From the NannyMUD documentation

LAST CHANGE

2000-12-18

COMMAND

NAME
        uptime - show the uptime of the game


SYNTAX
	uptime

DESCRIPTION
	This command will show you the last reboot time, as well as how long
	ago that was in days, hours, minutes and seconds, as well as a figure
	telling you how many bytes memory per second the game has used so far.


NOTE
	It does not take local summer time into account (unless efun::time()
	does).


NOTE
	The memory/time rate is almost without meaning. The game uses much
	memory in short time when it starts, but less thereafter.