Hi folks:
I wanted to find out if there is any performance benefit to using the SCSI disk type for a WinXP Guest versus the default IDE setting. I have a few WinXP guests using the default IDE drive, and it seems that whenever the IDE guest hard disk gets used the CPU usage as perceived by the guest goes to 100% even though no excess usage is shown for the guest process on the host o/s (win 2003 server). Also, it looks like processes that are using the CPU on the guest are "pushed aside" while this is going on, as I note that CPU usage for the guest process as viewed by the host o/s actually drops significantly while the guest is doing IDE disk I/O. It almost looks as if the guest O/S is unable to schedule I/Os to the virtual IDE disk and do other work while waiting for the I/Os to complete, and instead the guest CPU is put is some sort of pseudo kernel loop while the I/Os are outstanding in order to make sure that no other multitasking can occur.
I wanted to find out if this is a disadvantage of using the IDE device type for the main guest drive under WinXP. I understand that I'll have to get the SCSI drivers into the boot process for a WinXP guest if I want to switch, just as I would on a real system, so I wanted to find out of the performance was enough better to be worth going to the trouble. I know that for Linux distributions WMWare recommends using a SCSI drive, and I have a SMEServer guest o/s running fine in that configuration.
Feedback welcome.
mudtoe