gnuplot> plot 'amd64-core-i7-0prec.out' with lines lw 1 lt 1 title 'FreeBSD 10 + calloutng', 'head.txt' with lines lw 1 lt 3 title 'FreeBSD 10', 'ideal.txt' with lines lw 1 lt 7 title 'Optimal case'

gnuplot> set xlabel 'Expected sleep time (microseconds)'
gnuplot> set ylabel 'Actual sleep time (microseconds)'