very long log recovery at mount

[Arkadiusz Miśkiewicz]

Hi.

I got such situation, fresh boot, 4.1.10 kernel, init scripts start mounting 
filesystems. One fs wasn't very lucky:

[   15.979538] XFS (md3): Mounting V4 Filesystem
[   16.256316] XFS (md3): Ending clean mount
[   28.343346] XFS (md4): Mounting V4 Filesystem
[   28.629918] XFS (md4): Ending clean mount
[   28.662125] XFS (md5): Mounting V4 Filesystem
[   28.980142] XFS (md5): Ending clean mount
[   29.049421] XFS (md6): Mounting V4 Filesystem
[   29.447725] XFS (md6): Starting recovery (logdev: internal)
[ 4517.327332] XFS (md6): Ending recovery (logdev: internal)

It took over 1h to mount md6 filesystem.

Questions:
- is it possible to log how much data is needed to be recovered from log? Some 
data that would give a hint on how big this is (and thus rough estimate on how 
long it will take). Not sure if that's known at time when this message is 
being printed.

XFS (md6): Starting recovery (logdev: internal, to recover: xyzMB (?))

- now such long mount time is almost insane, so I wonder why could be the 
reason. Is the process multithreaded, single threaded? cpus were idle

-- 
Arkadiusz Miśkiewicz, arekm / ( maven.pl | pld-linux.org )