Hi all, ok this is a thing that’s been bugging me for a long time.
Finally i’ve found the way to fix it without root permissions, sweet, i’ve been able to free almost 600mb :O

 STEP 1
Dial *#9900#
This will bring up the Sysdump

STEP 2
Hit the ‘Delete dumpstate/logcat‘ button. Hit OK on the confirmation dialog.

STEP 3
Scroll to the end of the screen and hit ‘Exit’

All i have to say is: FINALLY!
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