Ram disk creation on Linux

Ramdisks are very useful in the case of web servers for some heavily accessing contents.

The steps for crating Ramdisk is as follows,
Step 1: 

Edit the file /boot/grub/grub.cfg and add the entry "ramdisk_size={size in  KB}". For example if you need to crate 4GB of RAM disk, the entry should look like,


 ### BEGIN /etc/grub.d/10_linux ###
menuentry 'Ubuntu, with Linux 2.6.32-21-server' --class ubuntu --class gnu-linux --class gnu --class os {
    recordfail
    insmod ext2
    set root='(hd0,1)'
    search --no-floppy --fs-uuid --set ab3827ac-8003-4bed-81c0-9248d64362b0
    linux    /vmlinuz-2.6.32-21-server root=UUID=bbfccfa9-f878-4c42-83c1-0d82c3b2f44b ro quiet  ramdisk_size=4194304
    initrd    /initrd.img-2.6.32-21-server

Make sure the above entry made is in end of the linux kernel entry and it should be in a single line.

Once you done this, do a reboot and make the kernel read the parameter while next boot.

Step 2:

You can create the ramdisk using the following command,

      mkfs -q /dev/ram1 {size of ramdisk to me created in KB}

Create a folder to act as the mount point for above created ramdisk.

      mkdir -p /ramcache 

Mount the ramdisk to /ramcache

      mount /dev/ram1 /ramcache 

Following command will display the mounted partitions including the ramdisk.

      df -H