Simple script that parses the output of ./hash-table-tester and checks if you pass the performance threshold.

check

#!/usr/bin/env bash

# Simple script for parsing the output of ./hash-table-tester and checking if
# your v2 performance relative to the base performance meets the threshold
# stated on Piazza.

# EXAMPLE USAGE: ./hash-table-tester -t 8 -s 50000 | ./check

BLACK=$(tput setaf 0)
RED=$(tput setaf 1)
GREEN=$(tput setaf 2)
END=$(tput sgr0)

# Capture the output as it comes in through stdin, but also echo it back out.
input=$(cat)
echo "${BLACK}${input}${END}"

# Extract and clean the usec numbers from the output.
base_usec=$(echo "$input" | awk '/Hash table base: .*/ {print $4}' | tr -d ',')
v2_usec=$(echo "$input" | awk '/Hash table v2: .*/ {print $4}' | tr -d ',')

# Get the number of cores being used.
num_cores=$(nproc)
echo "* You are currently running on ${num_cores} cores."

# Use bc to perform floating point arithmetic on the criterion formula.

# NOTE: If instructors ever change the formula, change this line to match it.
ratio_formula="${base_usec} / (${num_cores} - 1)"
base_ratio=$(echo "scale=2; ${ratio_formula}" | bc -l)
echo "* Your base performance ratio is: ${ratio_formula} = ${base_ratio}"

# Use ratio_formula instead of the formatted ratio to prevent rounding errors.
comparison_formula="${v2_usec} < (${ratio_formula})"
echo "* Testing v2 comparison expression: ${comparison_formula}"
result=$(echo "$comparison_formula" | bc -l)

# bc returns 1 if a comparison is true and 0 if it's false.
echo -n "* PASSED: "
if [ $result -eq 1 ]; then
    echo "${GREEN}true${END}"
else
    echo "${RED}false${END}"
    exit 1
fi