Haven't tried it but I suspect more a kernel problem than a "tweak the last bits ot the controler" solution....
Did you try setting unmask irq on on those drives? (-u1 param w/ hdparm)
That doesn't improve at all.Also u could try setting the nice value of vmware higher so other apps get higher priority (nice -n 16 vmware) and see if that improves the situation.
Of course, but I think that the problem is more in the kernel than in the hardware.Ofcource IDE is just slow with multi access tasks.. Thats why scsi is still the standard with servers, its designed to be used for multi-app / multi access envirioments. While IDE might have caught up in raw read/write speed, it does not an server architecture make ;-) IDE controllers still lock in these situations, even if different channels are used.
I found a solution to this problem: Run a fresh compiled kernel with Interactivity patches.
The results are outstanding.... Fast, responsive even with high IOs.
With RH9 kernel, when MsDev (under win2k in vmware) was in link phase, making a lot of IOs, Mozilla (under native Linux) took between 3-10 seconds just to refresh a page....
With my compiled kernels, it counts in milliseconds! The background link is not even noticeable!
I even made a dd if=/dev/zero of=/tmp/file at the same time as the link, not noticeable!!!!
This marvel is a 2.4.20 kernel with the patch at http://members.optusnet.com.au/ckolivas/kernel/ck6_2.4.20.patch.bz2 applied.
-jec
