bmbm
- 1_8_6_287
- 1_8_7_72
- 1_8_7_330
- 1_9_1_378 (0)
- 1_9_2_180 (0)
- 1_9_3_125 (0)
- 1_9_3_392 (0)
- 2_1_10 (-38)
- 2_2_9 (0)
- 2_4_6 (0)
- 2_5_5 (0)
- 2_6_3 (0)
- What's this?
bmbm(width = 0)
public
Sometimes benchmark results are skewed because code executed earlier encounters different garbage collection overheads than that run later. #bmbm attempts to minimize this effect by running the tests twice, the first time as a rehearsal in order to get the runtime environment stable, the second time for real. GC.start is executed before the start of each of the real timings; the cost of this is not included in the timings. In reality, though, there’s only so much that #bmbm can do, and the results are not guaranteed to be isolated from garbage collection and other effects.
Because #bmbm takes two passes through the tests, it can calculate the required label width.
require 'benchmark' array = (1..1000000).map { rand } Benchmark.bmbm do |x| x.report("sort!") { array.dup.sort! } x.report("sort") { array.dup.sort } end
Generates:
Rehearsal ----------------------------------------- sort! 1.440000 0.010000 1.450000 ( 1.446833) sort 1.440000 0.000000 1.440000 ( 1.448257) -------------------------------- total: 2.890000sec user system total real sort! 1.460000 0.000000 1.460000 ( 1.458065) sort 1.450000 0.000000 1.450000 ( 1.455963)
#bmbm yields a Benchmark::Job object and returns an array of Benchmark::Tms objects.