Messages in this thread | | | Date | Mon, 12 Nov 2012 21:10:32 -0200 | From | Marcelo Tosatti <> | Subject | Re: [PATCH] KVM: MMU: lazily drop large spte |
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On Mon, Nov 05, 2012 at 05:59:26PM +0800, Xiao Guangrong wrote: > Do not drop large spte until it can be insteaded by small pages so that > the guest can happliy read memory through it > > The idea is from Avi: > | As I mentioned before, write-protecting a large spte is a good idea, > | since it moves some work from protect-time to fault-time, so it reduces > | jitter. This removes the need for the return value. > > Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> > --- > arch/x86/kvm/mmu.c | 34 +++++++++------------------------- > 1 files changed, 9 insertions(+), 25 deletions(-)
Its likely that other 4k pages are mapped read-write in the 2mb range covered by a read-only 2mb map. Therefore its not entirely useful to map read-only.
Can you measure an improvement with this change?
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