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From: Peter Maydell <peter.maydell@linaro.org>
Date: Wed, 27 Jun 2018 11:49:35 +0100
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Subject: Re: [Qemu-devel] Drop support for 32bit hosts in qemu? (was: [PULL
 1/6] audio/hda: create millisecond timers that handle IO)
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To: Gerd Hoffmann <kraxel@redhat.com>
Cc: BALATON Zoltan <balaton@eik.bme.hu>, Martin Schrodt <martin@schrodt.org>, Thomas Huth <thuth@redhat.com>, Max Reitz <mreitz@redhat.com>, Markus Armbruster <armbru@redhat.com>, QEMU Developers <qemu-devel@nongnu.org>

On 27 June 2018 at 09:52, Gerd Hoffmann <kraxel@redhat.com> wrote:
>   Hi,
>
>> > Is QEMU still useful on 32-bit hosts?  Honest question!
>>
>> I guess it depends on what 32-bit hosts you consider. If you look at only
>> x86 vs. x86_64 then probably x86 is not that important any more but for some
>> embedded systems/SoCs 32bit might still be common and QEMU useful for those
>> (also as host not only emulated).

I would generally agree with this. For x86 32-bit is probably
droppable, but for non-x86 the situation is much less clear.

> Well.  I've used kvm with an 32bit arm soc (cubietruck).  It's very
> slow.  And all the arm architecture improvements to support kvm better
> are for aarch64 only.

Cubietruck (a Cortex-A7) is a pretty slow 32-bit Arm core.

Ask again in a couple of years :-)

thanks
-- PMM