In a recent note, Ted MacNEIL said: > Date: Fri, 22 Sep 2006 20:47:16 +0000 > > >ITYM that it's your *opinion* that TSO and production should be kept > >separate, but what do you mean by that? > > No! It's not my opinion. > It's from an old document from IBM, and I tend to agree with it. > It's not for security reasons; RACF/ACF2/TOPSECRET can handle that. > > It's for performance reasons. > You either have poor TSO response, or you have it impacting production. > > Neither is a good thing! > > >Separate LPAR? > > Good enough. > Without doubting that IBM said that, I'm trying to understand the reason. Compare:
Case A: o One LPAR with 100 TSO users o One LPAR with 50 production jobs (Adjust numbers to reality.) versus: Case B: o Two LPARs, each with 50 TSO users and 25 production jobs. OK. You're claiming Case A is the better design. But why? I had always believed the heterogeneous mix is better because jobs of each genus can exploit resources little used by the other(s). I understand, of course, that PR/SM can shift many resources among partitions according to demand; the partitions are porous. What are the exceptions? Main memory? WLM profiles? Other (specify)? Of course TSO jobs should have dispatching profiles different from batch -- shorter CPU time slices for TSO, etc. But couldn't that be done by assigning different profiles to the TSO jobs, even within the same LPAR. Perhaps it's the design of WLM that doesn't account for profoundly diverse behaviors within a single LPAR. Any explanation is welcome. -- gil -- StorageTek INFORMATION made POWERFUL ---------------------------------------------------------------------- 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
