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RAM disk in AIX

RAM disk in AIX

AIX provides 'mkramdisk' command for producing a disk that resides in the RAM for very high I/O intensive applications like database.
Here is a simple set of commands to create a ramdisk and a filesystem on top of it:

  1. create a RAM disk specifying the size
        # mkramdisk 5G
The system will assign the available RAM disk.  Since this is the first one, it will be called as ramdisk0
  1. Check for the new disk
        # ls -l /dev | grep -i ram
If there isn't sufficient available memory, the mkramdisk command will warn about the same during the creation.

  1. Create and mount a filesystem on top of the ram disk
    # mkfs -V jfs2 -o log=INLINE /dev/ramdisk0
    # mkdir -p /ramdisk0
    # mount -V jfs2 -o log=INLINE /dev/ramdisk0 /ramdisk0

The new filesystem will now be available like any other FS.  

To remove a ram disk, unmount/remove the filesystem and use 'rmramdisk' command to remove the ram disk.

A more detailed description of the article can be found at IBM Magazine website
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