Subject: Re: [linux-audio-dev] Re: Sync Issues (was Re: External MIDI Sync using OSS/Free)
From: Benno Senoner (sbenno_AT_gardena.net)
Date: pe loka 29 1999 - 19:40:07 EDT
On Fri, 29 Oct 1999, Roger Larsson wrote:
>>
> Or you can try to find out what part of your video card driver that
> destroys latency and correct that.
>
> You can find out the problematic spot with my patch:
> latency-profiling-2.2.10-r6.patch [for Linux 2.2.10]
>>
> The results are messages in 'dmesg', latency time and instruction
> pointers
> are printed. You then decode the instruction pointers to routine name.
>
> /RogerL
Not quite correct: actually it's not a driver's fault !
In most cases the audio dropout while doing heavy GFX is caused by PCI busmaster
transfers by the gfx card that hogs the entire PCI bus for SEVERAL milliseconds,
in order to provide better gfx throughput.
On some cards you can avoid this problem by setting a special variable into
your XF86Config (no sample handy at the moment) , which slows down the gfx
performance a bit but gives you better lowlatency performance.
On some other cards the only solution is to throw your gfx card out of the
nearest window.
:-)
PS: Benjamin, I stopped the crossposting , at least for this mail.
:-)
Benno.
This archive was generated by hypermail 2b28 : pe maalis 10 2000 - 07:28:00 EST