On Wed, Apr 27, 2016 at 05:04:38PM +0100, Gordan Bobic wrote:
>
>Maybe that's something that CentOS have added (don't know, haven't
>looked), RHELSA doesn't support it that I'm aware of and they're
>definitely only 64K page size. The biggest change is in rpm and the
>arch mappings there.
They might not support it, but it most certainly works. There are no
changes specific to this that I can find in CentOS. All I changed was
rebuilt the host kernel with 4KB pages and ARM32 support (still an
aarch64 kernel). C7 armv7hl guest is completely unmodified apart from
the /etc/rpm/platform being set explicitly.
The main point being that the original assertion that making this
work would require rpm, yum, packagekit, mock and other code changes
doesn't seem to be correct based on empirical evidence.
It may work with rpm, but, as per the original post, dnf does not
support it, and dnf should not support it as long as Fedora
does not support a 32 bit userspace on aarch64.
Despite Linus' words of wisdom to the contrary over the years. :-(
Linus is not God, and we'd rather support as broad as possible a
range of hardware.
>Yes, because the instructions can be dealt with by the
hypervisor
>whether through emulation, or some other mechanism.
If it's going to run in emulation you might as well run it on
some highest end possible x86 hardware, it'll be slightly less
excruciatingly slow. And last I checked, that still had issues
with availability of kernels and architectures emulated.
Actually, with kvm, you get pretty much the same speed as native
aarch64 vms. Also, server grade aarch64 h/w will give you
pretty decent performance. I'm less sure about SBCs; they're
dependent on the SoC used.
On the whole, 32 bit arm vms are going to have the same
performance on aarch64 as i686 on x86_64.
John.