Questions[defrag](ubuntu)

I'm looking for a tool that can give me a visual representation of my ext4 fragmentation. Something similar to how Defraggler, Puran Defrag, and many others (UltraDefrag being the best) display your disk... (most good UIs display the files in the block you're hovering your mouse over)

Is there anything related for Linux?

I want to watch my disk and see just how "unneeded" defragmentation really is.

I don't want to use e4defrag, because I'm not sure it can show me what exactly it's doing to my disk.

EDIT (2021): it would seem a similar, less popular, question has been asked 3 years before this question with suggested tools: https://unix.stackexchange.com/questions/30743/is-there-a-tool-to-visualize-a-filesystem-allocation-map-on-linux

I don't want any answer saying that there's no need, please!

I have my home directy encrypted with ecryptfs. Does ecryptfs lead to fragmentation?

I have the feeling that reading files, displaying folders and login became continuously slower and slower (although it was not noticeably slow at the beginning). The hard disk makes a lot of seek noise even if I open only a text file. In /home/.ecryptfs I see many big archives (that probably contain the encrypted files), so I'm wondering if Linux file system online defragmentation gains anything here.

What options do I have to increase performance? Should I decide whether I maybe better do without encryption?

I want defragment my root ext4 partition after upgrade to 10.10. But I can't find e4defrag in standart repos. May I build it from source? And is it safe for use?

UPD: Now in 12.04, we have e4defrag in repos. Just tried it, and it works well! I see some speed improvement. Simply run e4defrag /dev/sda1

Why is defragmenting unnecessary in Ubuntu?