Clear Linux Achieved Even More Performance Improvements During April

[Templar82]

What exactly prevents other distributions from building at least some critical packages this way?

I believe a lot of their changes require a reasonably modern processors (with SSSE4 support for example) and no other distro wants to limit their user base like that.

[Spooktra]

I believe a lot of their changes require a reasonably modern processors (with SSSE4 support for example) and no other distro wants to limit their user base like that.

That's not true, SSE4 (no such thing as SSSE4) has been around since the Penryn, you wouldn't be "limiting" your user base by requiring it for your distro. The reality is that compiling the whole distro with cpu specific optimizations does not have the performance benefits one would think, as evidenced by OpenMandriva:

https://www.phoronix.com/scan.php?page=article&item=openmandriva-40a-znver1&num=1

Here's the thing, assume you had a beafy 10C/20T cpu that supported AVX-512 and decided that you would compile your entire distro and all the applications with flags that enabled AVX-512 optimized code paths, one would think that this distro would scream, but I don't think it would, in fact in many workloads it would probably be slower and here's why:

There are only a limited number of overall resources, such as registers and cache, available on the processor, if everything from the kernel, to the desktop manager, to the GUI, to the API's, and the entire app are hitting up the SIMD units then the critical parts of the app that can benefit from the vectoization have to contend with the non-critical OS parts that do not benefit from vectorization. Apps like x265 and Intel's SVT encoders, that make heavy use of AVX-512 would run slower on such a distro.

[skeevy420]

I believe a lot of their changes require a reasonably modern processors (with SSSE4 support for example) and no other distro wants to limit their user base like that.

Sandy Bridge and up. It's AVX support they're after. IIRC, their compiler uses march=sandybridge mtune=skylake.

[Vistaus]

I understand the legal issues of distributing proprietary codecs

Intel has plenty of money to pay royalties.