Right. You get V=R, but not the I/O assist benefits. So it is sort of like locking all pages into memory. So in most cases that doesn't help. If you can get benefit from MDC, then you probably aren't using many Dedicated disks (they are not eligible for MDC but required for I/O assist). As others have mentioned, it is likely that you cannot drive the processor to capacity because of waiting for I/O. The things one might want to look at is the ratio of CP CPU time to Virtual I/O rate. That will give you an idea if there are any additional CP costs for handling MDC vs a real I/O. In most cases, MDC is cheaper, but there are exceptions. You might also want to look in the user state sampling of your favorite performance monitor and see if you see a shift in the guest from waiting on I/O to waiting on CPU or Running.
Edward M. Martin <[EMAIL PROTECTED]> writes: >Hello Bill, > > I can see that the NOMAD2 users will drive the CPU to 100%. >With MDC on. Without MDC it seems to be 10-15% less. I am getting the >stats now.
