38 lines
1.1 KiB
Go
38 lines
1.1 KiB
Go
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// Copyright 2014 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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/*
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The benchcmp command displays performance changes between benchmarks.
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Benchcmp parses the output of two 'go test' benchmark runs,
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correlates the results per benchmark, and displays the deltas.
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To measure the performance impact of a change, use 'go test'
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to run benchmarks before and after the change:
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go test -run=NONE -bench=. ./... > old.txt
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# make changes
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go test -run=NONE -bench=. ./... > new.txt
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Then feed the benchmark results to benchcmp:
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benchcmp old.txt new.txt
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Benchcmp will summarize and display the performance changes,
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in a format like this:
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$ benchcmp old.txt new.txt
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benchmark old ns/op new ns/op delta
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BenchmarkConcat 523 68.6 -86.88%
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benchmark old allocs new allocs delta
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BenchmarkConcat 3 1 -66.67%
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benchmark old bytes new bytes delta
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BenchmarkConcat 80 48 -40.00%
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*/
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package main // import "golang.org/x/tools/cmd/benchcmp"
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