Mesa Considers Raising CPU Support Baseline

[John_Samuel128]

So this is really only raising the default for 32-bit distros, which seems kind of pointless. These features are already enabled by default on x86-64, including AFAIU for 32-bit libraries.

If you're building a 32-bit distro you're probably doing it to support older hardware in which case you'll turn this feature off anyway. So I guess I don't understand why this change was made.

[skeevy420]

Actually, no. The article isn't just talking about SSE2 hardware. It also mentions SSE3. I think SSE2 is probably in the reasonable realm since there's so many x86-64 baselines everywhere, and probably not very many x86-64 processors that lack SSE2. So they are matching in that regard.

I also think that in the days we are in now where the cost of hardware is going up so much, it's worth considering not being in such a rush to cut people off when so many are clearly going to (if nothing else, being forced into) using their existing hardware longer - or perhaps even being forced into resurrecting a few old boxes if necessary. I know I did just that recently. SSE3 is probably too high for now.

If you go and read the MR, SSE2 is gonna happen. SSE3, maybe but leaning towards not. SSSE3, very likely not. But as for what is actually up for consideration, just SSE2, anything without that is ancient.

Of course you do, at least you were honest enough to state your meaning. People throw around the "ancient hardware" moniker to the point that it's weaponized.

I try to give clear and concise viewpoints in these kinds of talks. Aside from bullshit Atom CPUs that I don't think Intel should be making, everything from the past 10 years or so is AVX capable so that seems to be a decent place for a modern/legacy split. At some point we have to accept that hardware is old due to power usage, heat generation, and advancements or changes instructions. Plus, to me at least, anything beyond AVX seems to be an AVXBBQ with features coming and going and AMD and Intel doing just enough so that there isn't any one good, broad setting that covers all their new stuff. v3 and v4 are compromises around that.

I actually think the skip between v2 and v3 is too aggressive because v3 omits AVX-only systems like AMD Bulldozer and Intel Sandy Bridge. There should be 5 levels; bump the current 3 and 4 up one and the new 3 should be lowest common denominator feature-set between Bulldozer and Sandy Bridge.

I'm old enough to remember when we'd get new architecture bumps every 5-8 years. I think we're going on 20+ years now. A lot of advancements have happened in those 20+ years and it'd be nice to take advantage of them globally versus rocking performance crippling legacy compatible code and having to get optimizations manually from elsewhere. That's why I keep proposing using legacy built packages as the base and having the package manager use the best optimized repo for the local CPU. No one gets left behind and everyone gets to run code more optimized for their kind of system.

[Zan Lynx]

I also think that in the days we are in now where the cost of hardware is going up so much

Yeah, no.

I come from the days when a desktop PC cost $2,000. As far as I am concerned, that price never really went down. Not if you want a decent machine.

What changed is that these days you can get cheaper, crappier computers for a lot less. They aren't top of the line but they come in at about $500.

Or get a Raspberry Pi.

As far as I can tell GPU cost has gone up a lot. But if you wanted a cheap Intel or AMD system that is still very cheap.

[ezst036]

If SSE2 max isn't "old hardware" then I don't know what is. That's what the article is talking about.

Actually, no. The article isn't just talking about SSE2 hardware. It also mentions SSE3. I think SSE2 is probably in the reasonable realm since there's so many x86-64 baselines everywhere, and probably not very many x86-64 processors that lack SSE2. So they are matching in that regard.

I also think that in the days we are in now where the cost of hardware is going up so much, it's worth considering not being in such a rush to cut people off when so many are clearly going to (if nothing else, being forced into) using their existing hardware longer - or perhaps even being forced into resurrecting a few old boxes if necessary. I know I did just that recently. SSE3 is probably too high for now.

Personally, I think anything before AVX is old hardware.

Of course you do, at least you were honest enough to state your meaning. People throw around the "ancient hardware" moniker to the point that it's weaponized.

[angrypie]

If you're into "retrocomputing", building from source is the least of your troubles. The "average Joe" with an old computer should take a look at what Foone or LGR go through to revive those machines.

[Zan Lynx]

Average Joe does not know how to compile.

This kind of person should not be expecting their retro-computing experience to be trouble free. This is the kind of person that should buy a locked-down Chromebook and let Google manage it.

[tildearrow]

Yes, and those enthusiasts did not think it was too difficult to move the pin jumpers around on their Ethernet card and edit and recompile the driver.

Now these "enthusiasts" are upset they have to change default settings in a Makefile somewhere?

Average Joe does not know how to compile.

[txtsd]

How would I add these build flags on arch? Is it a meson flag?

https://github.com/archlinux/svntogit-packages/blob/packages/mesa/trunk/PKGBUILD

[angrypie]

Because it still works.

What next, people throwing away a SNES becaue it is old? Or a Airbus A330 because it is twenty years old? The problem is, that people feel the need or actual force to throw away smartphones, televisions and other stuff because it is older than 36 months.

Ideally CPU features get enabled at run-time (dlopen) or compile-time (GCC is your friendly helper). So modern system can go full speed an older systems can kept in use.

General consumer hardware is now designed to fail after a while. A brand new TV or smartphone isn't going to last more than a few years, and even if it does, manufacturers will release firmware updates to ensure it becomes shit. Tech-aware people might be able to revert it, but not your average consumer. These products are also designed to be impossible to repair.

PC components like motherboards, CPU and RAM are likely the only ones that increased reliability over time, which means that anything from 2009-ish onwards will greatly outlive its usefulness. I can't recall the last time I saw a dead CPU that wasn't DOA or was defective from the factory (like the speed-binned Zen1 CPUs and the wonderful segfaults they caused).

[hsci]

Why someone in 2021 should still use hardware of 20 years ago ?

Because it still works.

What next, people throwing away a SNES becaue it is old? Or a Airbus A330 because it is twenty years old? The problem is, that people feel the need or actual force to throw away smartphones, televisions and other stuff because it is older than 36 months.

Ideally CPU features get enabled at run-time (dlopen) or compile-time (GCC is your friendly helper). So modern system can go full speed an older systems can kept in use.