clear tmpfs in my case

Question

I am on a Ubuntu machine.

I have make a directory under root directory, by:

$ sudo mkdir /hello
$ sudo mkdir /hello/bye

Then I mount tmpfs with size 1024M to /hello/bye by:

$ sudo echo "tmpfs   /hello/bye   tmpfs   size=1024M,mode=0777  0  0" >> /etc/fstab
$ sudo mount -a

In future , How to clear /hello/bye (tmpfs) ?

Answer 1

If by clear you mean delete all files in there, it's like any other directory:

rm -rf /hello/bye/*

If you mean unmount the tmpfs partition simply do:

umount /hello/bye

Having put the line

tmpfs   /hello/bye   tmpfs   size=1024M,mode=0777  0  0

in your /etc/fstab, that partition will be automatically mounted at every boot. If you don't want to automout use the noauto option:

tmpfs   /hello/bye   tmpfs   size=1024M,mode=0777,noauto  0  0

If you don't need the partition any more, simply delete that line from /etc/fstab and delete the directory /hello/bye.

Answer 2

If its like mounting a clean partition everytime the machine reboots with no content in it. I would suggest to use ramfs. It will be faster since its in physical memory, can treat it as any other mounted accessible filesystem but would go away every time the machine reboots.

# mkfs -q /dev/ram1 8192
# mkdir -p /ramcache
# mount /dev/ram1 /ramcache
# df -H | grep ramcache