Why could Shark be so slow?

Question

I'm trying to profile Ruby interpreter. I run shark -i ./ruby bm_sudoku.rb or something like that, the script finishes in less than a second, and then Shark goes to "CHUDData - Analyzing samples... 99.3%.." point and stays there frozen for 10 minutes or so. It finishes eventually, it's just so ridiculously slow it's pretty much unusable.

Version I have here is OSX 10.5, shark 4.6.1 (227).

Any ideas what that might be?

Answer 1

There's some sort of strange problem in 10.5 with Shark being glacially slow loading symbols which can take several minutes. I don't see the problem in 10.6, and that seems to mirror the same behaviour seen by Chromium developers.

Answer 2

Try Instruments -- the CPU sampler is similar to shark and it is a lot faster. No pause at the end.