Performance problem with my script ...suggestions pls

Hi ,
I have included my script below, pls read thro this req. I want my script to run for every hour , the problem is I CANNOT USE CRONTAB which is prohibited inside the company. My script does what it is supposed to do (to determine the memory and then send a email if it crosses a certain limit) . So I put a while loop which is always true so that the script can run forever using nohup but the problem is that this script if run using nohup and while true condition seem to REALLY take up almost 1 full cpu from the server (our server is a 3 cpu box) ..do u guys have any idea how to make this less CPU intensive one..??
_____ Script ----
#!/bin/ksh
set -A proc $x
x=$(top| grep sieb |awk '{print $6}'|sed 's/\M//')
print $x
HOME=/users/home/con
TEMPDIR=$HOME
FILE=mail.log
set -A proc $x
print "Number of sieb process currently running is ${#proc[@]}"
#assigning the total number of processes to a var
procnum=${#proc[@]}
print ${proc[1]}
#to make the script run contineous im putting a while [true]
while [ true ]
do
#intializing a counter var to be in loop
i=0
while [ $i -lt $procnum ]
do
echo 'Start checking '
if [ ${proc[i]} -gt 1420 ]
then
echo Process Sieb seem to occupy more memory about ${proc[i]} MB so will sleep for 10mins before i do next check
sleep 600
typically 62% means the overall emory is 83%
cp=$(prstat -t 1 1 | awk '/sad/{print $5;}'|sed 's/\%//')
echo $cp is the % MEM
if [ ${proc[i]} -gt 1420 ] && [ $cp -gt 61 ]
then
echo Sieb seem to occupy more memory so will send a email
/usr/bin/mailx -s "ALERT: process memory on rog is high " "con@yahoo.com" < $TEMPDIR/$FILE
sleep 3600
fi
fi
print ${#proc[$i]}
((i=i+1))
echo $i
done
done

quick answer - use the "sleep" command to make your process go dormant for a set amount of time.

do a man sleep - but basically, the command is sleep <seconds>

My first thought was using sleep, too, but he is.

sleep 600

So, maybe that long of a sleep is giving the CPU fits? when I had this problem before, and wasn't using a sleep command, I solved it using sleep 1 which gave the CPU plenty of time to catch up on other things.

I can't imagine a company setting a policy against using one of the most powerful friends a sysadmin has. Amazing what people do.... But, I've an open mind. Convince me that prohibiting the use of cron is a good idea.