solaris 2.5.1 usparc 167mhz?? - SC4.0 cc -fast -Xa -xO5 For the ultra sparc, SunC 4.0 cc -fast -Xa -xO5, running 'des_opts' gives a speed of 475,000 des/s while 'speed' gives 417,000 des/s. I belive the difference is tied up in optimisation that the compiler is able to perform when the code is 'inlined'. For 'speed', the DES routines are being linked from a library. I'll record the higher speed since if performance is everything, you can always inline 'des_enc.c'. [ 16-Jan-06 - I've been playing with the '-xtarget=ultra -xarch=v8plus -Xa -xO5 -Xa' and while it makes the des_opts numbers much slower, it makes the actual 'speed' numbers look better which is a realistic version of using the libraries. ] options des ecb/s 16 r1 p 475516.90 100.0% 16 r2 p 439388.10 92.4% 16 c i 427001.40 89.8% 16 c p 419516.50 88.2% 4 r2 p 409491.70 86.1% 4 r1 p 404266.90 85.0% 4 c p 398121.00 83.7% 4 c i 370588.40 77.9% 4 r1 i 362742.20 76.3% 16 r2 i 331275.50 69.7% 16 r1 i 324730.60 68.3% 4 r2 i 63535.10 13.4% <-- very very weird, must be cache problems. -DDES_UNROLL -DDES_RISC1 -DDES_PTR