On Thu, 28 Jul 2022 11:44:03 +0000 (UTC) Richard Biener wrote:
Thus I would propose raising the x86_64 architecture level to x86-64-v2 for openSUSE Factory. v2 requires CMPXCHG16B, [SL]AHF, POPCNT and SSE4_2 (and the predecessor SSE extensions) but not AVX, BMI or FMA.
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Comments welcome.
Hi, Are there some data available about the actual benefit of this change? On the one hand I am very for making the best use of available CPU features. On the other hand I dislike to obsolete hardware which is still perfectly working and usable. I am aware that for specific types of applications, algorithms or calculations modern CPU features can bring a big benefit. But I assume that most users are not running this type of workload. I also experienced in the past that a self compiled kernel optimized for i586 on a Pentium had noticeable better performance then the original distribution kernel built for i386 for specific tasks. But I think with x86_64 there is already a huge improvement of common available CPU features, and that the additional added features since then have very limited benefit for standard software (common libraries, kernel, ...). Therefore I think it would really be important to have some data about the expected benefits for standard use cases on -v2 or -v3 CPUs. And yes, I have a machine which would be obsoleted by this change. Kind regards, Dieter