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From: Paolo Bonzini <pbonzini@redhat.com>
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Date: Tue, 15 Dec 2015 12:59:52 +0100
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Subject: Re: [Qemu-devel] guest kernel in the host RAM
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To: "Denis V. Lunev" <den@openvz.org>
Cc: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>, QEMU <qemu-devel@nongnu.org>



On 15/12/2015 12:27, Denis V. Lunev wrote:
> The idea is that we could boot with the uncompressed Linux
> kernel in the guest which serves 2 purposes:
> - faster boot time as per Intel opinion
> - memory savings
> 
> Uncompressed kernel image could be the same for several
> guests and thus memory pages for the kernel could be the
> same, which saves a bit of RAM :)
> 
> At the moment neither BIOS support this in full: nor SeaBIOS,
> nor OVMF, nor QBoot.
> 
> From our point of view QBoot is an ideal candidate for this.

QBoot is not meant for use in production; SeaBIOS actually is just as 
fast if you configure it right.

> Do you have any opinion for the topic?

I honestly don't like the idea.  Linux patches itself a lot, which 
makes the memory savings minimal (if they exist at all).  What is the
decompression time for a kernel that is compressed with LZO?

Paolo