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Every blog post that took off on Hacker News, ranked by the votes of its best submission. 6,943 posts.

Systems & Performance
Any year
1142

How does rsync work?

This post is the third article in a series of blog posts about rsync, see the Series Overview. With rsync up and running, it’s time to take a peek under the hood of rsync to better understand how it works. How does rsync work? When talking about the rsync protocol, we need to distinguish between:

1150

A 100x speedup with unsafe Python

We're going to speed up some numpy code by 100x using "unsafe Python." Which is not quite the same as unsafe Rust, but it's a bit similar, and I'm not sure what else to call it... you'll see. It's not something you'd use in most Python code, but it's handy on occasion, and I think it shows "the nature of Python” from…

1151

A Real Life Off-by-One Error

The Championnats d’Europe d’Escalade (climbing) in Villars-sur-Ollon has just finished. I couldn’t make it to all the events, but did see the finals of the “Speed” event. It’s a series of head-to-head elimination races up a 15m tall wall, resulting in an eventual victor after enough rounds.

1166

How to build software like an SRE

I’ve been doing this “reliability” stuff for a little while now (~5 years), at companies ranging from about 20 developers to over 2,000. I’ve always cared primarily about the software elements I describe as living “outside” the application – like, how does it get its configuration? What kinds of instances does it run…

1169

The Journey Before main()

A while back, I worked on a RISC-V-based userspace simulator for fun. In doing so, taught myself a lot more than I wanted to know about what happens in-between when the Kernel is asked to run a program, and when the first line of our program’s main function is actually executed. Here’s a summary of that rabbit hole.