Track down race conditions with Go
Programming Snapshot – Racing Goroutines

© Lead Image © alphaspirit, 123RF.com
If program parts running in parallel keep interfering with each other, you may have a race condition. Mike Schilli shows how to instruct the Go compiler to detect these conditions and how to avoid them in the first place.
If programmers are not careful, program parts that are running in parallel will constantly get in each other's way, whether as processes, threads, or goroutines. If you leave the order in which system components read or modify data to chance, you are adding time bombs to your code. They will blow up sooner or later, leaving you with runtime errors that are difficult to troubleshoot. But how do you avoid them?
The common assumption that components will run in the same order that a program calls them is a fallacy – one easily refuted with an example such as in Listing 1. But coincidence can also be a factor. It is quite possible for something to work once but then crash after a small, and often unrelated, change to the code. The load on the system you are using can also play a role: Something may work flawlessly in slack times but fall apart unexpectedly under a heavy load.
The fact that unsynchronized goroutines do not run in the order in which they are defined, even if the program starts them one after the other, is nicely illustrated by Listing 1 [1] and the output in the upper part of Figure 1. Although the for
loop starts goroutine
first, followed by 1
, then 2
, and so on, as defined by the index numbers in i
, the upper part of Figure 1 makes it clear from the compiled program's output that chaos reigns, and the goroutines write their messages to the output as a wildly confusing mess.
[...]
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.

News
-
System76 Releases COSMIC Alpha 7
With scores of bug fixes and a really cool workspaces feature, COSMIC is looking to soon migrate from alpha to beta.
-
OpenMandriva Lx 6.0 Available for Installation
The latest release of OpenMandriva has arrived with a new kernel, an updated Plasma desktop, and a server edition.
-
TrueNAS 25.04 Arrives with Thousands of Changes
One of the most popular Linux-based NAS solutions has rolled out the latest edition, based on Ubuntu 25.04.
-
Fedora 42 Available with Two New Spins
The latest release from the Fedora Project includes the usual updates, a new kernel, an official KDE Plasma spin, and a new System76 spin.
-
So Long, ArcoLinux
The ArcoLinux distribution is the latest Linux distribution to shut down.
-
What Open Source Pros Look for in a Job Role
Learn what professionals in technical and non-technical roles say is most important when seeking a new position.
-
Asahi Linux Runs into Issues with M4 Support
Due to Apple Silicon changes, the Asahi Linux project is at odds with adding support for the M4 chips.
-
Plasma 6.3.4 Now Available
Although not a major release, Plasma 6.3.4 does fix some bugs and offer a subtle change for the Plasma sidebar.
-
Linux Kernel 6.15 First Release Candidate Now Available
Linux Torvalds has announced that the release candidate for the final release of the Linux 6.15 series is now available.
-
Akamai Will Host kernel.org
The organization dedicated to cloud-based solutions has agreed to host kernel.org to deliver long-term stability for the development team.