* Ingo Molnar <mingo@xxxxxxx> wrote: > Having said that, it would be nice if someone could test these two patches on a > modern AMD box, using the perf stat from here: > > http://people.redhat.com/mingo/tip.git/README > > cd tools/perf/ > make -j install > > and do something like this to test git gc's performance: > > $ perf stat --sync --repeat 10 ./git gc > > ... to see whether these speedups are generic, or somehow Intel CPU specific. To follow up on this angle, i've now tested both 'git gc' performance improvement patches on an Opteron box: # # Before: # Performance counter stats for './git gc' (10 runs): 6400.903957 task-clock # 0.977 CPUs utilized ( +- 0.09% ) 1,537 context-switches # 0.000 M/sec ( +- 3.12% ) 118 CPU-migrations # 0.000 M/sec ( +- 7.08% ) 40,879 page-faults # 0.006 M/sec ( +- 0.03% ) 14,768,724,649 cycles # 2.307 GHz ( +- 0.09% ) 9,185,135,676 instructions # 0.62 insns per cycle ( +- 0.08% ) 1,883,860,739 branches # 294.312 M/sec ( +- 0.16% ) 99,800,253 branch-misses # 5.30% of all branches ( +- 0.34% ) 6.548348691 seconds time elapsed ( +- 1.01% ) # # After: # Performance counter stats for './git gc' (10 runs): 6078.191492 task-clock # 0.979 CPUs utilized ( +- 0.09% ) 1,511 context-switches # 0.000 M/sec ( +- 2.85% ) 104 CPU-migrations # 0.000 M/sec ( +- 6.29% ) 41,410 page-faults # 0.007 M/sec ( +- 0.04% ) 14,024,602,415 cycles # 2.307 GHz ( +- 0.09% ) <not counted> stalled-cycles 11,364,757,635 instructions # 0.81 insns per cycle ( +- 0.06% ) 2,612,173,056 branches # 429.762 M/sec ( +- 0.09% ) 109,257,789 branch-misses # 4.18% of all branches ( +- 0.74% ) 6.209749362 seconds time elapsed ( +- 0.51% ) So they bring an about +5.3% improvement. Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html