View Full Version : multiple commits in mount

ian dobson
January 18th, 2011, 09:11 PM

After upgrading my frontend to a ssd I've noticed that the drive seems to be accessed more other than I'd expect. Looking in fstab I see:-

cat /etc/fstab
# /etc/fstab: static file system information.
# <file system> <mount point> <type> <options> <dump> <pass>
proc /proc proc defaults 0 0
# /dev/sda1
UUID=671953de-a48b-464e-ac26-1707715287bf / ext4 discard,noatime,nodiratime,errors=remount-ro,data=writeback,commit=30 0 0
/dev/scd0 /media/cdrom0 udf,iso9660 user,noauto,exec,utf8 0 0
/dev/sda2 /mytharchive ext4 noatime,nodiratime,errors=remount-ro,data=writeback,discard,commit=30 0 0

when I type mount from the command line I see:-
/dev/sda1 on / type ext4 (rw,noatime,nodiratime,discard,errors=remount-ro,data=writeback,commit=30,commit=0)
proc on /proc type proc (rw)
none on /sys type sysfs (rw,noexec,nosuid,nodev)
fusectl on /sys/fs/fuse/connections type fusectl (rw)
none on /sys/kernel/debug type debugfs (rw)
none on /sys/kernel/security type securityfs (rw)
none on /dev type devtmpfs (rw,mode=0755)
none on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=0620)
none on /dev/shm type tmpfs (rw,nosuid,nodev)
none on /var/run type tmpfs (rw,nosuid,mode=0755)
none on /var/lock type tmpfs (rw,noexec,nosuid,nodev)
/dev/sda2 on /mytharchive type ext4 (rw,noatime,nodiratime,errors=remount-ro,data=writeback,discard,commit=30,commit=0)

Why am I seeing commit=30,commit=0? and does the kernel/ext4 fs use 0seconds or 30 seconds for the write delay?

Ian Dobson

ian dobson
January 19th, 2011, 08:09 PM

OK, this looks like a bug in mountall when called from upstart/init scripts.

If I just all mountall after the system has booted the the commit=0 vanishes :confused:

Ian Dobson