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Let's say I have four VM's open, each running an identical version of Windows. Under my current setup, the guest OS will be loaded into memory four times. Much of that is wasted space.

Using any VM host on the market, is there any way to consolidate that memory usage?

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up vote 1 down vote accepted

Some VMware products already do this. At least, I'm 95% certain that Server and ESXi already do this. I'm not as sure about Player, Workstation, or Fusion, but I'd be surprised if they didn't.

I don't know if other hosts do this or not.

Edit: I believe that Xen and KVM also do page sharing.

What host software are you using?

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Now that I have a name ("page sharing"), it's a lot easier to search for. I'm using VMware Workstation 5.5. According to it should be working, but it's not. From what I've read, apparently it kicks in slowly over time... maybe I'm not being patient enough, but I wish there was a way to force a memory consolidation at any time. Oh well, thanks for the info. – zildjohn01 Apr 30 '10 at 15:10

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