Re: [patch 0/6] Guest page hinting version 7.

From: Rik van Riel
Date: Thu Apr 02 2009 - 15:09:58 EST


Martin Schwidefsky wrote:
The benefits are the same but the algorithmic complexity is reduced.
The patch to the memory management has complexity in itself but from a
1000 feet standpoint guest page hinting is simpler, no?
Page hinting has a complex, but well understood, mechanism
and simple policy.

Ballooning has a simpler mechanism, but relies on an
as-of-yet undiscovered policy.

Having experienced a zillion VM corner cases over the
last decade and a bit, I think I prefer a complex mechanism
over complex (or worse, unknown!) policy any day.
Ok, I can understand that. We probably need a KVM based version to show
that benefits exist on non-s390 hardware as well.
I believe it can work for KVM just fine, if we keep the host state
and the guest state in separate places (so the guest can always
write the guest state without a hypercall).
--
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/