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Developer compensation has skyrocketed since the demise of the Google et al. wage-suppressing no-hire agreement , to the point where compensation rivals and maybe even exceeds compensation in traditionally remunerative fields like law, consulting, etc. In software, "senior" dev salary at a high-paying tech company is…
It's common to see people advocate for learning skills that they have or using processes that they use. For example, Steve Yegge has a set of blog posts where he recommends reading compiler books and learning about compilers. His reasoning is basically that, if you understand compilers, you'll see compiler problems…
There's a common narrative that Microsoft was moribund under Steve Ballmer and then later saved by the miraculous leadership of Satya Nadella. This is the dominant narrative in every online discussion about the topic I've seen and it's a commonly expressed belief "in real life" as well. While I don't have anything…
If I ask myself a question like "I'd like to buy an SD card; who do I trust to sell me a real SD card and not some fake, Amazon or my local Best Buy?", of course the answer is that I trust my local Best Buy 1 more than Amazon, which is notorious for selling counterfeit SD cards. And if I ask who do I trust more, my…
A common topic of discussion among my close friends is where the bottlenecks are in our productivity and how we can execute more quickly. This is very different from what I see in my extended social circles, where people commonly say that velocity doesn't matter . In online discussions about this, I frequently see…
On large platforms, it's impossible to have policies on things like moderation, spam, fraud, and sexual content that people agree on. David Turner made a simple game to illustrate how difficult this is even in a trivial case, No Vehicles in the Park . If you haven't played it yet, I recommend playing it now before…
Tavish Armstrong has a great document where he describes how and when he learned the programming skills he has . I like this idea because I've found that the paths that people take to get into programming are much more varied than stereotypes give credit for, and I think it's useful to see that there are many possible…
My mental model of CPUs is stuck in the 1980s: basically boxes that do arithmetic, logic, bit twiddling and shifting, and loading and storing things in memory. I'm vaguely aware of various newer developments like vector instructions (SIMD) and the idea that newer CPUs have support for virtualization (though I have no…
I try to avoid making predictions 1 . It's a no-win proposition: if you're right, hindsight bias makes it look like you're pointing out the obvious. And most predictions are wrong. Every once in a while when someone does a review of predictions from pundits, they're almost always wrong at least as much as you'd expect…
Jeff Atwood, perhaps the most widely read programming blogger, has a post that makes a case against using ECC memory . My read is that his major points are:
This is a pseudo-transcript for a talk on branch prediction given at Two Sigma on 8/22/2017 to kick off "localhost", a talk series organized by RC .
Any time you have a benchmark that gets taken seriously, some people will start gaming the benchmark. Some famous examples in computing are the CPU benchmark specfp and video game benchmarks. With specfp, Sun managed to increase its score on 179.art (a sub-benchmark of specfp) by 12x with a compiler tweak that…
This is one of those “N technical things every programmer must read” lists, except that “programmer” is way too broad a term and the styles of writing people find helpful for them are too different for any such list to contain a non-zero number of items (if you want the entire list to be helpful to everyone). So…
We spent one day 1 building a system that immediately found a mid 7 figure optimization (which ended up shipping). In the first year, we shipped mid 8 figures per year worth of cost savings as a result. The key feature this system introduces is the ability to query metrics data across all hosts and all services and…
In the fall of 2000, I took my first engineering class: ECE 352 , an entry-level digital design class for first-year computer engineers. It was standing room only, filled with waitlisted students who would find seats later in the semester as people dropped out. We had been warned in orientation that half of us…
It's generally accepted that any piece of software could be compromised with a backdoor. Prominent examples include the Sony/BMG installer , which had a backdoor built-in to allow Sony to keep users from copying the CD, which also allowed malicious third-parties to take over any machine with the software installed…
When I ask people at trendy big tech companies why algorithms quizzes are mandatory, the most common answer I get is something like "we have so much scale, we can't afford to have someone accidentally write an O(n^2) algorithm and bring the site down" 1 . One thing I find funny about this is, even though a decent…
This somewhat widely cited post (I keep seeing it cited, anyway) suggests that dynamic languages and/or languages that represent things more concisely are more token efficient. It seems to be cited enough that LLM search results agree. For example, when I searched for "dynamic vs static language token cost" (no…
This is an excerpt from an internal document David Mackey and I co-authored in April 2019. The document is excerpted since much of the original doc was about comparing possible approaches to increasing efficency at Twitter, which is mostly information that's meaningless outside of Twitter without a large amount of…
My hobby : opening up McIlroy’s UNIX philosophy on one monitor while reading manpages on the other.
In the classic 1986 essay, No Silver Bullet , Fred Brooks argued that there is, in some sense, not that much that can be done to improve programmer productivity. His line of reasoning is that programming tasks contain a core of essential/conceptual 1 complexity that's fundamentally not amenable to attack by any…
It's really common to see claims that some meme is backed by “studies” or “science”. But when I look at the actual studies, it usually turns out that the data are opposed to the claim. Here are the last few instances of this that I've run across.
This is a psuedo-transcript for a talk given at Deconstruct 2019. To make this accessible for people on slow connections as well as people using screen readers, the slides have been replaced by in-line text (the talk has ~120 slides; at an average of 20 kB per slide, that's 2.4 MB. If you think that's trivial…
Once upon a time, my computer architecture professor mentioned that using a random eviction policy for caches really isn't so bad. That random eviction isn't bad can be surprising — if your cache fills up and you have to get rid of something, choosing the least recently used (LRU) is an obvious choice, since you're…
Out of context, you might think they were scouting actors or models, but these are baseball players ("A" is Lloyd Moseby, "B" is Jim Abbott, and "C" is Derek Jeter), ones that were quite good (Lloyd Moseby was arguably only a very good player for perhaps four years, but that makes him extraordinary compared to most…
There's a class of comment you often see when someone makes a popular thread on Mastodon/Twitter/Threads/etc., that you also see on videos that's basically "Why make a Twitter thread? This would be better as a blog post" or "Why make a video? This would be better as a blog post". But, these comments are often stronger…
This is an archive of the original "fsyncgate" email thread. This is posted here because I wanted to have a link that would fit on a slide for a talk on file safety with a mobile-friendly non-bloated format .
Typical server utilization is between 10% and 50%. Google has demonstrated 90% utilization without impacting latency SLAs . Xkcd estimated that Google owns 2 million machines . If you estimate an amortized total cost of $4k per machine per year , that's $8 billion per year. With numbers like that, even small…
An alternate title for this post might be, "Twitter has a kernel team!?". At this point, I've heard that surprised exclamation enough that I've lost count of the number times that's been said to me (I'd guess that it's more than ten but less than a hundred). If we look at trendy companies that are within a couple…
In early 2025, I started seeing people turn off their brain as they use LLMs 1 . They would have an LLM take an action (summarize text, write some code, etc.), and just assume that it worked 2 . This generally didn't work in early 2025 and the result was often quite silly.