Leak detection used to be easier.

It's become complicated by the fact that OS's and programs will put off disposing of free'd blocks until "they feel like" it. Java is particularly troublesome about this. I've had to toss 100s of objects out of scope before I see their finalize methods finally start getting called.

You may want to try more interations. I've found that programs have to run awhile before their memory consumption levels off. There are artifacts in support libraries that keep their own private stashes of memory and don't start giving that up(if ever) until they've been used for a while.

I haven't used Purify for a while, are you certain that it managed to instrument the perl library as it was going along?