IntelliJ IDEA 2025.3 Help

Performance Tips

Here you will find a few tips about what you can do to improve the performance of IntelliJ IDEA with Scala Plugin.

Ensure there's enough memory

To view the current memory usage, right-click the status bar and enable Memory Indicator (or Find Action "CPU and Memory Live Charts"). If necessary, use Help | Change Memory Settings to increase the maximum heap size.

Make code highlighting-friendly

In the same way code has runtime performance, code has compile-time performance. "The laws of highlighting," just as the laws of physics, are real and should be respected for highlighting to be efficient. Please see the guidelines for how to make code highlighting-friendly.

Try Incremental Highlighting

When using the built-in highlighting, you can enable Settings | Languages | Scala | Editor | Incremental highlighting to highlight only what's visible. (Double-press Esc to highlight the entire file.) This helps reduce CPU, RAM, and battery use, especially in large complex files, and also increase responsiveness.

Use compiler-based highlighting without inspections

Using Settings | Languages | Scala | Editor | Error highlighting: Compiler helps with false errors in complex code, but in normal cases it's usually slower and consumes more resources. However, if you also Disable built-in inspections, this can help with CPU, RAM, and battery use in cases challenging for the built-in type inference.

Capture CPU and memory snapshots

Sometimes, performance issues are inherent and depend on the code. Other times, the cause is an inefficiency in the algorithms. Follow the guidelines for reporting performance problems to capture CPU and memory snapshots and post them to the issue tracker, which can help us diagnose and fix the issue.

Get in touch

If you have any questions, we'd be glad to answer them in the Scala plugin discord channel.

19 December 2025