Jeff> How many are more than "a few?" I don't know. What can you do today in commercial stuff, 16 processors? How many cores per die, two? Four? We're still talking < 100 processors with access to the same chunk of memory. For the OP's problem that's still 10,000 users per processor. Maybe that's small enough, but if not, he'll need multiple processes across machines that don't share memory.
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