Swap
Just like on some other UNIX systems, IRIX can use swap. This article explains how to enable swapfiles for more swap.
General Procedure
# mkfile -v 2048m /usr/swap
/usr/swap 2147483648 bytes
# swap -a /usr/swap
This will enable the file immediately. To ensure it works next boot add the following line to /etc/fstab:
/usr/swap swap swap pri=3 0 0