> -----Original Message----- > From: IBM Mainframe Discussion List > [mailto:ibm-m...@bama.ua.edu] On Behalf Of Bob Shannon > Sent: Thursday, August 20, 2009 12:56 PM > To: IBM-MAIN@bama.ua.edu > Subject: Re: zAAP on zIIP > > >But the millicode in an IFL is different from that in a CP > is different >from that in an ICF (?) is different from that > in a zAAP(?) is different >from that in a zIIP (?). > > I was once told that one cannot IPL off an ICF (or maybe it > was an IFL) because NIP issues an instruction that is not > supported on the specialty engine. If that's true, then NIP > is a special case. > > zIIPs and zAAPs support the full range of instructions. The > decision to route to zIIP or zAAP is made by the dispatcher. > The dispatcher can't examine the work to see what > instructions will be run, and the pathlength to run through > the FLIH and re-dispatch the work on a CP would be too long. > Hence once work is dispatched on a zIIP/zAAP everything has to work. > > Bob Shannon > Rocket Software
But there must be some way for the dispatcher to somehow know that CPU#n is a zIIP or a zAAP as opposed to a general CP. Otherwise how would the dispatcher know not to dispatch general work onto that CPU? I would guess that there is something in the PCCA(?) that says "this is a zIIP" or "this is a zAAP". Which I guess would be determined via some instruction at NIP time? Just a wild guess on my part. Hum. If that is true along with what you said, then the easy way to dispatch general work onto a zIIP or zAAP would be to "zap" that flag so that the dispatcher would think the zIIP or zAAP was a general CP. -- John McKown Systems Engineer IV IT Administrative Services Group HealthMarkets(r) 9151 Boulevard 26 * N. Richland Hills * TX 76010 (817) 255-3225 phone * (817)-961-6183 cell john.mck...@healthmarkets.com * www.HealthMarkets.com Confidentiality Notice: This e-mail message may contain confidential or proprietary information. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message. HealthMarkets(r) is the brand name for products underwritten and issued by the insurance subsidiaries of HealthMarkets, Inc. -The Chesapeake Life Insurance Company(r), Mid-West National Life Insurance Company of TennesseeSM and The MEGA Life and Health Insurance Company.SM ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
