WebStorm High Memory Usage: Increase Heap Size
Quick answer
If WebStorm warns about low memory or lags, raise the heap in Help | Change Memory Settings (the -Xmx JVM option) and restart.
Most likely fix: Change memory settings
How to fix it
Try these in order — the most common fix is first.
1. Change memory settings
- Go to Help | Change Memory Settings
- Set the amount of memory to allocate
- Click Save and Restart
Did this fix it?2. Edit custom VM options
- Go to Help | Edit Custom VM Options (Configure | Edit Custom VM Options on the Welcome screen)
- Add one option per line, for example -Xmx2048m
- Do not edit the default .vmoptions files; updates replace them
Did this fix it?3. Watch usage
- Right-click the status bar and select Memory Indicator
- Use -XX:NewRatio 1 if you often open new files or switch projects
Did this fix it?
Symptoms
Low memory warning (free heap under 5% after garbage collection), freezes, and stutter on large projects.
Why it happens
- Heap limit too low for the project size
- Many files open or frequent project switching
- Large files opened in the editor
This guide also covers
- webstorm increase memory
- webstorm high memory usage
- webstorm xmx
- webstorm out of memory
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