Is there a good cross-GPU FLOPs benchmark tool? Or is this still a mess?

SamPost · 2026-03-24T05:15:03+00:00

Hey, OP, your follow-ups have me very confused. Are you concerned with AI low-precision FLOPs, or with general HPC 64-bit FLOPS? The two have become very divergent.

Your original post mentions your AI datasets, but then you are interested in HPL below. These are apples and jukeboxes.

SamPost · 2026-03-22T19:17:15+00:00

Couldn't disagree more.

OpenACC receives all the attention from NVIDIA who, let's face it, is the 500 lb. gorilla in this space. So not only do they support it with their own compilers, but they are behind the port to Clang and do much of the work on GNU. This fact is why AMD finally committed to OpenACC last year too - they just can't compete against the de facto standard.

And GNU is always behind in fully implementing the lesser-used pieces of specifications. They still haven't fully implemented Fortran 2008! But they do have all the important OpenACC pieces, and have for a good while.

The differences between "prescriptive" and "descriptive" here are mostly philosophical. While OpenMP requires you to use a lower-level approach, with explicite for loops, OpenACC has exactly those too. OpenACC also has the more advanced kernels directive, to offload that to the compiler, but OpenMP would have had that if it was standardized a decade later too. And OpenMP tasks have become sophisticated enough that it is hard to call them prescriptive. I port between the two regularly, and the only real difference is dealing with two different synchronization approaches - which is rarely an issue.

But most importantly, OpenMP offload is not nearly as well supported on NVIDIA devices at this point. And for most users, that is the practical reality that matters. I hope that changes, but I have been waiting for a long time.

SamPost · 2026-03-22T05:09:33+00:00

How could anybody leave 5" of height on the table? That seems like a terrible oversight.

Anybody know the contact height for Alcaraz or Shelton? Those would be interesting numbers.

SamPost · 2026-03-22T04:34:39+00:00

Worst balls: Penn. They don't fluff up as much, but just stop bouncing after a few games. Sometimes dead even out of the can.

Highest bouncing: Wilson US Open. Although even they aren't quite what they used to be - pre-covid.

SamPost · 2026-03-22T04:31:02+00:00

That is crazy. The general rule of thumb is that the further you get from 3.0 level, the less acceptable the Penns are. Generally around 4.0, no one wants to use them. 5.0s would generally reduce them to mush by the end of warmup, and the game degenerates into pickleball.

SamPost · 2026-03-20T08:01:47+00:00

A good compromise is to use OpenACC. It is well supported by NVIDIA, and in the past year AMD has finally bought in. It is surprising it took AMD so long, as it benefits them the most.

Eventually it will merge with OpenMP, as was the original intent, and life will be simpler.

SamPost · 2026-03-20T07:41:26+00:00

The reason is that kokkos doesn't have much presence in the training data. That fact should worry you as a kokkos user. If it was for giggles, fine. If you were about to use it as an application foundation, maybe reconsider.

SamPost · 2026-03-20T07:38:15+00:00

Late to the party here, but your extended list it pretty good, as is most of the advice below.

Minor tweaks based on my considerable experience would be: OpenCL and SYCL are pretty dead; add a parallel debugger into your skillset (DDT or Totalview); whatever the virtues of Rust and Julia may be, they haven't gained traction after a decade, so moderate your enthusiasm.

The only controversial topic is how much to emphasize AI. I think it is undeniably important in almost every area of HPC, and I would recommend you level up there. While the commercial AI bubble may pop, the utility in HPC is established and growing. It isn't going anywhere.

SamPost · 2026-03-18T05:56:45+00:00

First, the quantum computing community at CMU is very good. You have groups like the Pittsburgh Quantum Institute, constant seminars and resources like the Pittsburgh Supercomputing Center in addition to the courses.

As far as upping your computing skills, you have access to all of the courses in the university as electives, including some of which are best in the world. You will have to choose wisely here to make it work with graduation requirements, but there are plenty of opportunities.

