For a while now when using Sublime Text the fans on my laptop would spin up rather loudly, indicating high CPU usage. Just now I found out the issue and solution(s): indexing.
To confirm that indexing is the issue, you can check Sublime Text’s Indexing Status at Help > Indexing Status
Solution 1: Turn off indexing
Turning off indexing immediately solved the issue for me. This is fixed by opening up Sublime Text’s preferences (on a Mac: Cmd + , ) and adding to the right windows (which overrides default settings):
Note that this solution affects the “Go to definition” function.
Solution 2: Exclude “heavy” directories
In Sublime Text’s preferences, add:
"folder_exclude_patterns": [ "node_modules", "a_heavy_directory_name" ]
The “Go to definition” function works with this solution.