I develop "vendor" code. Customers always ask about CPU time. If I answered "oh we don't worry about that anymore" do you think they would buy? Do you think I would have a job?
Charles Composed on a mobile: please excuse my brevity Ted MacNEIL <[email protected]> wrote: >On a 600 MIPS single engine (z/990 class) 1,000,000 instructions is 0.17% of a >CP. These days? > >- >-teD >- > Original Message >From: John McKown >Sent: Monday, February 17, 2014 13:15 >To: [email protected] >Reply To: IBM Mainframe Discussion List >Subject: Re: Branch (was: Performance question - adding) > >On Mon, Feb 17, 2014 at 12:03 PM, Paul Gilmartin <[email protected]>wrote: > >> On 2014-02-17, at 10:36, Ted MacNEIL wrote: >> >> > I have to ask: Why they big concern over a few instructions? >> > Optimisation of a few is not worth the >> effort these days. >> > >> Hmmm... No single instruction is worth optimizing. >> >> No single instruction among a million is worth optimizing. >> >> It's not worth optimising a million instructions because >> that would imply optimizing each, which is not worth it. >> >> E.E. asked whether the code is in a loop. >> >> -- gil >> >> >I guess that I ASSuMEd that the code was in a heavily used loop. If you >remove 1 instruction from a loop which is executed a million times, >assuming the instruction is "expensive", then it may well be worth the >effort. Or maybe even replacing it with two "simpler" instructions (such as >my thought on using IPM and SPM with an STOC instead of a JZ and ST). > > > >-- >Wasn't there something about a PASCAL programmer knowing the value of >everything and the Wirth of nothing? > >Maranatha! <>< >John McKown > >---------------------------------------------------------------------- >For IBM-MAIN subscribe / signoff / archive access instructions, >send email to [email protected] with the message: INFO IBM-MAIN > >---------------------------------------------------------------------- >For IBM-MAIN subscribe / signoff / archive access instructions, >send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
