I only get a 2x improvement when switching LANG on Redhat linux on EC2:
% export LANG=C % time grep done nohup.out | wc -l 152929
real 0m0.343s user 0m0.233s sys 0m0.112s
% export LANG=en_US.UTF-8 % time grep done nohup.out | wc -l 152931
real 0m0.771s user 0m0.673s sys 0m0.100s
% grep --version GNU grep 2.6.3
Author is using grep 2.5.3, I am using 2.6.3, so not testing the same thing.
I only get a 2x improvement when switching LANG on Redhat linux on EC2:
% export LANG=C % time grep done nohup.out | wc -l 152929
real 0m0.343s user 0m0.233s sys 0m0.112s
% export LANG=en_US.UTF-8 % time grep done nohup.out | wc -l 152931
real 0m0.771s user 0m0.673s sys 0m0.100s
% grep --version GNU grep 2.6.3
Author is using grep 2.5.3, I am using 2.6.3, so not testing the same thing.