Re: esound eats CPU cycles

[deman win tue nl (Ronald de Man)]

> Ronald de Man writes:
>  > I have the lastest version from CVS. No sound is playing, just
>  > esd running in the background. Esd should be sleeping, and strace
>  > shows that it is. But the performance decrease is real.
> 
> Might you have slow DMA on your combination of motherboard and sound
> card?  Nearly all sound cards use DMA to transfer data, and I would be 
> very surprised if esd closed the sound device -- starting and stopping 
> the DMA often produces a click.  The device driver
> 
> Stop esd and try this:   dd if=/dev/zero of=/dev/dsp bs=8k count=20
> 
> I'll bet it clicks.  It does on mine.  While it's running, do your
> gzip test.  On my system it doesn't show any performance decrease.
> Does it on yours?

I'll try when I get home. This seems to be a very reasonable explanation.
My sound card is an SB16 without 16-bit DMA. I can play 16-bit sound
by setting the 16-bit channel equal to the 8-bit channel. I don't
know why this works but it does, and it is probably the reason of
the slow down. The computer shop where I bought the card is even
more crap than the card (Creative ViBRA 16X PnP).

Thanks for the explanation! I'll report later if this is the real
problem.

Ronald