I find this problem very strange as when one uses 96khz/24bit for his sessions, it takes 96000 x 3 = ~300Kbytes per second and track. That would mean as little as 2,4Mbytes/sec when you record eight tracks simultaneously, which is less than 1/5 of what hdparm shows your disk is capable of… Even if you use ~20 tracks or so, your system should be able to handle that, if the disk has no other use than the DAW job, am I right? So I have been asking myself: why the heck is my system telling me it is unable to keep up with ardour when I use as little as eight mono tracks and two or three plugins?
I set up a performance monitor in my tray which showed 100% processor load every time I started playback or recording. Later on, I discovered that there was a plugin /either a delay or an eq, not quite sure right now/ which caused my system to overload - even when playback has been stopped! Everything would just freeze, my mouse would take 20 seconds to show any response to having been moved and nothing would make my system work again, save, surprisingly, playback: when I pressed the spacebar in such situation, Ardour started playing and even if the system load has been horrible, the system at least responded. I would then hit Alt+F2, wait for a while and then type killall ardour and Enter. And the processor load monitor would go down like a stone in the water in as little as two seconds! Ardour would go down then, too, of course, which is the only drawback of the above method :oP so probably my disk is as little autonomous as a disk can be, as it must have posed a lot of processor interrupts to cause such an overload. /Not mentioning that plugin as I haven’t been using it anymore./
I have been using Reaper on W2K later on and I ran into virtually the same problem: with around 12-15 tracks /and yes, around the same number of plugins plus some master compressor etc./ the processor would load up to hundred percent and yes, the system would slow down significantly, but the playback would continue, which I find essential. The number of tracks and plugins in use seems twice as large as with Ardour, but the samplerate has been set to 44100Hz, so I wouldn’t say there was any significant change to the amount of data processed. The same machine, just to make it clear; using Ext2, Ext3 and Reiser filesystem for all my linux work and storage and NTFS under M$, of course. No dualboot, though: I replaced Debian with the W2K platform, partly to try and fiddle with Reaper a bit and partly for there is still as little good ladspa plugins on the road and as many free VSTs which I already know from when I used to use Cubase and which do not work on Linux yet /I never figured out how to get the Wine/FST thing to work for me, yes, I am lame ;oP/
So. The issue remains the same. There is a problem between the disks and Ardour; no matter where it lays, it is sure to become a headliner once users run into the need of trying the unlimitedness of Ardour’s track count. Other systems such as the above mentioned W2K/Reaper combination of course do have the same problem. That and my experiences with other platforms I came across (ie Gentoo/Ardour 2, MacOS X/ProTools, WXP/Cubase SX3,…) persuaded me that the problem is not software dependent and that DAW work /unless you process one mono vocal recording for, say, rewriting it on a sheet of paper/ is god damn hardware intensive and no matter what OS/DAW do you use and how much do you pay for it, the main brake of your system will be always the hardware. Sad.