Android - add script to mount /cache as tmpfs

adb shell
su

Show list of mounted partitions:

cat /proc/mounts

Found there to what block /system mounted and remount as writable

mount -o rw,remount -t yaffs2 /dev/block/mtdblock5 /system

Then create init script e.g. /etc/init.d/05cache2tmpfs with following contents:

umount /cache
mount -t tmpfs -o size=42M,nr_inodes=42k,mode=0770 tmpfs /cache
chown system.cache /cache