1// Copyright 2022 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 5package benchmarks 6 7import ( 8 "context" 9 "flag" 10 "internal/race" 11 "io" 12 "log/slog" 13 "log/slog/internal" 14 "testing" 15) 16 17func init() { 18 flag.BoolVar(&internal.IgnorePC, "nopc", false, "do not invoke runtime.Callers") 19} 20 21// We pass Attrs inline because it affects allocations: building 22// up a list outside of the benchmarked code and passing it in with "..." 23// reduces measured allocations. 24 25func BenchmarkAttrs(b *testing.B) { 26 ctx := context.Background() 27 for _, handler := range []struct { 28 name string 29 h slog.Handler 30 skipRace bool 31 }{ 32 {"disabled", disabledHandler{}, false}, 33 {"async discard", newAsyncHandler(), true}, 34 {"fastText discard", newFastTextHandler(io.Discard), false}, 35 {"Text discard", slog.NewTextHandler(io.Discard, nil), false}, 36 {"JSON discard", slog.NewJSONHandler(io.Discard, nil), false}, 37 } { 38 logger := slog.New(handler.h) 39 b.Run(handler.name, func(b *testing.B) { 40 if handler.skipRace && race.Enabled { 41 b.Skip("skipping benchmark in race mode") 42 } 43 for _, call := range []struct { 44 name string 45 f func() 46 }{ 47 { 48 // The number should match nAttrsInline in slog/record.go. 49 // This should exercise the code path where no allocations 50 // happen in Record or Attr. If there are allocations, they 51 // should only be from Duration.String and Time.String. 52 "5 args", 53 func() { 54 logger.LogAttrs(nil, slog.LevelInfo, testMessage, 55 slog.String("string", testString), 56 slog.Int("status", testInt), 57 slog.Duration("duration", testDuration), 58 slog.Time("time", testTime), 59 slog.Any("error", testError), 60 ) 61 }, 62 }, 63 { 64 "5 args ctx", 65 func() { 66 logger.LogAttrs(ctx, slog.LevelInfo, testMessage, 67 slog.String("string", testString), 68 slog.Int("status", testInt), 69 slog.Duration("duration", testDuration), 70 slog.Time("time", testTime), 71 slog.Any("error", testError), 72 ) 73 }, 74 }, 75 { 76 "10 args", 77 func() { 78 logger.LogAttrs(nil, slog.LevelInfo, testMessage, 79 slog.String("string", testString), 80 slog.Int("status", testInt), 81 slog.Duration("duration", testDuration), 82 slog.Time("time", testTime), 83 slog.Any("error", testError), 84 slog.String("string", testString), 85 slog.Int("status", testInt), 86 slog.Duration("duration", testDuration), 87 slog.Time("time", testTime), 88 slog.Any("error", testError), 89 ) 90 }, 91 }, 92 { 93 // Try an extreme value to see if the results are reasonable. 94 "40 args", 95 func() { 96 logger.LogAttrs(nil, slog.LevelInfo, testMessage, 97 slog.String("string", testString), 98 slog.Int("status", testInt), 99 slog.Duration("duration", testDuration), 100 slog.Time("time", testTime), 101 slog.Any("error", testError), 102 slog.String("string", testString), 103 slog.Int("status", testInt), 104 slog.Duration("duration", testDuration), 105 slog.Time("time", testTime), 106 slog.Any("error", testError), 107 slog.String("string", testString), 108 slog.Int("status", testInt), 109 slog.Duration("duration", testDuration), 110 slog.Time("time", testTime), 111 slog.Any("error", testError), 112 slog.String("string", testString), 113 slog.Int("status", testInt), 114 slog.Duration("duration", testDuration), 115 slog.Time("time", testTime), 116 slog.Any("error", testError), 117 slog.String("string", testString), 118 slog.Int("status", testInt), 119 slog.Duration("duration", testDuration), 120 slog.Time("time", testTime), 121 slog.Any("error", testError), 122 slog.String("string", testString), 123 slog.Int("status", testInt), 124 slog.Duration("duration", testDuration), 125 slog.Time("time", testTime), 126 slog.Any("error", testError), 127 slog.String("string", testString), 128 slog.Int("status", testInt), 129 slog.Duration("duration", testDuration), 130 slog.Time("time", testTime), 131 slog.Any("error", testError), 132 slog.String("string", testString), 133 slog.Int("status", testInt), 134 slog.Duration("duration", testDuration), 135 slog.Time("time", testTime), 136 slog.Any("error", testError), 137 ) 138 }, 139 }, 140 } { 141 b.Run(call.name, func(b *testing.B) { 142 b.ReportAllocs() 143 b.RunParallel(func(pb *testing.PB) { 144 for pb.Next() { 145 call.f() 146 } 147 }) 148 }) 149 } 150 }) 151 } 152} 153