#!/bin/bash

# Index variables
declare -i k l
declare -i j=0
# Number of tries for each size
declare -i lend=20
# Index for loop global size
declare -i kstart=1024*1024 # 1 MB = 2^20
declare -i kend=4*1024*1024*1024 # 4 GB = 2^32
# Factor between each loop size
declare -i factor=16 # 2^4
# Number of threads
declare -a nb_process=(1 2 4 8 16 32 64 128 256 512 1024 2048 4096)
# Compile Posix or Go version
if [[ -z $1 ]]
then 
  echo "Empty argument : set 'posix' or 'go'"
  exit
elif [[ $1 == posix ]]
then
  echo "Posix benchmark"
  # Delete previous 'results_benchmark_posix.txt' file
  rm -f results_benchmark_posix.txt
  # Compile with gcc
  gcc -lpthread pi_mc_pthread.c -o pi_mc
elif [[ $1 == go ]]
then
  echo "Go benchmark"
  # Delete previous 'results_benchmark_go.txt' file
  rm -f results_benchmark_go.txt
  # Compile with go build
  go build pi_mc.go
else 
  echo "Invalid argument : set 'posix' or 'go'"
  exit
fi

# Main loop on global size
for ((k=kstart;k<=kend;k=k*factor))
do
  echo "Current size of loop : "$k
  # Loop on number of threads
  while [ "${nb_process[$j]}" != "" ]
  do
    echo "Number of threads : "${nb_process[$j]}
    sum1=0
    sum2=0
    sum3=0
    # Loop on number of tries
    for ((l=1;l<=lend;l++))
    do
      # Store various parameters and reults
      output1=$(echo "${nb_process[$j]}")
      output2=$(./pi_mc $output1 $k)
      output3[$l]=$(echo "$output2" | awk 'NR==1' | awk '{ print $6}')
      output4[$l]=$(echo "$output2" | awk 'NR==3' | awk '{ print $5}')
      output5[$l]=$(echo "$output2" | awk 'NR==3' | awk '{ print $7}')
      sum1=$(echo "scale=7; $sum1+${output3[$l]}" | bc)
      sum2=$(echo "scale=7; $sum2+${output4[$l]}" | bc)
      sum3=$(echo "scale=7; $sum3+${output5[$l]}" | bc)
    done
    # Compute mean values
    output_mean1=$(echo "scale=12; $sum1/$lend" | bc)
    output_mean2=$(echo "scale=12; $sum2/$lend" | bc)
    output_mean3=$(echo "scale=12; $sum3/$lend" | bc)
    # Final results
    time_final=$(echo "scale=12; $output_mean2+(10^(-6)*$output_mean3)" | bc)
    # Print results
    echo "$output1 $k $time_final $output_mean1" | awk '{printf("%10d %10d %13.12f %13.12f\n",$1,$2,$3,$4)}' \
          >> results_benchmark_$1.txt
    # Next number of threads
    j=$j+1
  done
# Blank line for separating blocks
echo " " >> results_benchmark_$1.txt
j=0
done