I noticed the large amount of allocation going on when I was using mandelbrot to test my fixes to the visualizer last week -- I'll take a look. I wrote an allocation hotspot profiler tool that may end up as part of the visualizer in some form, so I can try running it on your code. <div> </div><div> <div class="gmail_quote">On Tue, Jul 24, 2012 at 6:12 PM, Sam Tobin-Hochstadt <<a href="mailto:samth@ccs.neu.edu" target="_blank">samth@ccs.neu.edu</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> I've been trying to use the new futures visualizer (which is great) to improve my parallel version of the mandelbrot benchmark (collects/tests/racket/shootout/mandelbrot-futures.rkt). My current code is attached. You can run it like this: $ racket mand.rkt 4000 8 # 8 is the number of futures to use. The visualizer shows that each future syncs thousands of times for allocation. However, I can't find the allocation in the loop at all (even in the decompiler output). Does anyone have any suggestions on what might be allocating here, or any strategies I can use for finding the allocation? -- sam th <a href="mailto:samth@ccs.neu.edu">samth@ccs.neu.edu</a> _________________________ Racket Developers list: <a href="http://lists.racket-lang.org/dev" target="_blank">http://lists.racket-lang.org/dev</a> </blockquote></div> </div>