When any workspace of the eclipse is closed without closing all its editors and again opens the same workspace, it opens all the editors again which were opened at the time of closing. This might cause slow down the starting of the eclipse. So it is better to close all the opened editors before closing the workspace.
All open editors can be closed automatically with the closing of the eclipse workspace.
How to Do:
Go to the menu item Window -> Preference, Preference window will open then check the checkbox in the editor tab as shown in the figure below.