Finding Installed Memory on Solaris 10

Even after 20 minutes of google searches I couldn't find a command to give the amount of installed memory on a Solaris machine. So I'm posting the solution here for safe keeping. Generally you need to be root to get the answer instead of an error message.

Use the command:

 /usr/sbin/prtdiag | head 

It should give output that looks like this:

# /usr/sbin/prtdiag | head
System Configuration: Sun Microsystems  sun4u Sun Fire V240
System clock frequency: 167 MHZ
Memory size: 2GB