"Michael S. Tsirkin" <mst(a)redhat.com> writes:
On Tue, Feb 28, 2023 at 09:40:49AM +0000, Daniel P. Berrangé wrote:
> On Tue, Feb 28, 2023 at 10:14:52AM +0100, Thomas Huth wrote:
> > On 28/02/2023 10.03, Michael S. Tsirkin wrote:
> > > On Tue, Feb 28, 2023 at 08:59:52AM +0000, Daniel P. Berrangé wrote:
> > > > On Tue, Feb 28, 2023 at 03:19:20AM -0500, Michael S. Tsirkin wrote:
> > > > > On Tue, Feb 28, 2023 at 08:49:09AM +0100, Thomas Huth wrote:
> > > > > > On 27/02/2023 21.12, Michael S. Tsirkin wrote:
> > > > > > > On Mon, Feb 27, 2023 at 11:50:07AM +0000, Daniel P.
Berrangé wrote:
> > > > > > > > I feel like we should have separate deprecation
entries for the
> > > > > > > > i686 host support, and for qemu-system-i386
emulator binary, as
> > > > > > > > although they're related they are independant
features with
> > > > > > > > differing impact. eg removing qemu-system-i386
affects all
> > > > > > > > host architectures, not merely 32-bit x86 host, so
I think we
> > > > > > > > can explain the impact more clearly if we separate
them.
> > > > > > >
> > > > > > > Removing qemu-system-i386 seems ok to me - I think
qemu-system-x86_64 is
> > > > > > > a superset.
> > > > > > >
> > > > > > > Removing support for building on 32 bit systems seems
like a pity - it's
> > > > > > > one of a small number of ways to run 64 bit binaries on
32 bit systems,
> > > > > > > and the maintainance overhead is quite small.
> > > > > >
> > > > > > Note: We're talking about 32-bit *x86* hosts here. Do
you really think that
> > > > > > someone is still using QEMU usermode emulation
> > > > > > to run 64-bit binaries on a 32-bit x86 host?? ... If so,
I'd be very surprised!
> > > > >
> > > > > I don't know - why x86 specifically? One can build a 32 bit
binary on any host.
> > > > > I think 32 bit x86 environments are just more common in the
cloud.
> > > >
> > > > Can you point to anything that backs up that assertion. Clouds
I've
> > > > seen always give you a 64-bit environment, and many OS no longer
> > > > even ship 32-bit installable media.
> > >
> > > Sorry about being unclear. I meant that it seems easier to run CI in the
> > > cloud in a 32 bit x64 environment than get a 32 bit ARM environment.
> >
> > It's still doable ... but for how much longer? We're currently depending
on
> > Fedora, but they also slowly drop more and more support for this
> > environment, see e.g.:
>
> FWIW, we should cull our fedora-i386-cross.docker dockerfile and
> replace it with a debian i686 dockerfile generated by lcitool.
> There's no compelling reason why i686 should be different from
> all our other cross builds which are based on Debian. The Debian
> lcitool generated container would have access to a wider range
> of deps than our hand written Fedora one.
>
> >
https://www.theregister.com/2022/03/10/fedora_inches_closer_to_dropping/
>
> With regards,
> Daniel
... and is closer to where 32 bit is likely to be deployed which is
systems like e.g. raspberry pi os which until recently was only
32 bit.
32 bit ARM. How is that an argument for continued maintenance of 32 bit
x86?
If the argument goes like "32 bit x86 is easier to test in CI", then I
don't buy it. Testing 64 bit ARM + 32 bit x86 does not magically
replace testing 32 bit ARM.
The question to answer: Is 32 bit x86 worth its upkeep? Two
sub-questions: 1. Is it worth the human attention? 2. Is it worth
(scarce!) CI minutes?
I want to see an argument for benefits justifying the costs.
A benefit like "somebody out there might still want to use it" I'd value
at zero.