Intel Fortran versus Fortran gfortran fastest programs Always look at the source code. These are only the fastest programs. Look at the other programs. They may seem more-like a fair comparison to you. reverse-complement source secs mem gz busy cpu load Intel Fortran 4.94 985,376 1019 5.28 95% 3% 3% 6% Fortran gfortran 35.67 767,984 772 37.48 100% 2% 3% 1% spectral-norm source secs mem gz busy cpu load Intel Fortran 2.07 1,764 638 8.29 100% 100% 100% 100% Fortran gfortran 4.12 1,160 638 16.08 97% 98% 99% 97% n-body source secs mem gz busy cpu load Intel Fortran 8.29 8 1524 8.61 1% 0% 2% 100% Fortran gfortran 14.04 1,088 1305 15.45 3% 0% 100% 7% fannkuch-redux source secs mem gz busy cpu load Intel Fortran 12.58 11,036 1158 50.21 100% 100% 100% 100% Fortran gfortran 16.51 10,252 1158 65.67 100% 99% 99% 99% fasta source secs mem gz busy cpu load Intel Fortran 3.35 8 1351 3.45 0% 0% 100% 3% Fortran gfortran 3.55 1,088 1351 3.63 1% 0% 1% 100% pidigits source secs mem gz busy cpu load Intel Fortran 1.74 4,012 981 1.79 0% 100% 0% 2% Fortran gfortran 1.75 3,660 981 2.06 3% 14% 100% 1% binary-trees source secs mem gz busy cpu load Intel Fortran 5.48 114,064 1148 16.65 65% 79% 89% 71% Fortran gfortran 4.87 112,276 1148 14.04 71% 73% 89% 56% mandelbrot source secs mem gz busy cpu load Intel Fortran 3.69 36,232 957 14.68 99% 99% 99% 100% Fortran gfortran 2.61 34,636 957 10.26 98% 97% 97% 100% regex-redux source secs mem gz busy cpu load Intel Fortran 1.73 175,952 2225 4.90 67% 62% 61% 94% Fortran gfortran Failed k-nucleotide source secs mem gz busy cpu load Intel Fortran Make Error Fortran gfortran Make Error Intel Fortran Intel(R) Fortran Intel(R) 64 Compiler for applications running on Intel(R) 64, Version 19.1.1.217 Build 20200306 Copyright (C) 1985-2020 Intel Corporation. All rights reserved. FOR NON-COMMERCIAL USE ONLY Fortran gfortran GNU Fortran (Ubuntu 9.2.1-9ubuntu2) 9.2.1 20191008 all Intel Fortran programs & measurements all Fortran gfortran programs & measurements