In this article we’ll go on a journey from 4-bit microcontrollers to room-sized mainframes and learn how porting C to each of them helped people separate the essence of the language from the environment of its birth. I’ve found technical manuals and videos for this article to help bring each computer to life.
Back in 2015, I wrote a popular post comparing the performance of a number of microSD cards when used with the Raspberry Pi. In the intervening three years, the marketplace hasn't changed a ton, but there have been two new revisions to the Raspberry Pi (the model 3 B and just-released model 3 B+). In that article, I…
bpftrace (DTrace 2.0) for Linux 2018: the bpftrace front-end
A guide to a secure and streamlined installation of OpenBSD 6.4 on a laptop.
wingolog: article: spectre and the end of langsec
You have just made a Bitcoin transaction and you are eager to see if it appears in the next block. You know that the expected time between Bitcoin blocks is 10 minutes. You check the log of your Bitcoin node. It has been 7 minutes since the previous block. You recall that blocks occurrences in Bitcoin are a Poisson…
What do Photoshop, Matlab, Panic Transmit, and Eclipse have in common? They are among the 299 apps for which macOS applies compatibillity fixes.
Intro - Testing Google Sites and Google Caja In March 2018, I reported an XSS in Google Caja, a tool to securely embed arbitrary html/javascript in a webpage. In May 2018, after the XSS was fixed, I r
IP addresses & routing
As I was listening to Anil talk about daemons spawning processes and sysadmins killing them, I thought, "What a great user interface!" Imagine running around with a shotgun blowing away your daemons and processes, never needing to type kill -9 again.
In my last post I promised to give more details about some rabbit holes that I went down during the investigation, including page tables, locks, WMI, and a vmmap bug. Those details are here, along …
I have a gripe with the phrase
See the end of the post for an October 2018 bug fix update, or read the whole story: Flaky failures are the worst. In this particular investigation, which spanned twenty months, we suspected hardwa…
A while ago I did a blog post about how long DNS resolvers hold results in cache for, using RIPE Atlas probes testing against their default resolvers (in a lot of cases, the DNS cache on their modem/router).
We’ve all probably seen Java’s String comparison function before. It compares strings by the first differing character, falling back to the length difference when they are identical up to the end of the shorter string:
How does printf work behind the scenes
There’s fast and there’s fast. This post is about Anna*, a key/value database design from our team at Berkeley that’s got phenomenal speed and buttery smooth scaling, with an unpr…
I always love when I find a really dumb solution that works reliably to fix a problem that should never really be a problem in the first place. But having worked with audio devices before—though nothing nearly as complex as the AirPods—I am willing to cut Apple some slack in building a seamless aural experience with…
This week we discussed the IPFS whitepaper by Juan Benet in my Distributed Systems Seminar. Remember peer-to-peer systems? IPFS is "pe...
KPTI/KAISER Meltdown Initial Performance Regressions
I have pretty basic needs from my desktop. I do 99% of my work using just three programs: a terminal emulator, Emacs, and Firefox. I don't want a lot of bells and whistles in my desktop, and I really just want it to get out of the way so I can do my work.
I’ve been working on building a compacting garbage collector in Ruby for a while now, and one of the biggest hurdles for implementing a compacting GC is updating references. For example, if Object A points to Object B, but the compacting GC moves Object B, how do we make sure that Object A points to the new location?…
Note: If this topic has peaked your interest, you can join me for a Webinar on August 15 where I’ll dive deep into Cloud Native Operations with Kubernetes and CI/CD Pipelines. Peering into the crystal ball Kubernetes as a technology has been very important to my career this year, and will be even more so for next year…
I keep getting a lot of private emails about my previous post about the latest status of the Linux kernel patches to resolve both the Meltdown and …
