'C/C++ Projects' view hangs i there are more than 70k files in a working tree
This is discovered some file/code file generator generated large number of files in a cpp project.
When user tries to open the directory it has the large number of files it made the eclipse unresponsive for over 15 seconds.

Solution proposed:
Please check below PR for planned fix.
eclipse-platform/eclipse.platform.ui#810
JFace Viewr now has a viewer limit feature which allows it to display only limited number of items and then a special Item called ExpandNode. On Selection of ExpandNode then it populates the next 'limit' number of elements. This phase by phase population of elements keeps the UI responsive.
This limit can be configured in General Preference page. And you can set to any limit based on the computer capacity.