On 8/12/2010 2:09 AM, Supra Uche wrote:
I want to learn how a cpu type change effects my application performance. When a new generation mainframe is produced, it comes with hundreds of new instructions. I think that new instructions run applications more efficiently than the previous ones. Also for example if i had a 1000 MIPS capacity 1 CPU old machine, the new generation mainframe comes with 1200 MIPS capacity per CPU. If I think like, "the number of mips increased also the instructions will be more efficient than the previous ones. So my total gain is bigger than the mips capacity increase", is that idea correct or not ? Or is that directly related with the operating system version? If i dont upgrade my z/OS, will i able to get the benefit of new instructions?
These days MIPS are a marketing tool, but are pretty meaningless in translating into performance. The actual throughput varies too much on the pipeline processing and your instruction mix. While new machines generally may be considered to improve instruction execution, not necessarily all instructions benefit. For example, the execute instruction appears to be relatively slower on some newer processors. The operating systems is fairly stable, and upgrading it does not necessarily provide any improvement (with some specific exceptions). Newer instructions are more likely to be used by non-OS components and user applications.
Gerhard Postpischil Bradford, VT ---------------------------------------------------------------------- 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
