XFS - Failling to remount

I recently converted to XFS on my Laptop.
I have laptop mode enabled, but found it was causing my laptop hang on shutdown.

After spending ages debugging the laptop mode scripts (over 1500 lines of code :|) I found the offending line of code was one that remounts the filesystem, now this remount was totally useless to me, as it uses the same mount options I already used, so I simply commented it out.

But I am still wondering why remount seems simply hangs (I left it for 3 minutes and no response, but the process cleanly terminate with a ctrl-c from bash) and it happens on both my XFS partitions and did not happen when I was running EXT3.

 

Hello,

If you want to analyze, you may want to try using strace. It's usually the first step in the system debugging.

Code:

strace -f -tT -o strace.out /path-to-command

-f will check all children (forks), -tT will give you time between system calls and inside system calls (in microseconds), so you can use this to see where the hang occurs.

Do it twice, once with xfs, once with ext3 and see what happens.

Run strace as root.

Reading the output may not be easy, but you can begin with diff and looking for very long times in and between system calls.

Cheers.
Mrk