Intellij Debugger slow: Method breakpoints may dramatically slow down debugging

In IDEA 2017.1 Emulated Method Breakpoints were introduced: https://www.jetbrains.com/help/idea/using-breakpoints.html#method_breakpoint They allow using method breakpoints without the performance penalty. Enabled by default.

Turn off the method breakpoint from the debug panel. Here is a screenshot.

Turn off the method breakpoints. You can see all your breakpoints through Run | View Breakpoints (Ctrl - Shift -F8 )

From the JetBrains Team: "Method breakpoints will slow down debugger a lot because of the JVM design, they are expensive to evaluate. Remove method breakpoints and consider using the regular line breakpoints.". See more.

To make the long story short, it seems that the root issue is that Method Breakpoints are implemented by using JPDA's Method Entry & Method Exit feature. This implementation requires the JVM to fire an event each time any thread enters any method and when any thread exits any method.