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Back in the day, I worked on this little project called Larrabee – which later turned into the Intel Xeon Phi coprocessor. It was an ambitious and exciting platform. It consisted of a ton of 512 bit wide instructions to operate like a lot of streaming GPU architectures, yet was fully general purpose x86.

It turned out that getting performance out of this hardware was difficult. In order to get the full potential of the hardware, you simply had to utilize the vector units. Without that, it is like writing a single threaded app on a 8 core system. Single SIMD lane operation just wasn’t going to cut it as was written about in 2017 International Journal of Parallel Programming article:

“Our results show that, although the Xeon Phi delivers a relatively good speedup in comparison with a shared-memory architecture in terms of scalability, the relatively low computing power of its computational units when specific vectorization and SIMD instructions are not fully exploited makes this first generation of Xeon Phi architectures not competitive”

Using the Xeon Phi Platform to Run Speculatively Parallelized Codes

The paper, and the host of others linked on the page as references, are a good read and gives some hints why fixed-function GPUs have an advantage when it comes to raw streaming throughput. Hint: cache and data flow behavior is as, if not more, important as utilizing vectorization in such architectures.

Ever want to know what it’s like to work in a game studio? Double Fine has released a 33 episode series called PsychOdyssey which shows them developing Psychonauts 2 over 7 years.

Watch it on the youtube link above, download the 4k version for free off Internet Archive,

Acerola created a graphics to text shader. He talks about a number of interesting techniques beyond just ASCII lookups such as: edge detection, depth color falloff, blooming and tone mapping, color tones, color quantization, and other filters, etc.
Definitely worth a watch and you can check out a good amount of his code on his github repro.

Mike Steward decided to recover the original Apollo guidance computer programs that landed man on the Moon in the 1960’s. Unfortunately some of them seem to have been lost to history.

It turns out, chunks of the original hardware still exist – such as the rope core memory which contained the programs. The next question is, how do you read these programs off 50 year old rope core memory hardware? This video below tells you how he did it!

He even wrote a web app that simulates how core memory works. We do a decent job recording history’s events, but I think it’s extremely cool that this kind of historical technical information is not being lost to the ages.

You can also check out the many other videos about the Apollo guidance computer in the other parts of his videos – or a previous article which has a super-awesome description of how Apollo computers work by Robert Wills.