bradcray

8 ms·

1.
by bradcray 5mo ago
I disagree with the characterization that Chapel's parallelization features copied OpenMP without improving upon it: * Chapel's support for task parallelism predates OpenMP's (~2004 vs. ~2007, where Wikipedia cites Chapel&#x2
2.
by bradcray 5mo ago
Good point on my alluding to demerits of Fortran, C, and C++ without stating them, and thanks for clarifying your criticism. Using the four factors that I focused on as attractive features in new languages: Productivity: For me, while Fort
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by bradcray 5mo ago
I'd say that the opposite is more often the reality, which is why HPC systems tend to have high-bandwidth, low-latency networks.
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by bradcray 5mo ago
The evolution of C, C++, and Fortran is touched on in a sidebar, although admittedly very briefly: > Champions of Fortran, C++, MPI, or other entries on this list could argue that…
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by bradcray 5mo ago
Author here: I didn't go into more detail on this than https://chapel-lang.org/blog/posts/30years/#maybe-hpc-doesnt... because I felt like the article was long enough already and that I'd recently c
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by bradcray 1y ago
@yubblegum: I'm afraid we don't have an update on support for Apple GPUs since last year's comment. While it comes up from time-to-time, nobody has opened an issue for it yet (please feel encouraged to!), and it isn't s
7.
by bradcray 1y ago
@yubblegum: I'm unfairly biased towards Chapel (positively), so won't try to characterize HN's opinion on it. But I did want to note that while Chapel's original and main reason for being is HPC, now that everyone lives
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by bradcray 2y ago
The ~10-minute video for this talk is here, if anyone's interested in the narrative behind the slides: https://www.youtube.com/watch?v=U8KM8wv32js
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by bradcray 3y ago
We agree that the placement of data is important for HPC programmers to control. Locales are the means of controlling such placement in Chapel, whether directly (as in this article’s simple examples) of via abstractions like distributed ar
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by bradcray 3y ago
That doesn't seem extreme to me, as I generally feel similarly. If you (or other readers) are genuinely interested in using Chapel with Metal, please open an issue on our GitHub repository capturing your request, as that would be valu
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by bradcray 3y ago
These are great questions, and ones we’re very curious about as well. I don’t believe that our current Chapel team has much experience programming NNs and LLMs, having focused on other areas. That said, I’m also not aware of any intrinsic
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by bradcray 3y ago
Chapel was designed for the high performance computing community where programmers often want full control over mapping their computations to their hardware resources without needing to rely on techniques like virtualization or runtime load
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by bradcray 3y ago
Sorry for what now appears to be a double-post. Engin had just registered for HN, hadn't seen his reply going through, so asked me to relay it. Re-reading this Q+A this morning, I also wanted to clarify one thing, which is that when a
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by bradcray 3y ago
@ColonelPhantom: Thanks very much for your questions. The following are answers I'm relaying from Engin Kayraklioglu, who heads up the Chapel GPU effort: Re Intel support: That's definitely in our plans. However, there are also
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by bradcray 3y ago
I would say Chapel was created less to replace MPI and more to provide a higher-level alternative to it that is amenable to compiler optimization.
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by bradcray 3y ago
Those interested in the intersection between Python, HPC, and data science may want to take a look at Arkouda, which is a Python package for data science at massive scales (TB of memory) at interactive rates (seconds), powered by Chapel: *
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by bradcray 3y ago
My answer would be that Chapel supports a partitioned global namespace such that a variable within the lexical scope of a given statement can be referenced whether it is local to that CPU's memory, stored on a remote compute node, or s
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by bradcray 3y ago
@cbkeller: Though MPI is dominant in HPC by a very large margin, it's definitely not the only game in town. SHMEM is an MPI alternative with a smaller but very dedicated following. UPC, Fortran 2008, UPC++, and Chapel are all alterna
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by bradcray 3y ago
My understanding is that the Julia Petaflops run executed a Julia program per node, communicating via MPI. For some, that's probably obvious/expected for HPC; for others, it might not be considered "pure Julia".
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by bradcray 3y ago
Thanks for the mention, @distortedsignal! Note that CHIUW 2023 is online and free, requiring just a quick Zoom registration from the URL above. Tomorrow's topics are more about reporting on cool things being done with the Chapel langu
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by bradcray 5y ago
@blueslurpee: I'm definitely biased, but agree that Chapel would be a fun language to explore, particularly if you're interested in looking at integrated task- and data-parallelism within a language or distributed computing with a
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by bradcray 5y ago
> Chapel, HPC language mostly sponsored by Intel and HPC Minor correction: Intel hasn't traditionally been a sponsor of Chapel (though we'd love to see that change). Chapel was pioneered at Cray Inc. and continues on even str
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by bradcray 6y ago
@mardifoufs: I realize that your point is that the Chapel webpage didn't answer this question clearly / concisely for you and agree that we could and should improve that. The observations in this thread have definitely helped giv
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by bradcray 6y ago
I think it's plausible you would want to use Chapel for every program you write. I definitely want to use it for every program I write, but I'm also biased. The main disincentive to doing so today is that Chapel is not nearly as
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by bradcray 6y ago
Arkouda [1], [2] is a recent and substantial example use of Chapel. It's a Python package that supports a subset of NumPy operations on distributed Terabyte-scale arrays implemented using a server written in Chapel. It currently invo
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by bradcray 6y ago
Chapel performance has improved by leaps and bounds over the past 5+ years, though link [2] above focuses on single-node performance whereas most the team's recent optimization efforts have been focused on improving distributed memory
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by bradcray 6y ago
Historically, Chapel had an effort to support mixed instruction sets within a single logical program, but this effort fell by the wayside due to the amount of effort required to maintain it, combined with the fact that it was virtually unus
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by bradcray 10y ago
kenko is correct that the 'config' keyword is what indicates that a symbol can receive a command-line override in Chapel. As others have suggested, we followed C's lead in interpreting 'const' as "Cannot be re