Find the way to improve the performance about pyxel HOT 6 CLOSED

Hello,

For a first try, the perf utility on Linux could be used to determine which function use the most resources. I'll give it a quick try to see precisely where the bottleneck is.

from pyxel.

How is your oscillator being a bottleneck?

It looks very similar to what I'm doing myself in my own software synthesizer (however, mine is using a generator to produce the soundwave values) see https://github.com/irmen/synthesizer/blob/master/synthplayer/synth.py#L899
I think your oscillator inner loop may suffer from the fact that you're calling a function to get every individual value.

Another thing, which is a problem with Python, is that your sound generator code from the stream callback will run in a separate thread but this will block other Python code from executing. The only easy way around this is to either move all of your sound generation code into a C extension module that can release the GIL, or use a separate process

I assume you need realtime sound synthesis because the program seems to be able to change the sound notes and parameters on the fly? If not you can also consider generating whole audio clips in advance and playing those, rather than generating every individual sample value on the fly

from pyxel.

@irmen
Regarding oscillator. Actually I didn't measure the performance of it, but on my MacBook, sometimes noise occurs and I think it may be caused by the under flow of the oscillator.

As you wrote, the reason generating sound in real time is to control it from applications flexibly. So if possible, I'd like to keep this style.

Your code is very helpful! So should I use generator to reduce function calling overhead?

from pyxel.

@marespiaut It would be great help! I expect that the measurement result will be come out.

from pyxel.

@kitao benchmark/measure your oscillator code first to know its limits now.

As an indication, my FastTriangle oscillator performs like this on my computer:

testing FastTriangle ... 1960 K iterations/sec (44.5 x realtime @ 44100 hz)

If you create a sounddevice with half the output hz (22050) the speed will be almost twice as high because only half of the audio data has to be generated. That may also be an easy fix.

from pyxel.

For now, there's no request for performance improvement. So I close this issue once.

from pyxel.