Tmpfs not using swap [Solved]

Question

i have set up /tmp as tmpfs for compiling but i get errors when i run out of memory, i was under the assumption that when tmpfs runs out of memory it uses swap space but swap never gets used even when swappiness is set to 100
df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda1 19G 729M 18G 4% /
none 1.9G 1.8M 1.9G 1% /dev/shm
none 1.9G 864M 983M 47% /tmp
none 10M 332K 9.7M 4% /var/log
none 10M 44K 10M 1% /var/run
none 10M 0 10M 0% /var/lock
/dev/sda2 19G 1.6G 17G 9% /usr
/dev/sda3 185G 3.1G 172G 2% /home
mount
/dev/sda1 on / type ext4 (rw,noatime)
none on /dev type ramfs (rw,relatime)
none on /proc type proc (rw,relatime)
none on /sys type sysfs (rw,relatime)
none on /dev/pts type devpts (rw)
none on /dev/shm type tmpfs (rw)
none on /tmp type tmpfs (rw)
none on /var/log type tmpfs (rw,size=10m)
none on /var/run type tmpfs (rw,size=10m)
none on /var/lock type tmpfs (rw,size=10m)
/dev/sda2 on /usr type ext4 (rw,noatime)
/dev/sda3 on /home type ext4 (rw,noatime)
free
total used free shared buffers cached
Mem: 3780388 1494456 2285932 0 42884 1084512
-/+ buffers/cache: 367060 3413328
Swap: 8000360 0 8000360
Last edited by guzz46 (2009-08-23 23:51:48)

Answer 1

# /etc/fstab: static file system information
# <file system> <dir> <type> <options> <dump> <pass>
none /dev/pts devpts defaults 0 0
none /dev/shm tmpfs defaults 0 0
none /tmp tmpfs defaults 0 0
none /var/log tmpfs defaults,size=10m 0 0
none /var/run tmpfs defaults,size=10m 0 0
none /var/lock tmpfs defaults,size=10m 0 0
#/dev/cdrom /media/cd auto ro,user,noauto,unhide 0 0
#/dev/dvd /media/dvd auto ro,user,noauto,unhide 0 0
#/dev/fd0 /media/fl auto user,noauto 0 0
/dev/sda1 / ext4 defaults,noatime 0 1
/dev/sda2 /usr ext4 defaults,noatime 0 2
/dev/sda3 /home ext4 defaults,noatime 0 2
/dev/sda4 swap swap defaults 0 0
do you have to specify tmpfs instead of none under file system?
Edit: i also tried
# /etc/fstab: static file system information
# <file system> <dir> <type> <options> <dump> <pass>
none /dev/pts devpts defaults 0 0
tmpfs /dev/shm tmpfs defaults 0 0
tmpfs /tmp tmpfs defaults 0 0
tmpfs /var/log tmpfs defaults,size=10m 0 0
tmpfs /var/run tmpfs defaults,size=10m 0 0
tmpfs /var/lock tmpfs defaults,size=10m 0 0
#/dev/cdrom /media/cd auto ro,user,noauto,unhide 0 0
#/dev/dvd /media/dvd auto ro,user,noauto,unhide 0 0
#/dev/fd0 /media/fl auto user,noauto 0 0
/dev/sda1 / ext4 defaults,noatime 0 1
/dev/sda2 /usr ext4 defaults,noatime 0 2
/dev/sda3 /home ext4 defaults,noatime 0 2
/dev/sda4 swap swap defaults 0 0
mount
/dev/sda1 on / type ext4 (rw,noatime)
none on /dev type ramfs (rw,relatime)
none on /proc type proc (rw,relatime)
none on /sys type sysfs (rw,relatime)
none on /dev/pts type devpts (rw)
tmpfs on /dev/shm type tmpfs (rw)
tmpfs on /tmp type tmpfs (rw)
tmpfs on /var/log type tmpfs (rw,size=10m)
tmpfs on /var/run type tmpfs (rw,size=10m)
tmpfs on /var/lock type tmpfs (rw,size=10m)
/dev/sda2 on /usr type ext4 (rw,noatime)
/dev/sda3 on /home type ext4 (rw,noatime)
but nothings changed, i'm sure it's a tmpfs because /tmp reads 1.9gb and everythings in there is gone after a reboot but it still doesn't use swap as backup
Last edited by guzz46 (2009-08-23 12:38:43)