Re: Recent kernel "mount" slow

From: Jeff Chua
Date: Thu Nov 22 2012 - 18:02:58 EST


On Wed, Nov 21, 2012 at 11:46 PM, Jeff Chua <jeff.chua.linux@xxxxxxxxx> wrote:
> On Wed, Nov 21, 2012 at 2:09 AM, Jan Kara <jack@xxxxxxx> wrote:
>> I haven't heard about such problem so far. What filesystem are you using?
>
> I've tried ext2/ext3/ext4/reiserfs/btrfs ... all seems to be slower
> than before. Seems to be fs independent.
>
>> Can you quantify 'is slower'? Bisecting would be welcome of course.
>
> Haven't measure, but it seems to be 1 sec instead of .3 sec to mount.
> I'll start bisecting:(
> So, since I've 6 mounts on start up, now it takes 4 seconds longer to boot up.

I started bisecting, and it seems to have multiple points of slowing
down. The latest kernel is really slow mounting /dev/sda1 (fs
independent) ... 0.529sec. Kernel 3.6.0 took 0.012sec, Kernel
3.7.0-rc2 took 0.168sec. Again, these are very early results. I'm
verifying them again.


Jeff
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