After a few weeks of investigating the Apple M1 GPU in January, I was able to draw a triangle with my own open source code . Although I began dissecting the instruction set, the shaders there were specified as machine code. A real graphics driver needs a compiler from high-level shading languages (GLSL or Metal) to a…
By segregating macOS background tasks on Efficiency cores, M1 Macs can run user apps unfettered on their Performance cores. And that feels really fast.
X11 client and server. DOS. Windows 3.1. All with preemptive multitasking.
How to put a price on the limits of knowledge
TL;DR Modern disks are so fast that system performance bottleneck shifts to RAM access and CPU. With up to 64 cores, PCIe 4.0 and 8 memory channels, even a single-socket AMD ThreadRipper Pro workstation makes a hell of a powerful machine - if you do it right! Update 1: Since 2021, networks have gotten faster and now…
In the late 1990s, the Windows Shell and Internet Explorer teams introduced a bunch of brilliant and intricate designs that allowed extension of the shell and the browser to handle scenarios beyond…
I’d recently bought a new XPS13 7390 (non 2-in-1) laptop. I had bought the 8GB variant, how hard could it be to upgrade?
The tool is great, but it uses perf to record and analyze profile data, and perf on Debian has a performance problem : when not linked against libbfd , it shells out to addr2line for every address it needs to look up. Thousands and thousands and thousands of incredibly short-lived processes.
Every developer should watch the 5 videos about DocC from WWDC. But it’s really a plaintive cry for help. Until Apple squares up and addresses the problem, it can only grow worse.
This post tells about my journey on fast-booting a Raspberry Pi 3 (RPI). In addition to that, some optimizations are discussed that can be applied to a Qt (QML) application. At the end, we will have a …
Performance comparison of counting and sorting word frequencies in various languages (Python, Go, C++, C, AWK, Forth, and Rust)
Linux in a Pixel Shader - A RISC-V Emulator for VRChat
This has been on my mind for a while, and with a couple of things lately stoking my ire (the NFT resurgence, and Signal integrating MobileCoin), I’ve finally pushed myself to put it into words.
One of the main reasons some people tend to avoid updating their PCs is that “it makes it slower”. Especially with Windows 10’s Software as a Service approach, where it gets the s…
Robert O'Callahan. Christian. Kiwi. Software guy. All content human-authored unless otherwise noted.
When I ask my colleagues why mmap is faster than system calls, the answer is inevitably “system call overhead”: the cost of crossing the…
After beginning a compiler for the Apple M1 GPU , the next step is to develop a graphics driver exercising the compiler. Since the last post two weeks ago, I’ve begun a Gallium driver for the M1, implementing much of the OpenGL 2.1 and ES 2.0 specifications. With the compiler and driver together, we’re now able to run…
Near the end of January I was pointed to a twitter thread where a Windows user with a powerful machine was hitting random hangs in explorer. Lots of unscientific theories were being proposed. I don…
How to free space without dropping indexes or deleting data
When a program is mostly just accessing memory randomly, a standard cost model is to count the number of distinct random accesses. The general idea is that memory access is much slower than most other computational tasks. Furthermore, the cost model can be extended to count "nearby" memory accesses as free. That is…
Recently, I’ve come across a not so efficient implementation of a isEven function (from r/programminghorror ).
Let’s compare the performance of all supported runtimes + 2 custom runtimes (Rust and GraalVM).
This post contains my own opinions, not the opinions of my employer or any open source groups I belong or contribute to.
The primary admin account on an M1 Mac is its Owner, responsible for authorising the installation and use of second operating systems. Here’s what can go wrong with Ownership.
A lot of programmers believe that compilers are magic black boxes in which you put your messy code in and get a nice optimized binary out. The hallway philosophers will often start a debate on which language features or compiler flags to use in order to capture the full power of the compiler’s magic. If you have ever…
