Bug#871835: speed up for debootstrap

[Thomas Lange]

I forget something. During the run of debootstrap, I observed via
repeated ps -efl calls that often perl is running for a longer
time. Then I tried to use strace to see which exec(ve) calls takes a
long time. But I didn't managed to find out, instead I saw read calls
taking long. So I decided to look at the perl code and what it was
reading.
Using strace I could also see which perl calls where executed several
times.
 
-- 
regards Thomas