> On Tue, 23 Apr 2002 05:32:03 +0800, John Summerfield > <[EMAIL PROTECTED]> wrote: > > >> > ... > >> >This is nothing really new. Sharing a VM system with early releases of > >> >MVS was unpleasant. > >> > >> I hear that it's no problem with the two in different LPARs, and that > >> running MVS as a guest under VM works well with a surprisingly small > >> performance hit (in the 2-3% ballpark.) > >> -- > >> --henry schaffer > >> > > > >In the times when "Sharing a VM system with early releases of MVS was > >unpleasant," IBM hadn't invented LPARs and I think Gene had just released (o > r > >was about to release) the S/470s. > > > > > >MVS+VM, I was told, made the 168 comparable in performance to a 135. > > One of my first projects at Amdahl was supporting a product called > VM/PE, a boringly named, technically cool piece of software which > shared the real (UP) system between VM and MVS. S/370 achitecture is > dependent on page zero and this code swapped page zeros between MVS > and VM. It worked just fine for dedicated channels, nice low 1-2% > overhead. When we started sharing control units and devices, things > turned ugly. > >
I do believe we used VM/PE, before MDF became available. We used to run two, occasionally three MVS systems on a 5860. - -- Cheers John Summerfield Microsoft's most solid OS: http://www.geocities.com/rcwoolley/ Note: mail delivered to me is deemed to be intended for me, for my disposition. ============================== If you don't like being told you're wrong, be right!
