I have this same problem with hundreds files only. Search (by double shift) usually work, but sometimes freeze whole IDE.
Sometimes is enough click double shift for this:
And you can use this:
java.lang.OutOfMemoryError: Java heap space
Dumping heap to /home/daniel/java_error_in_IDEA.hprof ...
Unable to create /home/daniel/java_error_in_IDEA.hprof: Plik istnieje
^CException in thread "TimerQueue" java.lang.OutOfMemoryError: Java heap space
A fatal error has been detected by the Java Runtime Environment:
SIGSEGV (0xb) at pc=0x00007fe1a2d57939, pid=20452, tid=0x00007fe11b813700
What issues you are experiencing? IDE crash? Freeze? Too slow search?
What exactly kind of search is slow/freezes/crashes? Find in path? Navigate to file/class/symbol? Find usages? Find implementations/descendants?
Find in path has nothing to do to stub indices.
For big projects it's reasonable to increase heap memory for JVM. By default it's 750mb.
Adjust "-Xmx" setting in file "idea64.vmoptions" or (idea.vmoptions for 32-bit JVM) which is located in the same directory as IDEA executable.
Search Everywhere is slowed down by "navigate to class" and "navigate to symbol" features which are too slow for large code bases such as Delphi libraries.
I've disabled them in this build, please check if it helps.