8 Apr
2007
8 Apr
'07
2:51 p.m.
On Sun, Apr 08, 2007 at 01:38:34PM +0200, Karl Hammar wrote:
Andrew Burgess <aab(a)cichlid.com>om>:
I am slightly confused. Is it necessary to increase the latency
timer for a pci sound card? This seems slightly
counter-intuitive. Wouldn't this reduce the performance of the
sound system through that card?
The only thing the above script changes on my system is the
latency of the SB Live.
James
Paul Davis wrote:
>> What could cause clicks without xruns? I'm baffled.
>PCI bus hogging, for one thing. consider running a script like this
...
Here one that works automatically for all
multimedia devices:
# find multimedia devices
pcis=$(lspci -v | grep Multimedia | awk '{ print $1; }')
if test -z "$pcis"; then
echo WARNING: no multimedia devices found on pci bus
else
for p in $pcis; do
echo set maximum latency timer for $p
setpci -s $p latency_timer=ff
done
fi
It does not work for me:
$ lspci | grep Multi | head -1 | cut -b-75
0000:00:05.0 Multimedia audio controller: nVidia Corporation nForce MultiMe
$ setpci -s 0000:00:05.0 latency_timer
lspci: -s: Invalid slot number
$ setpci -s 00:05.0 latency_timer
00
I have to remove the first 0000: from lspci, as in:
$ cat /usr/local/sbin/pci.set.audio
#!/bin/sh
val=${1:-ff}
# find multimedia devices
pcis=$( lspci -n | grep ' 0401: ' | cut -f1 -d\ | cut -f2- -d: )
if test -z "$pcis"; then
echo WARNING: no multimedia devices found on pci bus
else
for p in $pcis; do
lspci -s $p
echo -en \\tmaximum latency timer:\
setpci -s $p latency_timer | tr -s ' \n' ' '
setpci -s $p latency_timer=$val > /dev/null
echo -n '-> '
setpci -s $p latency_timer
done
fi
$