Working with big directories is painfull because while nautilus is scanning a directory (to get mime types, thumbnails, etc), its other windows are frozen.

For example :
- open a dir of 2000 text files in window A
- while the directory is loading in A, try to use another nautilus window B. it's frozen
- once the directory is loaded in A (the window is not empty anymore), cpu usage stays 100%. maybe nautilus is scanning files in that directory that are not currently displayed (thumbnails, preview) ?.
- try to close window A. nautilus hangs. window B is unusable. eventually, a popup about nautilus being unresponsive is raised.
- when A is closed, B unfreezes

Thanks