Bash Performance Test - Regex vs If/Else

perf.sh

# Requires: `bc`, `bash 4+`
#
# Example Output:
# Iterations 100,000
#   regex:   34.570s
#   if/else: 18.044s
#
# if/else is 47.8% faster than regex

declare -a arr=("/ock"
                "/ock.html" "/ock.json"
                "/ock?type=html" "/ock?type=json"
                "/favicon" "/favicon.ico")
LIMIT=100000
count=0

START=$(date +%s.%N)
printf "Iterations %'.f" $LIMIT
printf "\n  regex:   "
# REGEX
while [ $count -lt $LIMIT ]; do
  for i in "${arr[@]}"; do
    path="$i"

    if [[ "$path" =~ \/ock ]]; then
      if [[ "$path" =~ \/ock(\.)(.*) ]] ||
         [[ "$query" =~ (type\=)(html.*|json.*)? ]]; then
        if [[ "$type" == 'json' ]]; then
          continue
        elif [[ "$type" =~ plain|html ]]; then
          continue
        fi
      fi
    elif [[ "$path" == '/favicon' || "$path" == '/favicon.ico' ]]; then
      continue
    else
      echo 'unknown route'
      continue
    fi
  done
  let count=count+1
done
END=$(date +%s.%N)
REGEXDIFF=$(echo "$END - $START" | bc | awk -F"." '{print $1"."substr($2,1,3)}')
printf "%ss" $REGEXDIFF


START=$(date +%s.%N)
printf "\n  if/else: "
count=0
# if/else
while [[ $count -lt $LIMIT ]]; do
  for i in "${arr[@]}"; do
    path="$i"

    if [[ "$path" == '/ock' ]]; then
      continue
    elif [[ "$path" == '/ock.html' || "$path" == '/ock?type=html' ]]; then
      continue
    elif [[ "$path" == '/ock.json' || "$path" == '/ock?type=json' ]]; then
      continue
    elif [[ "$path" == '/favicon' || "$path" == '/favicon.ico' ]]; then
      continue
    else
      continue
    fi
  done
  let count=count+1
done
END=$(date +%s.%N)
IFELSEDIFF=$(echo "$END - $START" | bc | awk -F"." '{print $1"."substr($2,1,3)}')
printf "%ss\n\n" $IFELSEDIFF

DIFF=$(echo "$REGEXDIFF" - "$IFELSEDIFF" | bc -l)
DIVIDE=$(echo "$DIFF" / "$REGEXDIFF" | bc -l )
percentage=$(echo "$DIVIDE * 100" | bc)
echo -e "if/else is ${percentage::-19}% faster than regex"