1 Jun
2004
1 Jun
'04
5:24 a.m.
On Tue, 2004-06-01 at 08:14, Malcolm Baldridge wrote:
> So, am I completely hosed with my Adaptec SCSI
drive setup? Anybody
> have any insight into these Adaptec controllers? I've fussed with the
> setpci latency_timer settings (from Jan Depner's "Installing and
> configuring ALSA, JACK, & Ardour..." web site), but still see long
> xruns.
If you could email the output from lspci -v and
procinfo, that would be great.
Also, which exact kernel setup are you using? Preemptible?
Preempt+low-latency? Con Kolivas' "LCK1" patches which combine O(1)
scheduler, and two sets of low-latency patches, including patches to the I/O
subsystem?
Also, which filesystems are you using for your audio data drive? If you're
using ext3, which journalling mode? data=writeback seems to provide alot
better latency than the default data=ordered. Reiserfs seems to solve alot
of problems as well, if you're willing to reformat your audio drive. It's
easier to change your ext3 journalling mode (no reformat is necessary).
What kind of SCSI drives are you using?
I had these problems as well. There's a long thread a few months back
where it was confirmed that I tried *everything*. Eventually I gave up
and bought an IDE drive. Hey presto, problems gone. Now the only xruns
happen when there's scsi disk activity, according to vmstat.
The only time I didn't have these problems was with a MSI dual-athlon
board that had a 64-bit PCI slot where the 29160 was plugged in. I only
realised later (after the motherboard was on a ship to Taiwan, for a
different reason) that the 64-bit slot was on a separate bus from the
32-bit slot where the audio card (Terratec EWS88MT) was plugged in. That
board didn't give me xruns either. I think that's a plausible
explanation, but then again it may have been because there were 2 cpus.
On the other hand, I can't help wondering if the bus-greediness of the
Adaptec controllers isn't a driver issue. I had a brief look at the
driver sources, but I don't know enough about kernels and drivers to
have made sense of them.
bye
John