github.com/april1989/origin-go-tools@v0.0.32/cmd/benchcmp/doc.go (about)

     1  // Copyright 2014 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  /*
     6  
     7  The benchcmp command displays performance changes between benchmarks.
     8  
     9  Benchcmp parses the output of two 'go test' benchmark runs,
    10  correlates the results per benchmark, and displays the deltas.
    11  
    12  To measure the performance impact of a change, use 'go test'
    13  to run benchmarks before and after the change:
    14  
    15  	go test -run=NONE -bench=. ./... > old.txt
    16  	# make changes
    17  	go test -run=NONE -bench=. ./... > new.txt
    18  
    19  Then feed the benchmark results to benchcmp:
    20  
    21  	benchcmp old.txt new.txt
    22  
    23  Benchcmp will summarize and display the performance changes,
    24  in a format like this:
    25  
    26  	$ benchcmp old.txt new.txt
    27  	benchmark           old ns/op     new ns/op     delta
    28  	BenchmarkConcat     523           68.6          -86.88%
    29  
    30  	benchmark           old allocs     new allocs     delta
    31  	BenchmarkConcat     3              1              -66.67%
    32  
    33  	benchmark           old bytes     new bytes     delta
    34  	BenchmarkConcat     80            48            -40.00%
    35  
    36  */
    37  package main // import "github.com/april1989/origin-go-tools/cmd/benchcmp"