How do I deallocate a Linux RAMDISK, e.g. /dev/ram0?

Question

I've been playing with Linux RAMDISKs, as in the block device /dev/ram0. I understand that when I first start writing to one of these devices some RAM is allocated to it.

How do I free the memory used by, say, /dev/ram0? Put another way: how do I indicate to the Linux kernel that I'm done and it can reclaim whatever resources are held by /dev/ram0?

Answer 1

Unless you format the ramdisk something along the lines of

mke2fs -m 0 /dev/ram0

The ramdisks themselves don't actually occupy any memory space.

If you do format and mount a ramdisk however, the only way that I remember doing is by using freeramdisk but that was a long long time ago.

Some other resources you might want to check out:

http://e2enetworks.com/2008/10/25/linux-in-memory-filesystems-tmpfs-vs-ramdisk/

http://www.vanemery.com/Linux/Ramdisk/ramdisk.html

http://www.linuxdoc.org/HOWTO/BootPrompt-HOWTO-3.html