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From: Valerio Aimale <valerio@aimale.com>
Message-ID: <562F98D1.8060506@aimale.com>
Date: Tue, 27 Oct 2015 09:31:29 -0600
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Subject: Re: [Qemu-devel] QEMU patch to allow VM introspection via libvmi
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To: Markus Armbruster <armbru@redhat.com>
Cc: lcapitulino@redhat.com, Eduardo Habkost <ehabkost@redhat.com>, qemu-devel@nongnu.org

On 10/27/15 9:18 AM, Valerio Aimale wrote:
>
>
> I did not try to mmap'ing to a file on a RAMdisk. Without physical 
> disk I/O, the VM might run faster.
>
>

I did try with the file on a ramdisk

$ sudo mount -o size=3G -t tmpfs none /ramdisk
$ /usr/local/bin/qemu-system-x86_64 -name Windows10 -S -machine 
pc-i440fx-2.4,accel=kvm,usb=off [...] -mem-prealloc -mem-path /ramdisk

with that, the speed of the VM is acceptable. It will not take your 
breath away, but it is reasonable.