Eric said; > > I also qualified the use of MIPS in my original comment by saying that > comparisons within a line of computers, such as z/890 & z/990. > Comparing a 1 processor z/990 to a 30 processor z/990 should give > a good comparison if you are using MIPS. Obviously, your particular > workload may give somewhat different numbers, but then it probably > would with MSUs also.
This is really where the standard way of thinking about these things just falls apart. There are multiple levels of virtualization within these systems. It is meaningless to talk about the "capacity" of the entire processor (CEC) when the processor is just a container for one or more LPARS. Moreover, the mix of resources and workloads is both unpredictable and irreproducable. If you study the LSPR information (ignoring for a moment whether you believe it) you see a wide variety of throughput results depending on configuration and workload mix. It is completely hopeless to think of that in terms of a single number called "MIPS" even if that number gives you some comfort. > MIPS have been around a lot longer than MSUs. They are more > familiar to me, which is why I like them. I still remember my > 158 with an attached processor. The main CPU alone gave 1 MIP, > and with the AP, it was 1.8 MIPS. Back in 1980, that was a good > sized machine. And today it would be less than a rounding error. That's the point. The way that we as a community thought about these systems back then is just not relevant or valid any more. MSU numbers are at least a shot at adjusting the scale of reference, but ultimately there is no substitute for measuring your own throughput with your own mix. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
