[gentoo-user] makewhatis -u

[KH]

Hi,

during an update I read somewhere something like: "Hey run makewhatis -u 
. Also you should have a cronjob doing this regularly."
I never heard of this before (but I am not the real geek - more like a 
user) but I wonder how regularly I should have the cronjob run the 
command. Is this to be done with every update or like every hour (like I 
do with locate -u)?
Thanks for suggestions