AstonJ
Rails console using 100% CPU in dev (fix)
If you are experiencing Rails console using 100% CPU on your dev machine, then updating your development and test gems might fix the issue - at least that’s what worked for me. Here’s my old and new (old versions are commented out):
# group :development do
# # Access an interactive console on exception pages or by calling 'console' anywhere in the code.
# gem 'web-console', '>= 3.3.0'
# gem 'listen', '>= 3.0.5', '< 3.2'
# # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
# gem 'spring'
# gem 'spring-watcher-listen', '~> 2.0.0'
# end
group :development do
# Access an interactive console on exception pages or by calling 'console' anywhere in the code.
gem 'web-console', '>= 4.1.0'
# Display performance information such as SQL time and flame graphs for each request in your browser.
# Can be configured to work on production as well see: https://github.com/MiniProfiler/rack-mini-profiler/blob/master/README.md
gem 'rack-mini-profiler', '~> 2.0'
gem 'listen', '~> 3.3'
# Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
gem 'spring'
end
# group :test do
# # Adds support for Capybara system testing and selenium driver
# gem 'capybara', '>= 2.15'
# gem 'selenium-webdriver'
# # Easy installation and use of web drivers to run system tests with browsers
# gem 'webdrivers'
# end
group :test do
# Adds support for Capybara system testing and selenium driver
gem 'capybara', '>= 3.26'
gem 'selenium-webdriver'
# Easy installation and use of web drivers to run system tests with browsers
gem 'webdrivers'
end
Hope this saves someone a few hours of faffing around trying to troubleshoot the issue! 
Most Liked
ohm
It was probably listen. listen 3.3.0 fixed a lot of threading and process problems.
1
ohm
I’ve had some trouble with spring just sitting there as well. spring is used to preload the app, so you can tear down and start up a server or console snappy.
1
Popular Backend topics
New
New
New
New
During a recent code review I came across this scenario:
Code in review
if (input.getValue() != null) {
return Arrays.asList(value);...
New
If you are experiencing Rails console using 100% CPU on your dev machine, then updating your development and test gems might fix the issu...
New
I did not add this to a “this weekend I’ll learn” like my few other journals as I am decided on using this in the long term.
Last I work...
New
And the blog:
Rails has been unapologetically full stack since the beginning. We’ve continuously sought to include ever-more default an...
New
I’m experimenting with Hexagonal / Clean Architecture in Elixir. The classic Behaviour + Impl split works great for mocking and isolating...
New
New
Other popular topics
Write Elixir tests that you can be proud of. Dive into Elixir’s test philosophy and gain mastery over the terminology and concepts that u...
New
New
Curious to know which languages and frameworks you’re all thinking about learning next :upside_down_face:
Perhaps if there’s enough peop...
New
My first contact with Erlang was about 2 years ago when I used RabbitMQ, which is written in Erlang, for my job. This made me curious and...
New
From finance to artificial intelligence, genetic algorithms are a powerful tool with a wide array of applications. But you don't need an ...
New
I ended up cancelling my Moonlander order as I think it’s just going to be a bit too bulky for me.
I think the Planck and the Preonic (o...
New
Small essay with thoughts on macOS vs. Linux:
I know @Exadra37 is just waiting around the corner to scream at me “I TOLD YOU SO!!!” but I...
New
Hello everyone! This thread is to tell you about what authors from The Pragmatic Bookshelf are writing on Medium.
New
Intensively researching Erlang books and additional resources on it, I have found that the topic of using Regular Expressions is either c...
New
Author Spotlight:
Peter Ullrich
@PJUllrich
Data is at the core of every business, but it is useless if nobody can access and analyze ...
New
Categories:
Sub Categories:
Popular Portals
- /elixir
- /rust
- /wasm
- /ruby
- /erlang
- /phoenix
- /keyboards
- /python
- /js
- /rails
- /security
- /go
- /swift
- /vim
- /clojure
- /emacs
- /haskell
- /java
- /svelte
- /onivim
- /typescript
- /kotlin
- /c-plus-plus
- /crystal
- /tailwind
- /react
- /gleam
- /ocaml
- /flutter
- /elm
- /vscode
- /ash
- /html
- /opensuse
- /zig
- /deepseek
- /centos
- /php
- /scala
- /react-native
- /lisp
- /textmate
- /sublime-text
- /nixos
- /debian
- /agda
- /django
- /deno
- /kubuntu
- /arch-linux
- /nodejs
- /revery
- /ubuntu
- /manjaro
- /spring
- /diversity
- /lua
- /julia
- /markdown
- /v








