How much memory do 10 million bools take up? Short answer 10MB. This is 8x as large as the number of bits that I actually care about. Details In Go all elements of a slice are addressable. The smallest addressable unit being the byte, a slice of bools looks in memory like a…

Some data is best modeled as a bit set. For example, the essential information about which students successfully passed a test, out of 3000 students, consists in 3000 bits (375 bytes only). It turns out that Go doesn’t have a Bitset type in the standard library! Abstract type: interface First, let’s say that…

Yesterday I opened the Logs page of my App Engine Standard application in the Google Cloud console to check a specific log, only to discover much more traffic than I expected. Confirmation in the App Engine “Summary” dashboard:

Have you ever tried to design an algorithm to solve a problem on an input of arbitrary length n, and nailed it in only O(n) running time? Sometimes it’s easy, like “Find the minimum in the following list of n integers” The inconvenient truth Most of the time you actually don’t end up…

gofmt is not only about formatting — TL;DR $ gofmt -w -r 'strings.Index(a, b) >= 0 -> strings.Contains(a, b)' . What I was trying to achieve Until recently, Javascript didn’t have the includes method to test if a string b is a substring of a string a. The idiomatic way to test this was if (a.indexOf(b) !== -1) { // b is a…

This story relates events that happened on September 26th, 2019. They are all true. A website that I built, “Programming Idioms”, hit the first page of the “orange site” (aka Hacker News). My cloud provider monitoring console let me find out if the sudden traffic had caused an outage or…

The Beta support for Go 1.11 on Google Cloud Functions has been announced last week. Here are a few details about the Dancing Gopher factory function that I tweeted about. First, it’s easier to have some code already working on my local machine, before throwing it to GCF. …

TL;DR migrating to the new runtime is a good idea, give it a try! I’ve been running a website on the App Engine standard go runtime for years (since ~2013), and I’ve always been thankful for how well it is managed by the cloud provider: What I deploy simply keeps…

In this article about the Go race detector, I emphasize that violating the Memory model with unprotected concurrent accesses is a serious error. I must add that fixing the data races doesn’t make a program execution trace deterministic. …