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It's the Memory Latency, Stupid

68 points • by ntur1337 • today at 6:38 PM • 16 comments • view on HN

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boricj • today at 7:38 PM

I work with another team at work that uses lots of message passing, C++ virtual methods in deeply nested class hierarchies, large DOMs and off-the-shelf C++ STL containers... on a STM32MP1, which has an in-order Cortex-A7 and a pittance of cache.

On the other hand, in my team I wrote my custom C++ STL containers that allocate inline, SAX-style processing libraries and an object pool with links that use index+generations like 2000s video games... on a STM32H5 with less than a megabyte of RAM.

Mechanical sympathy feels like a lost art to people I demonstrate it to... and I had to demonstrate to the first team with benchmark numbers that I would not be the bottleneck between us by orders of magnitudes.

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brcmthrowaway • today at 9:39 PM

https://people.freebsd.org/~lstewart/articles/cpumemory.pdf

Has anyone rewritten this for 2026?