Re: [PATCH 0/2] ksm: take dirty bit as reference to avoid volatilepages

[Izik Eidus]

On 03/28/2011 04:14 PM, Nai Xia wrote:
> Currently, ksm uses page checksum to detect volatile pages. Izik Eidus
> suggested that we could use pte dirty bit to optimize. This patch series
> adds this new logic.

Hi,

One small note:
When kvm will use ksm on intel cpu with extended page tables support, 
the cpu won`t track
dirty bit, therefore the calc_hash() logic should be used in such cases
(untill intel will fadd this support in their cpus)...

Moreover I think that even though that AMD nested page tables does 
update dirty bit, you still need
to sync it with the host page table using mmu notifiers ?

(Not that on regular application use case of ksm any of this should be 
an issue)

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/