Changing shared memory size in Linux

Currently the size is showing as 738M:

# df -h /dev/shm
Filesystem      Size  Used Avail Use% Mounted on
tmpfs           738M     0  738M   0% /dev/shm

Add the following entry into /etc/fstab:

tmpfs /dev/shm tmpfs defaults,size=1G,nodev,nosuid 0 0

Now remount:

# mount -o remount /dev/shm

We can now see that the size has been changed:

# df -h /dev/shm
Filesystem      Size  Used Avail Use% Mounted on
tmpfs           1.0G     0  1.0G   0% /dev/shm