Shell Script to look for all lines in a file having '500' in the 11 column taking too long to run

Question

I wrote the following script as a practice :

#!/bin/bash

MyFile=$1

while read p; do

error=$(echo $p | awk '{print $11}')

        if [ "$error" = "500" ]
        then
                echo $p
        fi

done < $MyFile

The problem is that the script runs slowly taking hours to complete, my setup :

• Ubuntu on Windows 10 (64 with intel i7 6400 2.80GHz and 8G Ram).

Is there an issue with my setup or with the logic of the script ? Thanks,

Answer 1

Using $( runs a subshell, so does the pipe |. It's better to do all the work in one shell or one language.

E.g. do all the work in awk:

awk '($11==500){print}' "$1"

Or without shelling out:

while read -a columns ; do
    [[ ${columns[10]} == 500 ]] && echo "${columns[@]}"
done < "$1"