Towards a performant, scalable, and consistent I/O subsystem for the Kestrel-3

27 Jul 2015

Today, I presented a tech-talk on what I’m currently thinking the Kestrel-3’s I/O architecture should be. I’m calling the I/O implementation “PatientIO”, as a pun on “RapidIO.” For the purposes of this talk, PatientIO and RapidIO can be thought of identically. PatientIO differs from RapidIO only in how device enumeration happens, and on supported interconnect media; however, these topics are not covered.

This talk covers the following topics:

  • Motivation and problem statement.
  • Very high-level overview of current solution.
  • Anticipated data rates.
  • Anticipated impact on CPU performance (it’s deleterious; however, it should still be usable).
  • Security — how I work to prevent RowHammer-like exploitation of the I/O interconnect.

You can view the slides here.

author

Samuel A. Falvo II
Twitter: @SamuelAFalvoII
Google+: +Samuel A. Falvo II

About the Author

Software engineer by day. Amateur computer engineer by night. Founded the Kestrel Computer Project as a proof-of-concept back in 2007, with the Kestrel-1 computer built around the 65816 CPU. Since then, he's evolved the design to use a simple stack-architecture CPU with the Kestrel-2, and is now in the process of refining the design once more with a 64-bit RISC-V compatible engine in the Kestrel-3.

Samuel is or was:

  • a Forth, Oberon, J, and Go enthusiast.
  • an amateur radio operator (KC5TJA/6).
  • an amateur photographer.
  • an intermittent amateur astronomer, astrophotographer.
  • a student of two martial arts (don't worry; he's still rather poor at them, so you're still safe around him. Or not, depending on your point of view).
  • a former semiconductor verification technician for the HIPP-II and HIPP-III line of Hifn, Inc. line-speed compression and encryption VLSI chips.
  • the co-founder of Armored Internet, a small yet well-respected Internet Service Provider in Carlsbad, CA that, sadly, had to close its doors after three years.
  • the author of GCOM, an open-source, Microsoft COM-compatible component runtime environment. I also made a proprietary fork named Andromeda for Amiga, Inc.'s AmigaDE software stack. It eventually influenced AmigaOS 4.0's bizarre "interface" concept for exec libraries. (Please accept my apologies for this architectural blemish; I warned them not to use it in AmigaOS, but they didn't listen.)
  • the former maintainer and contributor to Gophercloud.
  • a contributor to Mimic.

Samuel seeks inspirations in many things, but is particularly moved by those things which moved or enabled him as a child. These include all things Commodore, Amiga, Atari, and all those old Radio-Electronics magazines he used to read as a kid.

Today, he lives in the San Francisco Bay Area with his beautiful wife, Steph, and four cats; 13, 6.5, Tabitha, and Panther.