Re: latency test results for armhf vs arm64?

[Lennart Sorensen <lsorense@csclub.uwaterloo.ca>]

On Sat, Jul 16, 2022 at 08:35:26PM +0200, Diederik de Haas wrote:
> Raspbian(.org) was created by Peter Green (plugwash) (and Mike Thompson who's 
> name is still attached to raspbian(.org)'s GPG key, but otherwise moved on) 
> precisely because the RPi 1 did not meet the armhf/armv7 qualifications that 
> Debian uses.
> The Raspberry Pi Foundation (RPF) started with (Debian's) armel (armv5) 
> architecture, but that was slow and didn't optimally use the HW that was 
> available on the RPi 1.
> 
> So Plugwash (and Mike) started a recompilation of the Debian archive which 
> makes better use of the HW available in the RPi 1. Confusingly, they labeled 
> it armhf, while it was and is NOT the same as Debian's armhf.
> To add to the confusion, RPF called their OS also Raspbian :-/
> 
> AFAIK it's still Plugwash that runs the buildd which compiles the packages for 
> Raspbian/RaspiOS, but those packages are now also mirrored on RPF servers/
> archives. That is still ~armv6 (+hardfloat+sth IIRC).
> 
> The RPi 2 (and newer) can run Debian's armhf (armv7).
> 
> The RPi 3 and newer can also run arm64 and that is the same as Debian's.
> 
> I am *quite* sure RaspiOS is not available in normal/Debian's armhf, but only 
> in their own armv6+ (but labeled armhf) and arm64.

Yeah looking at raspberrypi.com they seem to have 64 bit and 32 bit
builds.  The 32 bit is definitely armv6 since it says it is compatible
with all versions of the pi.  Pretty sure they have never done armv7
since that would just be what Debian already provides and would break
the Pi 0 and Pi 1 after all although the 2 would be happier.  It shoudl
happily run on a kernel that supports armv7 but it does mean user space
certainly isn't fully taking advantage of what a pi 2 or newer offers.

I certainly only see 2 flavours on the page.  The original armel I don't
think has been made for quite a few years at this point and proper armv7
armhf they have certainly never done either.  So they have 2 flavours:
armv6 and armv8.

-- 
Len Sorensen