Assembly programming can be intimidating for people who have never looked into it any deeper than a glance, but giving that it underpins how the computers we use work it can be helpful having context in regards to what is actually being run by the CPU.
A catalogue of software constructs, languages, or APIs which are unexpectedly Turing-complete; implications for security and reliability.
TinyWM is a tiny window manager that I created as an exercise in minimalism. It is also maybe helpful in learning some of the very basics of creating a window manager. It is only around 50 lines of C. There is also a Python version using python-xlib.
My blog post on falling in love with Rust got quite a bit of attention – with many being surprised by what had surprised me as well: the high performance of my naive Rust versus my (putatively less naive?) C. However, others viewed it as irresponsible to report these performance differences, believing that these…
Linux TCP Tracepoints, and using them via bcc/eBPF.
Introduction This article gives an overview of LocustDB [1], a new and extremely fast open-source analytics database built in Rust. Part 1 gives some background on analytical query systems and my g…
You're probably reading this page because you've attempted to access some part of my blog (Wandering Thoughts) or CSpace , the wiki thing it's part of. Unfortunately you're using a browser version that my anti-crawler precautions consider suspicious, most often because it's too old (most often this applies to versions…
By a strange coincidence the news broke this morning that RHEL is deprecating KDE. The real surprise here is that RHEL supported KDE all. Back in the 90s they were entirely against KDE and put lots of effort into our friendly rivals Gnome. It made some sense since at the time Qt was under a not-quite-free licence and…
I’m often asked in my technical troubleshooting job to solve problems that development teams can’t solve. Usually these do not involve knowledge of API calls or syntax, rather some kind of insight into what the right tool to use is, and why and how to use it. Probably because they’re not taught in college, developers…
Subtitle: Making Windows Slower Part 3: Process Destruction In the summer of 2017 I wrestled with a Windows performance problem. Process destruction was slow, serialized, and was blocking the syste…
I’ve spent a good deal of my professional life arguing against using protobuffers. They’re clearly written by amateurs, unbelievably ad-hoc, mired in gotchas, tricky to compile, and solve a problem that nobody but Google really has. If these problems of protobuffers remained quarantined in serialization abstractions…
Every concurrency API needs a way to run code concurrently. Here's some examples of what that looks like using different APIs:
A few weeks ago I was looking at some of the performance metrics for my site. Specifically, I wanted to see how I was doing on our newest metric, first input delay (FID). My site is just a blog (and doesn’t run much JavaScript), so I expected to see pretty good results.
The Beav in all his geometric glory. Even though I have been using some Linux distribution or another pretty much daily for roughly two decades, I...
When you can’t remove an app which you installed just a few minutes ago, you know there’s something wrong. Here’s the solution, and why this is bad security.
As of last nightly (20181115100051), Firefox now supports Wayland on Linux, thanks to the work from Martin Stransky and Jan Horak, mostly.
On UNIX-like operating systems, userland processes invoke kernel procedures using the "syscall" feature. Each syscall is identified by a "syscall number" and has a short list of parameters, which both can vary between operating systems, hardware platforms, and configuration options.
tl;dr I found several bugs in apk, the default package manager for Alpine Linux. Alpine is a really lightweight distro that is very commonly used with Docker...
Pipelines - a guided tour of the new IO API in .NET, part 1 (part 2 here) About two years ago I blogged about an upcoming experimental IO ...
Rules of optimization: 1) Design for performance from day 1 2) Profile often 3) Be vigilant on performance regressions 4) Understand the data 5) Understand the HW 6) Help the compiler 7) Verify your assumptions Performance is everyone's responsibility https://t.co/CwwJffnHGz
Many seasoned engineers working in JVM based languages have seen errors like this: [error] (run-main-0) java.lang.OutOfMemoryError: unable to create native thread: [error] java.lang.OutOfMemoryError: unable to create native thread: [error] at java.base/java.lang.Thread.start0(Native Method) [error] at…
Comparison of cold start statistics for FaaS across AWS, Azure and GCP
Systemd has a remotely exploitable bug in its DHCPv6 client . That means anybody on the local network can send you a packet and take control...
