On Fri, 7 Aug 2009, Marcy Cortes wrote: > I'm getting conflicting answers from IBM. > > How does VM scale with regards to multiprocessors? In the z/OS world > the 1st z/10 engine is like 900 something MIPS and the 60th on the box > is something like 359. Does z/VM hosting Linux suffer the same fate? > (z/OS per engine pricing actually goes down to compensate for this, > z/VM's does not). > > > Marcy >
I think that is must because, to the best of my poor grasp of things, this is an effect of the __hardware__, not the software. I.e. interference between the CPUs for the memory bus and inter-CPU bus snooping and communications. E.g. when a CPU updates a location in memory, every other CPU must be sure to update or flush their cache if it includes this location in it. This slows down the CPUs. That is why it is good for work to not share memory, if possible. -- Trying to write with a pencil that is dull is pointless. Maranatha! John McKown
