δΊ 2013-6-13 4:10, Paolo Bonzini ει:
Il 12/06/2013 10:11, Benjamin Herrenschmidt ha scritto:
On Wed, 2013-06-12 at 10:00 -0400, Paolo Bonzini wrote:
The only bug we have is not a performance bug related to compression;
it's that writing zero pages breaks overcommit. Let's fix that, and
only that.
Right, do we have a way to madvise "throw away" these instead ?
We already do that, but apparently that madvise is asynchronous.
Or do we
have a way to track that the platform init code did write something
there and only clear *those* pages ?
No need for; since it's copy-on-write, not copy-on-read :) we can just
check for pages that are zero and not rewrite them with zeros. That's
I think it is the right way to improve overcommit without breaking
anything.
what Peter's patches do, I'll review them right away.
Paolo
--
Best Regards
Wenchao Xia