OK, so you're using AIX, not everyone is familiar with it, so consider providing sample input to the Perl script

svmon
   -P, mem usage for the following PIDs
   -t$n, Displays memory usage statistics for the top $n processes
[download]

So that's our input. We skip the first line by insisting that $. (input line number) is 2
Then allow following lines with the OR $& (last pattern match, from line 2 on exists)
There is also a redundant check on !$s++ which only can return true when $s=0
however if the line consists of dashes "-" reset the counter to zero.

For more precise answers try adding the input, the result of svmon -Pt15 to the enquiry.
Hope this helps.
UPDATEBy the way this code is horribly inefficient and seems to be written for obscurity more than for effectiveness