The same way on HP Superdomes and we never had problems with that. I guess the only thing is that Oracle must be linked correctly in the beginning. For Linux, I think that should be using SMP kernel.
We're running 10.2.0.2 on AIX 5.3 with LPARs and my Unix admins threw in a few extra tenths of a CPU in our production environment without even giving me any advanced notice, which I wasn't too happy about considering we hadn't even tested it, but Oracle seemed to handle it without any problems and cpu_count magically went up from 8 to 10. Honestly, I'm not even sure how many tenths of physical CPUs I'm running on. All I know is what it looks like according to topas, vmstat, sar and Oracle, which are all in agreement that there were 8, and are now 10, virtual/logical CPUs, but I don't really know exactly how it's configured behind the scenes other than that there are really only 4 multi-core CPUs in the box. My Unix admins like to keep me in the dark as much as possible so I don't ask too many questions. You'll notice when you run the AIX 5.3 performance utilities there are metrics called ent and entc% or something like that - can't remember for sure off the top of my head, but these represent the number of virtual CPUs your LPAR is entitled to, and the % of your entitlement you are consuming.
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