This bug was originally marked as duplicate of bug 171702, that is already resolved. This bug is still valid, so this seems to be another bug, but it might be related.
Build: NetBeans IDE 8.0 (Build 201403101706)
VM: Java HotSpot(TM) 64-Bit Server VM, 25.0-b70, Java(TM) SE Runtime Environment, 1.8.0-b132
sindisil: I attempted ctrl-space completion in a Java properties file containing roughly 6558 properties.
Maximum slowness yet reported was 32989 ms, average is 32989
Created attachment 147083 [details]
Last 3 reports (all from 8.0 and older) :
725533 - slow ruby parsing
725510 - slow scala editor (huge 304 seconds)
725477 - folding writing too much to messages.log (that is already in Bug
Sending to Scala for evaluation.