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Three major tools that companies have to influence behavior are incentives, process, and culture. People often mean different things when talking about these, so I'll provide an example of each so we're on the same page (if you think that I should be using a different word for the concept, feel free to mentally…
A recurring discussion in Overwatch (as well as other online games) is whether or not women are treated differently from men. If you do a quick search, you can find hundreds of discussions about this, some of which have well over a thousand comments. These discussions tend to go the same way and involve the same…
This is basically an expanded explanation of what I did after reading this tutorial by Marwan Burelle and then sitting down and trying to write my own implementation, so the steps are going to be fairly similar. The main implementation differences are that my version is simpler and more vulnerable to memory…
A question I get asked with some frequency is: why bother measuring X, why not build something instead? More bluntly, in a recent conversation with a newsletter author, his comment on some future measurement projects I wanted to do (in the same vein as other projects like keyboard vs. mouse , keyboard , terminal and…
Someone : Did you hear that Facebook/Google uses a giant monorepo? WTF! Me : Yeah! It's really convenient, don't you think? Someone : That's THE MOST RIDICULOUS THING I've ever heard. Don't FB and Google know what a terrible idea it is to put all your code in a single repo? Me : I think engineers at FB and Google are…
We previously noted that, while it's easier than ever to hit a particular quality bar by having coding agents use effective test techniques, software quality seems to be getting worse , indicating that whatever defaults developers are using may not work very well. Here, we test if simple instructions to agents to use…
You don't have to be at a party to see this phenomenon in action, but there's a curious thing I regularly see at parties in social circles where people value intelligence and cleverness without similarly valuing on-the-ground knowledge or intellectual rigor. People often discuss the standard trendy topics (some recent…
What's the first thing you do when you find a bug or see a missing feature in an open source project? Check out the project page and submit a patch!
There's been a lot of talk about the vulnpocalypse, to which I don't have much to add because I'm not a security person, but I haven't seen much discussion on the closely related (and to be fair, less serious, issue), the benchmarkpocalypse.
I've seen all these studies that show how a 100ms improvement in page load time has a significant effect on page views, conversion rate, etc., but I'd never actually tried to optimize my site. This blog is a static Octopress site, hosted on GitHub Pages. Static sites are supposed to be fast, and GitHub Pages uses…
I've been using AI fairly heavily since last November and the whole thing is a funny experience . An agent will do something that, if a human did it, you'd immediately fire them. My reaction, of course, is to act as if this is great and spin up a thousand agents so they can do even more of that.
Here's a language that gives near-C performance that feels like Python or Ruby with optional type annotations (that you can feed to one of two static analysis tools ) that has good support for macros plus decent-ish support for FP, plus a lot more. What's not to like? I'm mostly not going to talk about how great Julia…
A statement I commonly hear in tech-utopian circles is that some seeming inefficiency can’t actually be inefficient because the market is efficient and inefficiencies will quickly be eliminated. A contentious example of this is the claim that companies can’t be discriminating because the market is too competitive to…
This is an archive of an old Google Buzz conversation (circa 2010?) on a variety of topics, including whether or not it's inevetible that a closed platform will dominate social.
I've been hearing this question a lot lately, and when I do, it reminds me how much I don't know. Here are some questions this question brings to mind.
How much overhead should we expect from enabling integer overflow checks? Using a compiler flag or built-in intrinsics, we should be able to do the check with a conditional branch that branches based on the overflow flag that add and sub set. Code that looks like
Here's the graph of a toy benchmark 1 of page-aligned vs. mis-aligned accesses; it shows a ratio of performance between the two at different working set sizes. If this benchmark seems contrived, it actually comes from a real world example of the disastrous performance implications of using nice power of 2 alignment…
Verilog is the most commonly used language for hardware design in America (VHDL is more common in Europe). Too bad it's so baroque. If you ever browse the Verilog questions on Stack Overflow , you'll find a large number of questions, usually downvoted, asking “why doesn't my code work?”, with code that's not just a…
In 1999, Butler Lampson gave a talk about the past and future of “computer systems research” . Here are his opinions from 1999 on "what worked".
We’re going to reproduce some results from papers on filesystem robustness that were written up roughly a decade ago : Prabhakaran et al. SOSP 05 paper , which injected errors below the filesystem and Gunawi et al. FAST 08 , which looked at how often filesystems failed to check return codes of functions that can…
Which is faster, keyboard or mouse? A large number of programmers believe that the keyboard is faster for all (programming-related) tasks. However, there are a few widely cited webpages on AskTog which claim that Apple studies show that using the mouse is faster than using the keyboard for everything and that people…
I recently had a problem where part of the solution was to do a series of pointer accesses that would walk around a chunk of memory in pseudo-random order. Sattolo's algorithm provides a solution to this because it produces a permutation of a list with exactly one cycle, which guarantees that we will reach every…
I love reading postmortems. They're educational, but unlike most educational docs, they tell an entertaining story. I've spent a decent chunk of time reading postmortems at both Google and Microsoft. I haven't done any kind of formal analysis on the most common causes of bad failures (yet), but there are a handful of…
Hardware performance “obviously” affects software performance and affects how software is optimized. For example, the fact that caches are multiple orders of magnitude faster than RAM means that blocked array accesses give better performance than repeatedly striding through an array.
I've been reading a lot of predictions from people who are looking to understand what problems humanity will face 10-50 years out (and sometimes longer) in order to work in areas that will be instrumental for the future and wondering how accurate these predictions of the future are. The timeframe of predictions that…
I see a lot of essays framed as writing advice which are actually thinly veiled descriptions of how someone writes that basically say "you should write how I write", e.g., people who write short posts say that you should write short posts . As with technical topics, I think a lot of different things can work and…
If you've followed any tech news aggregator in the past week (the week of the 24th of May, 2015), you've probably seen the story about how SourceForge is taking over admin accounts for existing projects and injecting adware in installers for packages like GIMP. For anyone not following the story, SourceForge has a…
This is a collection of information on severe ( SEV-0 or SEV-1 , the most severe incident classifications) incidents at Twitter that were at least partially attributed to cache from the time Twitter started using its current incident tracking JIRA (2012) to date (2022), with one bonus incident from before 2012. Not…
Why are people so concerned with hardware power consumption nowadays? Some common answers to this question are that power is critically important for phones, tablets, and laptops and that we can put more silicon on a modern chip than we can effectively use . In 2001 Patrick Gelsinger observed that if scaling continued…
The latest version of the Intel manual has a couple of new instructions for non-volatile storage, like SSDs . What's that about?