On Wed, Jul 04, 2012 at 07:40:05AM +0700, Fajar A. Nugraha wrote: > Are there any known btrfs regression in 3.4? I'm using 3.4.0-3-generic > from a ppa, but a normal mount - umount cycle seems MUCH longer > compared to how it was on 3.2, and iostat shows the disk is > read-IOPS-bound Is it just mount/umount without any other activity? Is the fs fragmented (or aged), almost full, has lots of files? > > # time mount LABEL=WD-root > > real 0m10.400s > user 0m0.000s > sys 0m0.060s > > # time umount /media/WD-root/ > > real 0m22.419s > user 0m0.000s > sys 0m0.064s > > # /proc/10142/stack <--- the PID of umount process The process(es) actually doing the work are the btrfs workers, usual sucspects are btrfs-cache (free space cache) or btrfs-ino (inode cache) that are writing the cache states back to disk. I'm using iotop to observe such things. david -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
