> Also, I think there is a misunderstanding about the performance > counters: they (the ones I ment) are CPU architecture specific and > neither gcc nor gprof knows about them. They are implemented as "extra"
fwiw: I never have seen anything like that published (or even mentioned). Things like the number of clock cycles to execute a specific sequence of instructions have never been published afaik. The RPP ratings of a model are determined by running well-defined instruction mix benchmarks (and these probably are aimed more towards running z/OS than Linux). Most likely processor design was done to favor common instruction sequences (e.g. an XC instruction with memory operands may not really fetch the operand if both addresses are the same). I would not be surprised if such low level instrumentation were only present in the hardware simulators they use for processor design. The particular model number is not shown by Q CPUID. The processor type for all S/390 (9672 in your case) and Freeway machines (2064) is the same. Changes in clock speed, cache size, look aside tables, extra instruction sets etc tend to mark 'generations' (like G5 vs G6). And since you run in a virtual machine you probably care about CP overhead. A virtual machine runs at native speed under control of SIE until it touches any of the architecture items marked for interception (at that point the control program will further complete the virtualisation or deal with the intercept otherwise). The smaller the number of SIE intercepts, the closer the virtual machine gets to native speed. Rob
