Defragmentation in Linux?

Sander Marechal published at LXer interesting observations on file defragmentation that is would be needed in Linux:

"I still wondered how on earth it was possible the 100k+ files in Gentoo’s portage system - updated every time I synchronize the portage tree - didn't fragment my filesystem. Or was my filesystem fragmented and did I not know? Only recently, I found a script that is actually able to put numbers to all this gut-feelings, and the results were quite surprising in my opinion."

Result: to achieve a notable fragmentation level it’s necessary to do utmost. File fragmentation mainly happens in filesystems that contain large files. Pretty interesting.

Full article is here, as well as testing script, also you're welcome to read LXer discussion on this. Script for defragmentation is available at this page.