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Log(Graph): A Near-Optimal High-Performance Graph Representation (2018) [pdf]

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Re: Log(Graph): A Near-Optimal High-Performance Graph Representation (2018) [pdf]

#11

Earlier quoted context omitted.

Hah, "just" a reinvention of graph analysis with linear-algebra. That's a "paradigm shift." Check out the performance numbers from that youtube video for redis-graph versus other graph databases. Reformulation of graph algorithms as algebraic operations means a huge step up in abstraction, and optimization, and performance. GraphBLAS is what enables that. It's the difference between tensorflow and having to rewrite s…

I'm not asking the point of graphs, I'm asking what is actually new. Directed acyclical graphs have been around for ages, combining them with linear algebra is not new. Instead of actually explaining anything that is new, original, unique or just a general step forward, all the replies seem to be saying how silly it is for asking and how smart someone is for counting triangles.

Please take any single one of the sentences of my first paragraph above, to explain what's cool about the comment and the OP. Any one sentence would, if true, make this material far more worthy of hacker interest than the typical HN front page article. That the post above shows all of them makes this comment one of the better contributions to the site in the past week. I'm still making my way through all the material and without a doubt consider it the best information I've learned all week.

Re: Log(Graph): A Near-Optimal High-Performance Graph Representation (2018) [pdf]

#12

Earlier quoted context omitted.

Hah, "just" a reinvention of graph analysis with linear-algebra. That's a "paradigm shift." Check out the performance numbers from that youtube video for redis-graph versus other graph databases. Reformulation of graph algorithms as algebraic operations means a huge step up in abstraction, and optimization, and performance. GraphBLAS is what enables that. It's the difference between tensorflow and having to rewrite s…

I'm not asking the point of graphs, I'm asking what is actually new. Directed acyclical graphs have been around for ages, combining them with linear algebra is not new. Instead of actually explaining anything that is new, original, unique or just a general step forward, all the replies seem to be saying how silly it is for asking and how smart someone is for counting triangles.

Yes, graphs have been around for ages. They're as old as trees! ;-)

And you're right, first-year intro courses present graphs as matrices, it's usually the first graph representation you learn.

However, historically that's not how graphs have been represented in commercial or open-source databases due to the computational complexity and impracticality of supporting different architectures. Many PhD research papers over the years have been about the task of creating one-off implementations for the new hardware of the day.

For an overview of GraphBLAS in the context Heterogeneous High-Performance Computing (HHPC) systems running on NVIDIA GPUs and Intel Xeon Phis, see the 2015 talk Scott McMillan (https://insights.sei.cmu.edu/author/scott-mcmillan/) gave at the CMU Software Engineering Institute:

Graph Algorithms on Future Architectures [video] https://www.youtube.com/watch?v=-sIdS4cz7-4

The figure cited by Scott McMillan in the CMU video is that each new hardware architecture implementation requires about 10,000 lines of code for BFS, and that's just one algorithm. The GraphBLAS standard makes this problem go away.

Furthermore, general on-demand access to GPU and TPU accelerators in cloud data centers just now became a thing. GraphBLAS will make it possible for non PhDs to run graph algos on clusters of accelerators in the cloud at supercomputer speeds.

https://cloud.google.com/gpu/

https://cloud.google.com/tpu/

Having the power of a Graph 500 (https://graph500.org) supercomputer at your fingertips and the ability to tap into that power on demand...well that's new! :-) And kinda crazy cool too, don't ya think?

P.S. A few years back, Jeremy Kepner did a mini-course on D4M (the precursor to GraphBLAS). The videos and material are on MIT OCW...

MIT D4M: Mathematics of Big Data and Machine Learning [video] https://www.youtube.com/watch?v=iCAZLl6nq4c&list=PLUl4u3cNGP...

Discussion: https://news.ycombinator.com/item?id=18105931

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