I can not add much to what Pieter already explained. When you expect these virtual machines to be active at the same time, you should have at least 3-4 GB in z/VM. If you don't have that, then you need to make the virtual machines smaller (and give more VDISK in return). If z/VM has that much memory, then you may indeed suffer from contention under the bar. For a short experiment you could see whether things improve when you enable MDC in main memory, and disable it in expanded storage (if you have that).
One additional thing to look at is block paging. If you are short on page space then VM can not find optimal free slots and your paging will be inefficient. It would be good to look at the actual page rates as well. Also notice there is a link to the 2nd disk - you don't have other data mixed with the page allocation, have you? Rob -- Rob van der Heij rvdheij @ gmail.com ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390
