On Thu, 15 Dec 2011 22:18:18 +0000 Mark Shannon <mark@hotpy.org> wrote:
For the gcbench benchmark (from unladen swallow), cpython with the new dict is about 9% faster and, more importantly, reduces memory use from 99 Mbytes to 61Mbytes (a 38% reduction).
All tests were done on my ancient 32 bit intel linux machine, please try it out on your machines and let me know what sort of results you get.
Benchmark results under a Core i5, 64-bit Linux: Report on Linux localhost.localdomain 2.6.38.8-desktop-8.mga #1 SMP Fri Nov 4 00:05:53 UTC 2011 x86_64 x86_64 Total CPU cores: 4 ### call_method ### Min: 0.292352 -> 0.274041: 1.07x faster Avg: 0.292978 -> 0.277124: 1.06x faster Significant (t=17.31) Stddev: 0.00053 -> 0.00351: 6.5719x larger ### call_method_slots ### Min: 0.284101 -> 0.273508: 1.04x faster Avg: 0.285029 -> 0.274534: 1.04x faster Significant (t=26.86) Stddev: 0.00068 -> 0.00135: 1.9969x larger ### call_simple ### Min: 0.225191 -> 0.222104: 1.01x faster Avg: 0.227443 -> 0.222776: 1.02x faster Significant (t=9.53) Stddev: 0.00181 -> 0.00056: 3.2266x smaller ### fastpickle ### Min: 0.482402 -> 0.493695: 1.02x slower Avg: 0.486077 -> 0.496568: 1.02x slower Significant (t=-5.35) Stddev: 0.00340 -> 0.00276: 1.2335x smaller ### fastunpickle ### Min: 0.394846 -> 0.433733: 1.10x slower Avg: 0.397362 -> 0.436318: 1.10x slower Significant (t=-23.73) Stddev: 0.00234 -> 0.00283: 1.2129x larger ### float ### Min: 0.052567 -> 0.051377: 1.02x faster Avg: 0.053812 -> 0.052669: 1.02x faster Significant (t=3.72) Stddev: 0.00110 -> 0.00107: 1.0203x smaller ### json_dump ### Min: 0.381395 -> 0.391053: 1.03x slower Avg: 0.381937 -> 0.393219: 1.03x slower Significant (t=-7.15) Stddev: 0.00043 -> 0.00350: 8.1447x larger ### json_load ### Min: 0.347112 -> 0.369763: 1.07x slower Avg: 0.347490 -> 0.370317: 1.07x slower Significant (t=-69.64) Stddev: 0.00045 -> 0.00058: 1.2717x larger ### nbody ### Min: 0.238068 -> 0.219208: 1.09x faster Avg: 0.238951 -> 0.220000: 1.09x faster Significant (t=36.09) Stddev: 0.00076 -> 0.00090: 1.1863x larger ### nqueens ### Min: 0.262282 -> 0.252576: 1.04x faster Avg: 0.263835 -> 0.254497: 1.04x faster Significant (t=7.12) Stddev: 0.00117 -> 0.00269: 2.2914x larger ### regex_effbot ### Min: 0.060298 -> 0.057791: 1.04x faster Avg: 0.060435 -> 0.058128: 1.04x faster Significant (t=17.82) Stddev: 0.00012 -> 0.00026: 2.1761x larger ### richards ### Min: 0.148266 -> 0.143755: 1.03x faster Avg: 0.150677 -> 0.145003: 1.04x faster Significant (t=5.74) Stddev: 0.00200 -> 0.00094: 2.1329x smaller ### silent_logging ### Min: 0.057191 -> 0.059082: 1.03x slower Avg: 0.057335 -> 0.059194: 1.03x slower Significant (t=-17.40) Stddev: 0.00020 -> 0.00013: 1.4948x smaller ### unpack_sequence ### Min: 0.000046 -> 0.000042: 1.10x faster Avg: 0.000048 -> 0.000044: 1.09x faster Significant (t=128.98) Stddev: 0.00000 -> 0.00000: 1.8933x smaller gcbench first showed no memory consumption difference (using "ps -u"). I then removed the "stretch tree" (which apparently reserves memory upfront) and I saw a ~30% memory saving as well as a 20% performance improvement on large sizes. Regards Antoine.