The Illusion of a Single System Image

Oxide and Friends Twitter Space: September 6th, 2021

Put the OS back in OSDI

We’ve been holding a Twitter Space weekly on Mondays at 5p for about an hour. Even though it’s not (yet?) a feature of Twitter Spaces, we have been recording them all; here is the recording for our Twitter Space for September 6th, 2021.

In addition to Bryan Cantrill and Adam Leventhal, speakers on September 6th included Dan Cross, Josh Clulow, Tom Lyon, Simeon Miteff, Daniel Maslowski, Matt Campbell and Moritz. (Did we miss your name and/or get it wrong? Drop a PR!)

Some of the topics we hit on, in the order that we hit them:

• Adam’s tweets on recording Twitter Spaces.
• Tweet on recovering a recording!
• [@4:57](https://youtu.be/PVJfqjJJCkg?t=297) Timothy Roscoe’s Keynote 
  • Screenshots teasing his slides
  • Conf video
• Complicated relationship with academia and industry 
  • [@8:09](https://youtu.be/PVJfqjJJCkg?t=489) Adam’s MS graphics experience
  • Bryan’s USENIX 2016 keynote ~1hr: A Wardrobe for the Emperor – Stitching Practical Bias into Systems Software Research 
    • Conferences as the publishing vector for CS research
• [@13:47](https://youtu.be/PVJfqjJJCkg?t=827) What a modern OS does > … accreted and not designed.
   > They were not designed, they congealed.
• [@17:10](https://youtu.be/PVJfqjJJCkg?t=1030) Rob Pike’s 2000 “Systems Software Research is Irrelevant” paper
  • The value of incremental improvements
• [@21:47](https://youtu.be/PVJfqjJJCkg?t=1307) Building on extant working components and interfaces 
  • Opaque, proprietary hardware
  • AMD Platform Security Processor > Artifacts of the OS implementation tend to have outsized impact > on overall system performance
• [@26:27](https://youtu.be/PVJfqjJJCkg?t=1587) Performance is not the only axis of a system 
  • Security, malleability, convenience, reliability
• [@31:12](https://youtu.be/PVJfqjJJCkg?t=1872) Specialization 
  • HarmonyOS, Fuchsia
  • Different chips performing different tasks
  • Firmware everywhere
  • Intel Optane
  • Intel 8051
• [@37:02](https://youtu.be/PVJfqjJJCkg?t=2222) Open hardware and firmware 
  • ARM Cortex-M0 > That’s why we land at incrementalism, we ossify at some boundary. > And it’s very hard to change things on either side without moving in lockstep.
• Tom: The PC architecture was a great thing, but now the OS vendors have abdicated any knowledge of the hardware. Give us UEFI and we don’t care what happens beneath that.
  • Should ARM have UEFI? (or something like it)
• [@45:29](https://youtu.be/PVJfqjJJCkg?t=2729) Developing hardware is still challenging, but has never been easier than today (especially low-speed) 
  • Tom’s tweet about parallels with homebrew computing in the 70’s
  • Precursor and Xous
• [@50:58](https://youtu.be/PVJfqjJJCkg?t=3058) Where will new systems development fit in with our existing (working) systems? 
  • Low-speed is an opportunity area
  • RISC-V for peripherals
• [@56:37](https://youtu.be/PVJfqjJJCkg?t=3397) Backwards compatibility seems to be more important than marginal gains: 
  • Shingled magnetic recording offered <25% density gain at the cost of compatibility
  • Optane: gains didn’t justify the cost
  • Smart NICs only made sense in hyperscale server fleets > Josh: If you’re going to change the programming model, you have to blow the doors off on at least one axis
• [@1:00:45] Moving management plane to a NIC. 
  • AWS Nitro implements this with a series of PCIe offload cards.
• [@1:01:22](https://youtu.be/PVJfqjJJCkg?t=3682) Abstraction boundaries not designed for the current circumstances 
  • Coordination problems between vendors
  • Vestigial components
  • AMI, AST2500
  • Arcane boot processes and shortcuts available for cloud compute 
    • xhyve
• [@1:08:57](https://youtu.be/PVJfqjJJCkg?t=4137) Removing things is so hard 
  • Things change given enough time
  • Graham Lee’s essay on legacy and software dependencies …and in the end will be the command line
  • If we got something wrong or missed something, please file a PR! Our next Twitter space will likely be on Monday at 5p Pacific Time; stay tuned to our Twitter feeds for details. We’d love to have you join us, as we always love to hear from new speakers!