Ruby versus Matz's Ruby 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. binary-trees source secs mem gz busy cpu load Ruby 44.61 531,600 1096 125.16 67% 72% 60% 81% Matz's Ruby 1,268.05 839,888 400 1,281.19 60% 0% 40% 0% fannkuch-redux source secs mem gz busy cpu load Ruby 303.19 26,680 1444 1,169.40 100% 91% 98% 97% Matz's Ruby 6,692.98 19,320 1444 25,945.29 97% 99% 97% 96% mandelbrot source secs mem gz busy cpu load Ruby 335.33 66,188 931 1,339.92 100% 100% 100% 100% Matz's Ruby 4,299.88 68,672 931 17,193.33 100% 100% 100% 100% n-body source secs mem gz busy cpu load Ruby 374.51 25,668 1137 387.63 67% 20% 2% 14% Matz's Ruby 4,386.74 4,084 1137 4,426.81 65% 0% 0% 35% fasta source secs mem gz busy cpu load Ruby 51.74 123,240 1069 55.08 43% 44% 2% 17% Matz's Ruby 477.60 101,796 1020 486.43 13% 85% 0% 3% pidigits source secs mem gz busy cpu load Ruby 3.23 380,036 485 4.90 12% 50% 52% 37% Matz's Ruby 29.43 18,384 518 29.65 100% 0% 0% 0% spectral-norm source secs mem gz busy cpu load Ruby 150.32 26,188 839 585.35 97% 97% 97% 97% Matz's Ruby 973.55 21,068 839 3,842.21 99% 98% 99% 99% k-nucleotide source secs mem gz busy cpu load Ruby 103.71 400,128 859 377.05 95% 85% 95% 89% Matz's Ruby 314.56 127,080 644 1,036.20 93% 81% 82% 73% reverse-complement source secs mem gz busy cpu load Ruby 20.99 1,611,616 295 27.84 98% 7% 18% 9% Matz's Ruby 38.45 492,804 264 38.84 100% 0% 1% 0% regex-redux source secs mem gz busy cpu load Ruby 15.97 277,888 726 33.81 41% 76% 59% 36% Matz's Ruby Bad Output Ruby ruby 2.7.0p0 (2019-12-25 revision 647ee6f091) [x86_64-linux] --jit Matz's Ruby ruby 1.8.7 (2008-08-11 patchlevel 72) [x86_64-linux] So old that I haven't been able to get rubygems to work no backport, no gmp all Ruby programs & measurements all Matz's Ruby programs & measurements