#!/bin/bash
# usage:
## both quoted and unquoted commands work~
##  measure_performance my_command -with -args
##  measure_performance "my_command -with -args"

cmd="$@" # da command as a string or as args
start_date=$(date)
start_unixseconds=$(date +%s)
poll_seconds=2
logfile=/tmp/sillylog.csv

# throw a fit if no args supplied
if [ -z "$1" ]; then
    echo 'USAGE: measure_performance "string_command-with -args"'
    exit 1
fi

echo "testing your gay little command $cmd"
# start times
start_unixmicroseconds=$(date +"%s%6N") # get start microseconds fast as possible before run
# run the command with pidstat monitoring it, using eval to handle strings and args methods
eval "pidstat -h -H -d -r -u -I $poll_seconds -e $cmd >> \"$logfile\""
# get exit code
ret=$?
# end times
## microseconds
end_unixmicroseconds=$(date +"%s%6N") # get dis fast for accuracy
duration_microseconds=$(($end_unixmicroseconds - $start_unixmicroseconds))
## seconds
duration_seconds=$(($duration_microseconds / 1000000)) # seconds = microseconds / 1,000,000

# remove lines starting with # (comments), empty lines, and those starting with Linux so its a pure csv
# then squash spaces and replace with commas
# them awk by delimiter comma to output
cat "$logfile" | sed '/^#\|^$\|^Linux/d' | tr -s ' ' ',' | awk -F, '{ cpup += $8; memk += $13; memp += $14; rkbs += $15; wkbs += $15 } END { print "\nCPU:",cpup/NR,"\nMemory Usage (KiB):",memk/NR,"\nMemory Usage %:",memp/NR,"\nKiB Read Per Second:",rkbs/NR,"\nKiB Written Per Second:",wkbs/NR }' #$1,$3,$8,$13,$14,$15,$16,$17 }'
# add footer
echo -e "Duration Seconds: $duration_seconds\nDuration Microseconds: $duration_microseconds\nReturn Code: $ret"