Posted 29 days ago. Visible to the public.

How to fix parallel_tests with Redis on powerful machines

When you have a powerful machine with 16 cores, you might run into an error like

Refusing to use Redis db#16 The Redis DB number should be between 2 and 15, since we're using db#1 for development and the default Redis config has 16 databases, starting with db#0.

The easiest way to fix this is limiting the number of parallel processes that are used in parallel cucumber runs.
To do this, you can set an environment variable in your ~/.bashrc:


By refactoring problematic code and creating automated tests, makandra can vastly improve the maintainability of your Rails application.

Owner of this card:

Daniel Straßner
Last edit:
29 days ago
by Daniel Straßner
About this deck:
We are makandra and do test-driven, agile Ruby on Rails software development.
License for source code
Posted by Daniel Straßner to makandra dev
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