2009-03-03 23:07:20

by Jan Engelhardt

Subject: ext4: odd values for mkfs.ext4 -i

Hi,



Is it ok that e2fsprogs-1.41.4 allows odd values for -i, such as
in `mkfs.ext4 -i 2047`? If inodes were arranged every 2047 bytes, they
would not be aligned, which would mean one extra sector would have to be
read every now and then, does not it?
Should odd values be rejected?

[BTW: this mailing list address should be mentioned at
e2fsprogs.sf.net]


Jan

2009-03-04 00:11:32

by Andreas Dilger

Subject: Re: ext4: odd values for mkfs.ext4 -i

On Mar 04, 2009 00:07 +0100, Jan Engelhardt wrote:
> Is it ok that e2fsprogs-1.41.4 allows odd values for -i, such as
> in `mkfs.ext4 -i 2047`? If inodes were arranged every 2047 bytes, they
> would not be aligned, which would mean one extra sector would have to be
> read every now and then, does not it? Should odd values be rejected?

Note that the "-i" value is a ratio between the total space in the filesystem
and the number of inodes. It does not dictate how those inodes are layed
out on disk.

Cheers, Andreas
--
Andreas Dilger
Sr. Staff Engineer, Lustre Group
Sun Microsystems of Canada, Inc.