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Some ado about zero

Posted Jul 9, 2009 10:56 UTC (Thu) by johill (subscriber, #25196)
In reply to: Some ado about zero by neilbrown
Parent article: Some ado about zero

Well imagine having 4096 zero pages. I guess you could better get away with just a percpu refcounter. But then again, why do you need to refcount the zero page anyway? It's always there to start with, and never writable, isn't it?

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Some ado about zero

Posted Jul 9, 2009 12:35 UTC (Thu) by Cyberax (✭ supporter ✭, #52523) [Link]

That's just 16MB. That's close to 'nothing' for a computer with 4096 CPUs.

Some ado about zero

Posted Jul 9, 2009 14:51 UTC (Thu) by ejr (subscriber, #51652) [Link]

There are single chips with dozens of CPUs from the OS's view. Soon these will be in the hundreds. And they'll end up being used in smaller devices relatively soon, simply because of economies of scale. The extra space can add up pretty quickly.