[CoastalCoder]

I'm not sure it makes sense to pin this only on AMD.

Whenever you're writing performance-critical software, you need to consider the relevant combinations of hardware + software + workload + configuration.

Sometimes a problem can be created or fixed by adjusting any one / some subset of those details.

[hobofan]

If that's a bug that only happens with AMD CPUs, I think that's totally fair.

If we start adding in exceptions at the top of the software stack for individuals failures of specific CPUs/vendors, that seems like a strong regression from where we are today in terms of ergonomics of writing performance-critical software. We can't be writing individual code for each N x M x O x P combination of hardware + software + workload + configuration (even if you can narrow down the "relevant" ones).

[jpc0]

> We can't be writing individual code for each N x M x O x P combination of hardware + software + workload + configuration

That is kind of exactly what you would do when optimising for popular platforms.

If this error occurs on an AMD Cpu used by half your users is your response to your user going to be "just buy a different CPU" or are you going to fix it in code and ship a "performance improvement on XYZ platform" update

[CuriousCosmic]

Nobody said "just buy a different CPU" anywhere in this discussion or the article. And they are pinning the root cause on AMD which is completely fair because they are the source of the issue.

Given that the fix is within the memory allocator, there is already a relatively trivial fix for users who really need it (recompile with jemalloc as the global memory allocator).

For everyone else, it's probably better to wait until AMD reports back with an analysis from their side and either recommends an "official" mitigation or pushes out a microcode update.

[ansible]

The fix is that AMD needs to develop, test and deploy a microcode update for their affected CPUs, and then the problem is truly fixed for everyone, not just the people who have detected the issue and tried to mitigate it.

[hobofan]

Yeah, but even if you'd take this on as your responsibility (while it should really be the CPU vendor fixing it), you would like to resolve it much lower in the stack, like the Rust compiler/standard library or LLVM, and not individually in any Rust library that happens to stumble upon that problem.

[pmontra]

Well, if Excel would be running at half the speed (or half of LibreOffice Calc!) on half of the machines around here somebody at Redmond would notice, find the hardware bug and work around it.

I guess that in most big companies it suffices that there is a problem with their own software running on the laptop of a C* manager or of somebody close to there. When I was working for a mobile operator the antennas the network division cared about most were the ones close to the home of the CEO. If he could make his test calls with no problems they had the time to fix the problems of the rest of the network in all the country.

[richardwhiuk]

You are going to be disappointed when you find out there's lots of architecture and CPU specific code in software libraries and the kernel.

[hobofan]

That's completely fine in kernels and low-level libraries, but if I find that in a library as high-level as opendal, I'll definitely mark it down as a code smell.

[Pop_-]

It's a known issue for AMD and has been tested by multiple people, and by the data provided by the author. It's fair to pin this problem to AMD.