[linux-audio-dev] TiMidity as a CPU hog

[Jens M Andreasen]

Hi Dave, Takashi!

I've got timidity up and running now, as a server under OSS. Made me
self a new option to read directly from /dev/sequencer2 (The
documentation says the input format should be similar to /dev/sequencer,
but that's wrong.)

The first note I play actually happens, and resembles an acoustic piano
with a bit of wobbly reverb. So far so good ...

The problem is that it stops rendering as soon as I release the note and
then only renders when there is new midi-input (as in massaging the
modulation wheel like a mad man ...). I have tried turning active
sensing ON on my keyboard to no avail.

Then I started to look further into the sources in search for the actual
synthesizer. There is some 3MB of cross-platform C-code and headers, and
most of it is not what I'm looking for.

So far I have only localized the soundfont loader and I am currently
reading up on the struct that defines the format. If I can find (or if
you can help me find?) the parts that actually assigns and renders a
note, then I should be able to write a new CPU-friendly voice-assigner

The goal would be to pruduce something like a tmdt--. That is to say: 
Timidity++ unbloated, a module which only includes the stuff needed to
run as a softsynth under Linux.

So, where is the damned synthesizer? :)


mvh // Jens M Andreasen


On tor, 2004-06-10 at 21:47, Dave Phillips wrote:
> Greetings:
> 
>   Can someone explain why TiMidity eventually hogs the CPU at 95% or 
> more after running for a while (like  12 hours or more) ? I'm talking 
> about hogging the chip while TiMidity is idling, not playing. I'm using 
> it as a softsynth, it works well, but even in the latest version its CPU 
> usage just soars. Here's how I'm invoking 2.13.0 :
> 
>     timidity -iA -B2,8 -c /home/dlphilp/timidity.cfg -A100 -Oj 
> -EFreverb=0 -EFchorus=0
> 
>   Takashi: Obviously I spoke too soon in my earlier message. I just 
> looked at top again and saw that TiMidity was eating up 96% of the CPU. :(
> 
> Best,
> 
> dp
> 
> 
>