Part 2 - How not to use AWK at http://blog.ashwanthkumar.in/2016/02/how-not-to-use-awk.html

2.sh

#!/bin/bash

PACKER_LOG_FILE=$1

awk -F, '{if($2 != "") { print $0}}' $PACKER_LOG_FILE | while read LINE; do
  BUILDER_NAME=$(echo $LINE | awk -F, '{print $2}')
  if [ "X$BUILDER_NAME" != "X" ]; then
    echo "found $BUILDER_NAME on $LINE"
  fi
done

2_run_output.log

brindavan:~ ashwanthkumar$ time ./parse-packer packer.log 
found hvm-builder on 1455261963,hvm-builder,artifact-count,1
found hvm-builder on 1455261964,hvm-builder,artifact,0,builder-id,mitchellh.amazonebs
found hvm-builder on 1455261964,hvm-builder,artifact,0,id,us-east-1:ami-abcd
found hvm-builder on 1455261964,hvm-builder,artifact,0,string,AMIs were created:nnus-east-1: ami-abcd
found hvm-builder on 1455261964,hvm-builder,artifact,0,files-count,0
found hvm-builder on 1455261964,hvm-builder,artifact,0,end
found pvm-builder on 1455261964,pvm-builder,artifact-count,1
found pvm-builder on 1455261964,pvm-builder,artifact,0,builder-id,mitchellh.amazonebs
found pvm-builder on 1455261964,pvm-builder,artifact,0,id,us-east-1:ami-efgh
found pvm-builder on 1455261964,pvm-builder,artifact,0,string,AMIs were created:nnus-east-1: ami-efgh
found pvm-builder on 1455261964,pvm-builder,artifact,0,files-count,0
found pvm-builder on 1455261964,pvm-builder,artifact,0,end

real	0m0.063s
user	0m0.036s
sys	0m0.032s