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Date: Tue, 19 Mar 2013 18:14:45 +0100
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] [RFC PATCH RDMA support v4: 03/10] more verbose
 documentation of the RDMA transport
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To: "Michael R. Hines" <mrhines@linux.vnet.ibm.com>
Cc: aliguori@us.ibm.com, "Michael S. Tsirkin" <mst@redhat.com>, qemu-devel@nongnu.org, owasserm@redhat.com, abali@us.ibm.com, mrhines@us.ibm.com, gokul@us.ibm.com

Il 19/03/2013 18:09, Michael R. Hines ha scritto:
> Allowing QEMU to swap due to a cgroup limit during migration is a viable
> overcommit option?
> 
> I'm trying to keep an open mind, but that would kill the migration
> time.....

Would it swap?  Doesn't the kernel back all zero pages with a single
copy-on-write page?  If that still accounts towards cgroup limits, it
would be a bug.

Old kernels do not have a shared zero hugepage, and that includes some
distro kernels.  Perhaps that's the problem.

Paolo