dsimcha wrote:
I'm working on optimizing some code now, and a nagging issue that I've been meaning to bring up is how slow stuff runs when profiling is turned on. It seems that, given any code that's slow enough to be worth profiling/optimizing, the DMD profiler slows it down further, to the point where it's impractical to profile because it would take forever to get the results. Does anyone have any tips for speeding this up?
You could try using an external non-intrusive profiler. If you compile your stuff with GCC on *nix, I've been hearing that kcachegrind is pretty awesome: http://kcachegrind.sourceforge.net/html/Home.html If you'd like to profile a DMD-Win-compiled executable, I've written a simple tool to do it which is similar to the Sleepy profiler: http://sleepy.sourceforge.net/ ( Sleepy doesn't work with DMD-made executables ): http://team0xf.com:1024/dprof/ ; if you compile Main.d and run it, passing the name of your executable as a parameter, it will attach to it (your app must be compiled with -g and without -O). Then it pauses the target thread a few thousand times a second, checking its register states and finding the currently executed function. The stats are gathered and when you hit Enter, you're provided with some info. The program is a pretty simple one and may not do what you'd like, however the actual profiler is a separate lib (dprof.Profiler) which could be used in a more sophisticated way. So far, I've used it to successfully optimize some ray-tracing code and remove a few bottlenecks from Hybrid.
-- Tomasz Stachowiak http://h3.team0xf.com/ h3/h3r3tic on #D freenode
