Found out some big information. I wrote two test scripts, one polls the routing table of 1000 ip's, single threaded. The other polls the 1000 ip's as 100 threads. It does nothing except get the routing table -- it's the same polling code. The threaded version blows up on memory, the single threaded stays steady. So something about threads really hornkles Net::SNMP's nose. I contacted the author and he seems willing to look into it.

But man, atleast now I know *where* the leak is coming from. O_O