Question about VMM MMIO

Postings relating to old VirtualBox pre-releases
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Technologov
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Question about VMM MMIO

Post by Technologov »

Changelog says:
VMM: emulate even more MMIO and shadow pagetable exits without going back to user mode

In which cases it should improve performance?
Does this belongs to VT-x with EPT? Without EPT? AMD-V?
Does this also affect software virtualization?

Thanks in advance,
-Technologov
michaln
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Re: Question about VMM MMIO

Post by michaln »

Technologov wrote:Changelog says:
VMM: emulate even more MMIO and shadow pagetable exits without going back to user mode

In which cases it should improve performance?
In cases that previously forced a R0->R3->R0 roundtrip.
Does this belongs to VT-x with EPT? Without EPT? AMD-V?
All of those.
Does this also affect software virtualization?
Possibly, but probably not much.
Technologov
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Joined: 10. May 2007, 16:59
Location: Israel

Re: Question about VMM MMIO

Post by Technologov »

Okay, thanks
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