Very nice! I put this quickly through the Firefox profiler, which looks like this: https://dl.dropboxusercontent.com/u/40949268/emcc/snesonline.png . Based on that, the two biggest CPU consumers are in processing audio (inside the game code), and reading or writing the SDL canvas buffer between the game code and the 2D canvas. This SDL canvas upload code is known to be very slow (_SDL_LockSurface and _SDL_UnlockSurface), and not very optimized. A custom non-SDL-esque path of uploading the framebuffer to a 2D canvas might speed up here considerably.
To profile the audio performance, try adding -g2 flag, and disable javascript.options.asmjs preference in about:config in Firefox for the duration of the profile. That should allow the profiler to show frames inside the audio update function as well. 2014-05-10 0:01 GMT+03:00 Christoph Husse <[email protected]>: > Well damn xD. Firefox is twice as fast :O. Game plays totally smooth > there with only 50% CPU utilization... > > Here can see for yourself if you like... Finally got it working I am > so happy lol: > > > https://dl.dropboxusercontent.com/u/27687180/WebServer/SNESOnline/SNESOnline.html > > Input is: > > Left, Right (steer), up, down (menu) > "A" for jump > "S" for use collectible > "D" for drive and advance menu > > I think anyone who is older than 20 years knows this game anyway :D > > Awesome job with emscripten. This is really impressive to myself. > Even though I have to say that the performance is still quite bad. On > my native C++ build it consumes about 30 times less CPU than in the > browser. > > > On Fri, May 9, 2014 at 10:13 PM, Christoph Husse > <[email protected]> wrote: > > Meh damn you are right... There was something wrong with firefox ;). > > Since the Web Audio API im using seems to be broken on Firefox, it > > doesn't utilize much CPU because it seems to be stalled by some audio > > stuff. Weird. I will have a look into it and keep you updated with the > > performance when audio is active :). > > > > On Fri, May 9, 2014 at 10:08 PM, Alon Zakai <[email protected]> wrote: > >> Ah, CPU emulator makes some sense if it has a bytecode VM or something > else > >> with packed data. > >> > >> That performance sounds very surprising. Is it on a fully optimized > build? > >> Do you see errors in the web console in firefox? It should warn if > there is > >> a perf problem like asm.js not validating. > >> > >> - Alon > >> > >> > >> > >> On Fri, May 9, 2014 at 1:06 PM, Christoph Husse > >> <[email protected]> wrote: > >>> > >>> Well I am porting a CPU emulator and it seems to think unaligned > >>> memory accesses are really cool, or well at least the programs that > >>> run on this emulator :) > >>> > >>> BTW, The port works now and runs almost good on Chrome... Like 100% > >>> CPU utilization (one core). I think I can queeze out a bit more by > >>> skipping some frames and using webworkers for some stuff too to get a > >>> smooth experience. > >>> > >>> But on Mozilla Firefox this port stinks. Like its a slideshow. Really > bad. > >>> > >>> On Fri, May 9, 2014 at 10:01 PM, Alon Zakai <[email protected]> > wrote: > >>> > That hasn't been my experience, actually - when I've ported apps, > they > >>> > tended to have just a small amount of unaligned accesses (e.g. in > >>> > network-reading code, serializing code, or GC code). Just rebuilding > >>> > after > >>> > fixing each one was fast enough. I'm surprised you have so many - > what > >>> > is > >>> > their cause? Does your app purposefully pack structs to unaligned > >>> > offsets or > >>> > something like that? Generally speaking it isn't "easy" to cause an > >>> > unaligned access in C/C++. > >>> > > >>> > - Alon > >>> > > >>> > > >>> > > >>> > On Thu, May 8, 2014 at 11:06 PM, Christoph Husse > >>> > <[email protected]> wrote: > >>> >> > >>> >> But back to the general public... I think its an awesome idea to add > >>> >> this > >>> >> option you described. Because an application with misaligned > accesses > >>> >> usually will not only contain one of them and it gets very tedious > to > >>> >> figure > >>> >> them all out if SAFE_HEAP terminates your app on every occasion. > Even > >>> >> further it might be possible to only report for each single line of > >>> >> SAFE_HEAP_LOAD etc ONCE per run, so that you don't get spammed with > >>> >> useless > >>> >> double reports. It's then easy to map the reported lines back to C++ > >>> >> sources > >>> >> with a debug info options as each SAFE_HEAP_LOAD will have the C++ > code > >>> >> line > >>> >> as a comment behind it (could be done in a simple script for > >>> >> instance)... > >>> >> > >>> >> As far as I know there is no tool outside of emscripten which allows > >>> >> you > >>> >> to enumerate unaligned accesses. Valgrind had a feature request but > it > >>> >> seems > >>> >> it landed on the GTFO TODO list for whatever reason... > >>> >> > >>> >> -- > >>> >> You received this message because you are subscribed to the Google > >>> >> Groups > >>> >> "emscripten-discuss" group. > >>> >> To unsubscribe from this group and stop receiving emails from it, > send > >>> >> an > >>> >> email to [email protected]. > >>> >> > >>> >> For more options, visit https://groups.google.com/d/optout. > >>> > > >>> > > >>> > -- > >>> > You received this message because you are subscribed to a topic in > the > >>> > Google Groups "emscripten-discuss" group. > >>> > To unsubscribe from this topic, visit > >>> > > >>> > > https://groups.google.com/d/topic/emscripten-discuss/tOz2Yc_sLuA/unsubscribe > . > >>> > To unsubscribe from this group and all its topics, send an email to > >>> > [email protected]. > >>> > For more options, visit https://groups.google.com/d/optout. > >>> > >>> -- > >>> You received this message because you are subscribed to the Google > Groups > >>> "emscripten-discuss" group. > >>> To unsubscribe from this group and stop receiving emails from it, send > an > >>> email to [email protected]. > >>> For more options, visit https://groups.google.com/d/optout. > >> > >> > >> -- > >> You received this message because you are subscribed to a topic in the > >> Google Groups "emscripten-discuss" group. > >> To unsubscribe from this topic, visit > >> > https://groups.google.com/d/topic/emscripten-discuss/tOz2Yc_sLuA/unsubscribe > . > >> To unsubscribe from this group and all its topics, send an email to > >> [email protected]. > >> For more options, visit https://groups.google.com/d/optout. > > -- > You received this message because you are subscribed to the Google Groups > "emscripten-discuss" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "emscripten-discuss" group. 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