Hi Doug, you should consider using ficon attached storage on the z800 for database workload. In addition, consider using LVM striping over multiple volumes or alternatively LVM multipath on parallel access volumes to get your IO thoughput up to a reasonable level. With regard to memory size, you do have some advantages when running on a Mainframe with z/VM. One is, that z/VM will be able to swap out servers that are currently idle and/or not driving loads of IO at the moment. The other one is, that your memory bandwidth and the cache sizes are much faster then on other platforms. The amount of memory overcommitment strongly depends on your workload, a factor of 10 can indeed be valid in rare scenarios. However, most scenarios do lead to very crappy performance when using a factor 10 overcommitment ratio. With regard to PU horsepower, you do indeed have less horsepower on a z800 IFL than on your previous system, but unlike on Intel IO does not eat up your PU because IO processors handle it and because of decent memory bandwidth your PU will spend less time on waiting for your memory to deliver data. Since database workload is not too computing intensive but does cause a lot of IO, CPU utilization may not become a problem afaics.
with kind regards Carsten Otte -- I saw screens of green, red messages too, then came blue, shubidu And i think to myself, what a wonderful world ---------------------------------------------------------------------- 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
