch is landed for 2.1.0, closing bug.

[Build Master (Inactive)]

Integrated in lustre-master » i686,server,el6,inkernel #122
LU-255: enable ext4 features by default

Oleg Drokin : eb012d4a10208b26c2d3e795a90f1bb07dde6d91
Files :

• lustre/utils/mkfs_lustre.c
• lustre/lvfs/fsfilt_ext3.c

[Build Master (Inactive)]

Integrated in lustre-master » x86_64,server,el6,inkernel #122
LU-255: enable ext4 features by default

Oleg Drokin : eb012d4a10208b26c2d3e795a90f1bb07dde6d91
Files :

• lustre/lvfs/fsfilt_ext3.c
• lustre/utils/mkfs_lustre.c

[Build Master (Inactive)]

Integrated in lustre-master » x86_64,server,el5,ofa #122
LU-255: enable ext4 features by default

Oleg Drokin : eb012d4a10208b26c2d3e795a90f1bb07dde6d91
Files :

• lustre/lvfs/fsfilt_ext3.c
• lustre/utils/mkfs_lustre.c

[Build Master (Inactive)]

Integrated in lustre-master » i686,server,el5,ofa #122
LU-255: enable ext4 features by default

Oleg Drokin : eb012d4a10208b26c2d3e795a90f1bb07dde6d91
Files :

• lustre/lvfs/fsfilt_ext3.c
• lustre/utils/mkfs_lustre.c

[Build Master (Inactive)]

Integrated in lustre-master » i686,server,el5,inkernel #122
LU-255: enable ext4 features by default

Oleg Drokin : eb012d4a10208b26c2d3e795a90f1bb07dde6d91
Files :

• lustre/lvfs/fsfilt_ext3.c
• lustre/utils/mkfs_lustre.c

[Build Master (Inactive)]

Integrated in lustre-master » x86_64,client,ubuntu1004,ofa #122
LU-255: enable ext4 features by default

Oleg Drokin : eb012d4a10208b26c2d3e795a90f1bb07dde6d91
Files :

• lustre/utils/mkfs_lustre.c
• lustre/lvfs/fsfilt_ext3.c

[Build Master (Inactive)]

Integrated in lustre-master » i686,client,el6,inkernel #122
LU-255: enable ext4 features by default

Oleg Drokin : eb012d4a10208b26c2d3e795a90f1bb07dde6d91
Files :

• lustre/lvfs/fsfilt_ext3.c
• lustre/utils/mkfs_lustre.c

[Build Master (Inactive)]

Integrated in lustre-master » x86_64,server,el5,inkernel #122
LU-255: enable ext4 features by default

Oleg Drokin : eb012d4a10208b26c2d3e795a90f1bb07dde6d91
Files :

• lustre/lvfs/fsfilt_ext3.c
• lustre/utils/mkfs_lustre.c

[Build Master (Inactive)]

Integrated in lustre-master » x86_64,client,el5,ofa #122
LU-255: enable ext4 features by default

Oleg Drokin : eb012d4a10208b26c2d3e795a90f1bb07dde6d91
Files :

• lustre/utils/mkfs_lustre.c
• lustre/lvfs/fsfilt_ext3.c