From mboxrd@z Thu Jan  1 00:00:00 1970
From: Cole Robinson <crobinso@redhat.com>
Subject: Re: [PATCH] KVM: s390: remove delayed reallocation of page tables
 for KVM
Date: Thu, 23 Apr 2015 09:57:32 -0400
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Cc: KVM <kvm@vger.kernel.org>,
	Cornelia Huck <cornelia.huck@de.ibm.com>,
	Jens Freimann <jfrei@linux.vnet.ibm.com>,
	Martin Schwidefsky <schwidefsky@de.ibm.com>
To: Paolo Bonzini <pbonzini@redhat.com>,
	Christian Borntraeger <borntraeger@de.ibm.com>,
	Alexander Graf <agraf@suse.de>
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On 04/23/2015 08:07 AM, Paolo Bonzini wrote:
> 
> 
> On 23/04/2015 13:43, Christian Borntraeger wrote:
>>>>
>>>> Couldn't you make this a hidden kconfig option that gets automatically selected when kvm is enabled? Or is there a non-kvm case that needs it too?
>> For things like RHEV the default could certainly be "enabled", but for normal
>> distros like SLES/RHEL, the idea was to NOT enable that by default, as the non-KVM
>> case is more common and might suffer from the additional memory consumption of
>> the page tables. (big databases come to mind)
>>
>> We could think about having rpms like kvm to provide a sysctl file that sets it if we
>> want to minimize the impact. Other ideas?
> 
> I can say what _won't_ work which is tying it to the KVM module.
> Nowadays it is loaded automatically via udev on the first /dev/kvm
> access, and that's already too late because qemu-kvm's page tables have
> been created already.  Right?
> 
> With my Fedora hat on, adding a sysctl file to the userspace RPMs (e.g.
> qemu) would work.  CCing Cole Robinson who is the main maintainer of the
> Fedora virt packages.
> 

>>From a packaging POV that sounds fine to me

- Cole