Re: Future of armv7

On Tue, 18 Nov 2025 01:56:08 +0000
Minsoo Choo <minsoochoo0122@proton.me> wrote:

> - Maintaining at least one 32-bit platform makes porting FreeBSD to new
> 32-bit platforms easier in future.
> 
> Following is why I decided to vote towards the removal.
> - Usage of armv7 hardwares have been quickly dwindling in the past few
> years. Since I started studying in univeristy, the only armv7 I've seen is
> ARM Cortex-M for old stm32 courses. Even including Cortex-M, I don't see
> anyone around me who uses armv7 in their project or work. stable/15 will
> give 3 more years of support for armv7, and I expect that people will use
> armv7 dramatically less by then.
> - Warner mentioned OOM issues. 32-bit architectures usually have maximum
> memory capacity of 4GB, and introducing another 32-bit architecture won't
> solve this problem (unless they come up with something like PAE, but why
> would anyone come up with PAE if there are 64-bit architectures?). Thus,
> claims like "maintain at least one 32-bit architecture for future 32-bit
> architecture" don't really make sense to me. Even if we assume there will be
> a revolutionary 32-bit platform that can replace all existing 64-bit
> platforms under special circumstances, how do we know when the day will
> come? People in this list have said that there might be a future 32-bit
> platform, but I haven't heard what the plan is if there is NO such
> architecture in future. How can we tell? When is the time to remove armv7 if
> we really don't see another 32-bit alternative for decades?
> - Cost of maintaining, testing, and releasing FreeBSD on these platforms. As
> FreeBSD build system encompasses different architectures and operating
> systems should abstract different hardwares, armv6 might affect code other
> than its own architecture-specific code, such as jemalloc that Warner have
> mentioned.

OOM and compiling is not an issue when the system is just target. For example,
in VM/clouds, even i386 images are used because they use less memory so you
can buy more of them for same price. Another target is embedded/IoT world:
while vast majority of constrained devices have less than dozen Kb of RAM
(see IEEE 802.15.4/6LoWPAN world, C2 class by RFC 7228), situation may change
towards 32-bits addressing in future when 32-bit may become more cheap than
current 32-bit architectures.

-- 
WBR, @nuclight