Aha, a thread convergence! I started the "Ardour..." thread lamenting long xruns under the 2.6 kernels. Based on recommendations on the list, I went back to a 2.4 kernel, still having the occasional long xrun. In the "XRuns..." thread, the following from a post by Jan Depner caught my eye: "What kind of disk drives? Adaptec SCSI controllers can give you problems with xruns." Uh-oh. I'm using an Adaptec controller on my main board (a 7890). With a little digging, I came up with the following from the ST Audio website (http://www.staudio.de/kb/english/conflicts/): "The famous Adaptec 2940 SCSI controller series is causing performance problems when installed in the same system as our DSP24 series and when the audiodata is stored on a SCSI-HDD connected to the controller. To get good results in benchmark tests, the Adaptec controller keeps steady access to the PCI bus. The result is a reduction of data transfer of other PCI cards like the DSP24 hardware. This means that the ASIO/MME buffer size (which is the latency) needs to be set to a relative high value to avoid stuttered audio playback and drop-outs during recording. The performance problems can be reduced if both the DSP24 and the Adaptec controller both have a unique and unshared IRQ. Still the performance will not be as good compared to the regular onboard IDE-controller of a modern mainboard. This means that the best solution is to use a IDE-HDD to save the audiodata from within your recording software. The simple presence of the controller (that is used while the audiodata is stored on a IDE-HDD) is no problem." Uh-oh again. The 7890 is the on-board version of the 2940. I thought I had the xruns pretty much under control with the 2.4 kernel, then I picked up a M-Audio Delta 1010LT (I was jonesing for the 8 channels of input!). Ugh. I can't record more than a few seconds of 8 channel input before a 100msec+ xruns brings everything to a halt. Even recording 2 channels won't make it through a 4:00 min song. 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. Trying an IDE drive is not that simple, as I don't have any drive slots left in the box (I've got 4 SCSI drives setup as a RAID). So, I'd like to exhaust all possibilities before trying new drive configurations. Any thoughts/ideas/suggestions would be _greatly_ appreciated! Thanks, Joel
