Re: dropping 32-bit host support

[Thomas Huth]

On 16/03/2023 11.22, Andrew Randrianasulu wrote:
> чт, 16 мар. 2023 г., 12:17 Andrew Randrianasulu <randrianasulu@gmail.com 
> <mailto:randrianasulu@gmail.com>>:
>
>
>
>     чт, 16 мар. 2023 г., 11:31 Thomas Huth <thuth@redhat.com
>     <mailto:thuth@redhat.com>>:
>
>         On 16/03/2023 08.36, Philippe Mathieu-Daudé wrote:
>          > On 16/3/23 08:17, Andrew Randrianasulu wrote:
>          >>
>          >> чт, 16 мар. 2023 г., 10:05 Philippe Mathieu-Daudé
>         <philmd@linaro.org <mailto:philmd@linaro.org>
>          >> <mailto:philmd@linaro.org <mailto:philmd@linaro.org>>>:
>          >>
>          >>     Hi Andrew,
>          >>
>          >>     On 16/3/23 01:57, Andrew Randrianasulu wrote:
>          >>      > Looking at https://wiki.qemu.org/ChangeLog/8.0
>         <https://wiki.qemu.org/ChangeLog/8.0>
>          >>     <https://wiki.qemu.org/ChangeLog/8.0
>         <https://wiki.qemu.org/ChangeLog/8.0>>
>          >>      > <https://wiki.qemu.org/ChangeLog/8.0
>         <https://wiki.qemu.org/ChangeLog/8.0>
>          >>     <https://wiki.qemu.org/ChangeLog/8.0
>         <https://wiki.qemu.org/ChangeLog/8.0>>>
>          >>      >
>          >>      > ===
>          >>      > System emulation on 32-bit x86 and ARM hosts has been
>         deprecated.
>          >>     The
>          >>      > QEMU project no longer considers 32-bit x86 and ARM
>         support for
>          >>     system
>          >>      > emulation to be an effective use of its limited
>         resources, and thus
>          >>      > intends to discontinue.
>          >>      >
>          >>      >   ==
>          >>      >
>          >>      > well, I guess arguing from memory-consuption point on 32
>         bit x86
>          >>     hosts
>          >>      > (like my machine where I run 32 bit userspace on 64 bit
>         kernel)
>
>         All current PCs have multiple gigabytes of RAM, so using a 32-bit
>         userspace
>         to save some few bytes sounds weird.
>
>
>     I think difference more like in 20-30% (on disk and in ram), not *few
>     bytes*. 
>
>
> I stand (self) corrected on *on disk* binary size, this parameter tend to be 
> ~same between bash / php binaries from Slackware 15.0 i586/x86_64. I do not 
> have full identical x64 Slackware setup for measuring memory impact.
>
>
> Still, pushing users into endless hw upgrade is no fun:
>
> https://hackaday.com/2023/02/28/repurposing-old-smartphones-when-reusing-makes-more-sense-than-recycling/
>  >
>
> note e-waste and energy consumption

Now you're mixing things quite badly. That would be an argument in the years 
before 2010 maybe, when not everybody had a 64-bit processor in their PC 
yet, but it's been now more than 12 years that all recent Desktop processors 
feature 64-bit mode. So if QEMU stops supporting 32-bit x86 environments, 
this is not forcing you to buy a new hardware, since you're having a 64-bit 
hardware already anyway. If someone still has plain 32-bit x86 hardware 
around for their daily use, that's certainly not a piece of hardware you 
want to run QEMU on, since it's older than 12 years already, and thus not 
really strong enough to run a recent emulator in a recent way.

 Thomas