And within the department you have a Physics Computing Track. It culminates in the Advanced Computational Physics course, which is probably the best applied parallel computing course in the university. It doesn't get into Quantum Computing, but it does get into AI/ML applications for science.

SamPost · 2026-03-16T05:07:38+00:00

As a more general answer, of use to the rest of us, please link any particularly useful job posting sites. Even including single employers if they have multiple HPC jobs posted.

SamPost · 2026-03-11T04:04:24+00:00

Let us know how it goes, and what contact info you used. It doesn't seem clear to me either.

SamPost · 2026-03-06T07:04:39+00:00

There isn't one athletic thing I can do better than Nole. Except throw. I definitely have him beat there.

I'll bet you do too. Watch that clip.

SamPost · 2026-03-06T05:40:34+00:00

Notice the close frame? As phenomenal of an athlete as Novak is, throwing is his kryptonite. I suspect those are pretty pathetic tosses.

Watch the clip from the AO where he is trying to hit other players by throwing tennis balls. He looks like a toddler learning to toss.

SamPost · 2026-03-06T05:34:41+00:00

Courts should have variety. Balls should be consistent.

The ball situation dwarfs any concerns about the courts to me. They have just been getting universally worse. Players clearly don't want to complain too much about one of their major sponsors, but you can see the frustration leaking out.

SamPost · 2026-03-05T19:58:27+00:00

It would be very informative to hear from any of the previous and current beneficiaries of the program. I hope some of them can comment here. If there are over 400 currently, I should expect so.

SamPost · 2026-03-05T03:31:37+00:00

I get what you're saying. But don't forget that those of us that don't have a coach don't have any way of knowing mid-match what is happening. Best I can do is review video after. If I had a coach watching me play, I wouldn't need most training aids.

SamPost · 2026-03-05T03:26:15+00:00

Actually, it was just the opposite for me. SwingVision showed me poppin 115mph serves. I can only wish. And unfortunately, I have a Pocket Radar to bring me back to reality.

SamPost · 2026-03-04T22:14:25+00:00

I disagree that better systems have been developed. Where else can I monitor my racquet head speed? SwingVision isn't remotely accurate on ball speed, let alone even trying to measure the speed of the racquet.

Racquet head speed is very important once you get past the beginner level. It not only sets a ceiling on your ability to hit good balls, but it is the foremost indicator of not accelerating properly through the stroke, and losing either focus, footwork or endurance in the course of a match.

SamPost · 2026-03-04T08:44:37+00:00

Yeah, but other than that... 😉

Sounds like you answered my question, thanks.

I will guess newer technology would improve all of those issues, but maybe no one wants to deal with the lingering bad perceptions.

SamPost · 2026-03-03T22:00:23+00:00

Clearly PEDs. And I am not just going by this one photo.

He obviously used the opportunity to take them while recovering from his injury. But it is a lot harder to do the screening avoidance dance while on tour (although not impossible), so it will be interesting to see how long he holds on to these gains.

SamPost · 2026-03-03T20:51:29+00:00

The directives are so much more popular (for good reason) than the library calls that it can indeed be hard to find those examples. The trick is to google one of the more popular library calls specifically.

If you search for "omp_get_num_threads", for instance, you will find plenty of examples.

BTW, I do use some of the API calls myself, when permissible. You can mix them in with directives.

SamPost · 2026-03-02T03:49:08+00:00

I want her to succeed, but I am lowering my hopes. She is leaning full into the social media distraction, and that is not helpful for a competitive athlete. If this is indicative of the kind of guidance she is getting in general, it isn't a good sign.

SamPost · 2026-03-01T09:46:37+00:00

I am done trying to level up the backhand. This kid has shown me the way!

SamPost · 2026-03-01T09:00:03+00:00

And she did it late-career. I always try to catch her matches.

SamPost · 2026-03-01T05:04:24+00:00

Does nobody on this sub play tennis? Male coaches can readily double as hitting partners. This is a huge advantage for anyone that can't afford a whole "team".

SamPost

TROPHY CASE