Today I Learned

Debugging Intellij IDEA Performance Issues

All of a sudden our work with the Intellij IDEA platform started to feel sluggish. Each code change caused delays that lasted multiple seconds. Observing the cpu activity we saw that it kept spiking at around 100% load. It was impossible to continue working like that so we proceeded to find out what exactly might be behind these massive spikes.

It turns out that Intellij IDEA has a pretty simple built in activity monitor (Activity Monitor under Help menu) to see what is going on at any given moment. When everything works smoothly the monitor shows something like this on our work computer:

Intellij IDEA Activity Monitor
Intellij IDEA Activity Monitor

We saw some specific plugins taking most of the load at the moments the lag spikes occurred. After going through all the enabled plugins and removing those that were not needed anymore we restarted IDEA and it was working smooth again. It took just a small review of the work setup to get back up to optimal speed. If you don't even notice anymore how sluggish your install of the program is or you feel like it could be faster then I suggest taking a few minutes to review the performance of your main working tool. It is definitely worth the time.