Quickly deleting large file

Deleting larger file takes time, but when we dont want the file, why shout be their waiting time to delete it.

These files i am deleting

-rw-r--r--  1 sanjeev.tripurari  1114871328  24931090000 Jun 13 17:28 words3.txt

-rw-r--r--  1 sanjeev.tripurari  1114871328  24931090000 Jun 13 17:28 words2.txt

Normal deletion

$ time rm -fv words2.txt 

words2.txt

real 0m0.672s

user 0m0.001s

sys 0m0.080s

copy /dev/null will make it zerobyte quickly and then delete 

$ time cp -v /dev/null words3.txt 

/dev/null -> words3.txt

real 0m0.321s

user 0m0.001s

sys 0m0.294s

$ time rm -fv words3.txt 

words3.txt

real 0m0.006s

user 0m0.001s

sys 0m0.003s