--- /dev/null
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "fmt"
+ "math"
+
+ "golang.org/x/tools/benchmark/parse"
+)
+
+// BenchCmp is a pair of benchmarks.
+type BenchCmp struct {
+ Before *parse.Benchmark
+ After *parse.Benchmark
+}
+
+// Correlate correlates benchmarks from two BenchSets.
+func Correlate(before, after parse.Set) (cmps []BenchCmp, warnings []string) {
+ cmps = make([]BenchCmp, 0, len(after))
+ for name, beforebb := range before {
+ afterbb := after[name]
+ if len(beforebb) != len(afterbb) {
+ warnings = append(warnings, fmt.Sprintf("ignoring %s: before has %d instances, after has %d", name, len(beforebb), len(afterbb)))
+ continue
+ }
+ for i, beforeb := range beforebb {
+ afterb := afterbb[i]
+ cmps = append(cmps, BenchCmp{beforeb, afterb})
+ }
+ }
+ return
+}
+
+func (c BenchCmp) Name() string { return c.Before.Name }
+func (c BenchCmp) String() string { return fmt.Sprintf("<%s, %s>", c.Before, c.After) }
+func (c BenchCmp) Measured(flag int) bool { return (c.Before.Measured & c.After.Measured & flag) != 0 }
+func (c BenchCmp) DeltaNsPerOp() Delta { return Delta{c.Before.NsPerOp, c.After.NsPerOp} }
+func (c BenchCmp) DeltaMBPerS() Delta { return Delta{c.Before.MBPerS, c.After.MBPerS} }
+func (c BenchCmp) DeltaAllocedBytesPerOp() Delta {
+ return Delta{float64(c.Before.AllocedBytesPerOp), float64(c.After.AllocedBytesPerOp)}
+}
+func (c BenchCmp) DeltaAllocsPerOp() Delta {
+ return Delta{float64(c.Before.AllocsPerOp), float64(c.After.AllocsPerOp)}
+}
+
+// Delta is the before and after value for a benchmark measurement.
+// Both must be non-negative.
+type Delta struct {
+ Before float64
+ After float64
+}
+
+// mag calculates the magnitude of a change, regardless of the direction of
+// the change. mag is intended for sorting and has no independent meaning.
+func (d Delta) mag() float64 {
+ switch {
+ case d.Before != 0 && d.After != 0 && d.Before >= d.After:
+ return d.After / d.Before
+ case d.Before != 0 && d.After != 0 && d.Before < d.After:
+ return d.Before / d.After
+ case d.Before == 0 && d.After == 0:
+ return 1
+ default:
+ // 0 -> 1 or 1 -> 0
+ // These are significant changes and worth surfacing.
+ return math.Inf(1)
+ }
+}
+
+// Changed reports whether the benchmark quantities are different.
+func (d Delta) Changed() bool { return d.Before != d.After }
+
+// Float64 returns After / Before. If Before is 0, Float64 returns
+// 1 if After is also 0, and +Inf otherwise.
+func (d Delta) Float64() float64 {
+ switch {
+ case d.Before != 0:
+ return d.After / d.Before
+ case d.After == 0:
+ return 1
+ default:
+ return math.Inf(1)
+ }
+}
+
+// Percent formats a Delta as a percent change, ranging from -100% up.
+func (d Delta) Percent() string {
+ return fmt.Sprintf("%+.2f%%", 100*d.Float64()-100)
+}
+
+// Multiple formats a Delta as a multiplier, ranging from 0.00x up.
+func (d Delta) Multiple() string {
+ return fmt.Sprintf("%.2fx", d.Float64())
+}
+
+func (d Delta) String() string {
+ return fmt.Sprintf("Δ(%f, %f)", d.Before, d.After)
+}
+
+// ByParseOrder sorts BenchCmps to match the order in
+// which the Before benchmarks were presented to Parse.
+type ByParseOrder []BenchCmp
+
+func (x ByParseOrder) Len() int { return len(x) }
+func (x ByParseOrder) Swap(i, j int) { x[i], x[j] = x[j], x[i] }
+func (x ByParseOrder) Less(i, j int) bool { return x[i].Before.Ord < x[j].Before.Ord }
+
+// lessByDelta provides lexicographic ordering:
+// * largest delta by magnitude
+// * alphabetic by name
+func lessByDelta(i, j BenchCmp, calcDelta func(BenchCmp) Delta) bool {
+ iDelta, jDelta := calcDelta(i).mag(), calcDelta(j).mag()
+ if iDelta != jDelta {
+ return iDelta < jDelta
+ }
+ return i.Name() < j.Name()
+}
+
+// ByDeltaNsPerOp sorts BenchCmps lexicographically by change
+// in ns/op, descending, then by benchmark name.
+type ByDeltaNsPerOp []BenchCmp
+
+func (x ByDeltaNsPerOp) Len() int { return len(x) }
+func (x ByDeltaNsPerOp) Swap(i, j int) { x[i], x[j] = x[j], x[i] }
+func (x ByDeltaNsPerOp) Less(i, j int) bool { return lessByDelta(x[i], x[j], BenchCmp.DeltaNsPerOp) }
+
+// ByDeltaMBPerS sorts BenchCmps lexicographically by change
+// in MB/s, descending, then by benchmark name.
+type ByDeltaMBPerS []BenchCmp
+
+func (x ByDeltaMBPerS) Len() int { return len(x) }
+func (x ByDeltaMBPerS) Swap(i, j int) { x[i], x[j] = x[j], x[i] }
+func (x ByDeltaMBPerS) Less(i, j int) bool { return lessByDelta(x[i], x[j], BenchCmp.DeltaMBPerS) }
+
+// ByDeltaAllocedBytesPerOp sorts BenchCmps lexicographically by change
+// in B/op, descending, then by benchmark name.
+type ByDeltaAllocedBytesPerOp []BenchCmp
+
+func (x ByDeltaAllocedBytesPerOp) Len() int { return len(x) }
+func (x ByDeltaAllocedBytesPerOp) Swap(i, j int) { x[i], x[j] = x[j], x[i] }
+func (x ByDeltaAllocedBytesPerOp) Less(i, j int) bool {
+ return lessByDelta(x[i], x[j], BenchCmp.DeltaAllocedBytesPerOp)
+}
+
+// ByDeltaAllocsPerOp sorts BenchCmps lexicographically by change
+// in allocs/op, descending, then by benchmark name.
+type ByDeltaAllocsPerOp []BenchCmp
+
+func (x ByDeltaAllocsPerOp) Len() int { return len(x) }
+func (x ByDeltaAllocsPerOp) Swap(i, j int) { x[i], x[j] = x[j], x[i] }
+func (x ByDeltaAllocsPerOp) Less(i, j int) bool {
+ return lessByDelta(x[i], x[j], BenchCmp.DeltaAllocsPerOp)
+}
projects / dotfiles / .git / blobdiff