Stuff Yaron Finds Interesting

Technology, Politics, Food, Finance, etc.

Peripheral Bandwidths – PCIe, Infiniband, QPI, SATA, SAS, DMI/ESI & Ethernet

I’m trying to figure out just how much data I can move through a modern computer. To grok that I need to understand the bandwidth capabilities of the various types of peripherals one can attach to a modern computer. I therefore run through below what appear to be the main peripheral types and what kind of bandwidth they can maintain. Wikipedia has a great summary of the bandwidths of various technologies. Note however that the bandwidths listed in that article are raw (except, confusingly, when they are not) bandwidth, not data bandwidth, below I try to find numbers that represent actual data bandwidth.
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My computer memory cheat sheet

For various reasons I need to better understand the gory details of how modern hardware actually works, especially NUMA systems. My first stop on my tour of modern hardware is memory, specifically all the gory details of DDR3 memory (I’ll start worrying about DDR4 when I can buy it).
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