On 29. 11. 22, 10:17, Richard Biener wrote:
Croak on < "1.5" during runtime in glibc then and die. Still no point to pick arbitrary vX, provided there is still a heap of v2 out there.
What required cpu features do you have in your mind regarding the atomics and other minor details? We might need to require those instead.
cmpxchg16 was mentioned in that context
Which is very legible. Yet, despite my two CPUs are NOT so called "v2", they both support cmpxchg16 (cx16).
I think that even defaulting to -v2 is going to help some ISVs (since RHEL 9 now requires x86-64-v2), both in compatibility and performance.
I don't understand the compatibility point. With v1 we should be compatible "more", or not?
Well, if ISV builds their product on RHEL9 then they might hesitate to say it's certified for ALP since any "under the condition the HW can do -v2" will in practice be difficult to sell and support. And on the notion that -v2 is better than "-v0" they will likely refuse to build with that.
Citation needed regarding performance.
It always depends on the benchmark, but the more strong argument is marketing and manager perception.
Ah, I was so dumb and now I see -- it's only politics in it. And it affects community-based distro. Yes, I understand the SUSE's POV -- to sell, sell, sell. I also know, that managers always affected openSUSE in some manner. At least indirectly by e.g. providing HW, manpower etc. But this is sort of different. This appears to be a non-technical decision applied to _open_SUSE for reasons I still don't follow. And as a workaround, it seems it will result in building Tumbleweed exactly twice. Bah. OK. -- js suse labs