primitives: Add subsidy calc benchmarks.

CalcSubsidyCacheSparse   26023311   45.99 ns/op   0 B/op   0 allocs/op
CalcWorkSubsidy          21051818   52.12 ns/op   0 B/op   0 allocs/op
CalcStakeVoteSubsidy     22216708   53.44 ns/op   0 B/op   0 allocs/op
CalcTreasurySubsidy      22610749   49.78 ns/op   0 B/op   0 allocs/op

internal/staging/primitives/subsidy_bench_test.go

@@ -0,0 +1,96 @@
+// Copyright (c) 2019-2022 The Decred developers
+// Use of this source code is governed by an ISC
+// license that can be found in the LICENSE file.
+
+package primitives
+
+import (
+	"testing"
+)
+
+// BenchmarkCalcSubsidyCacheSparse benchmarks calculating the subsidy for
+// various heights with a sparse access pattern.
+func BenchmarkCalcSubsidyCacheSparse(b *testing.B) {
+	mockParams := mockMainNetParams()
+	reductionInterval := mockParams.SubsidyReductionIntervalBlocks()
+
+	b.ResetTimer()
+	b.ReportAllocs()
+	const numIterations = 100
+	for i := 0; i < b.N; i += (numIterations * 5) {
+		cache := NewSubsidyCache(mockParams)
+		for j := int64(0); j < numIterations; j++ {
+			cache.CalcBlockSubsidy(reductionInterval * (10000 + j))
+			cache.CalcBlockSubsidy(reductionInterval * 1)
+			cache.CalcBlockSubsidy(reductionInterval * 5)
+			cache.CalcBlockSubsidy(reductionInterval * 25)
+			cache.CalcBlockSubsidy(reductionInterval * 13)
+		}
+	}
+}
+
+// BenchmarkCalcWorkSubsidy benchmarks calculating the work subsidy proportion
+// for various heights with a sparse access pattern, varying numbers of votes,
+// and with and without DCP0010 active.
+func BenchmarkCalcWorkSubsidy(b *testing.B) {
+	mockParams := mockMainNetParams()
+	reductionInterval := mockParams.SubsidyReductionIntervalBlocks()
+
+	b.ResetTimer()
+	b.ReportAllocs()
+	const numIterations = 100
+	for i := 0; i < b.N; i += (numIterations * 5) {
+		cache := NewSubsidyCache(mockParams)
+		for j := int64(0); j < numIterations; j++ {
+			cache.CalcWorkSubsidy(reductionInterval*(10000+j), 5, true)
+			cache.CalcWorkSubsidy(reductionInterval*1, 4, false)
+			cache.CalcWorkSubsidy(reductionInterval*5, 3, false)
+			cache.CalcWorkSubsidy(reductionInterval*25, 4, true)
+			cache.CalcWorkSubsidy(reductionInterval*13, 5, false)
+		}
+	}
+}
+
+// BenchmarkCalcStakeVoteSubsidy benchmarks calculating the stake vote subsidy
+// proportion for various heights with a sparse access pattern with and without
+// DCP0010 active.
+func BenchmarkCalcStakeVoteSubsidy(b *testing.B) {
+	mockParams := mockMainNetParams()
+	reductionInterval := mockParams.SubsidyReductionIntervalBlocks()
+
+	b.ResetTimer()
+	b.ReportAllocs()
+	const numIterations = 100
+	for i := 0; i < b.N; i += (numIterations * 5) {
+		cache := NewSubsidyCache(mockParams)
+		for j := int64(0); j < numIterations; j++ {
+			cache.CalcStakeVoteSubsidy(reductionInterval*(10000+j), true)
+			cache.CalcStakeVoteSubsidy(reductionInterval*1, false)
+			cache.CalcStakeVoteSubsidy(reductionInterval*5, false)
+			cache.CalcStakeVoteSubsidy(reductionInterval*25, true)
+			cache.CalcStakeVoteSubsidy(reductionInterval*13, false)
+		}
+	}
+}
+
+// BenchmarkCalcTreasurySubsidy benchmarks calculating the treasury subsidy
+// proportion for various heights with a sparse access pattern, varying numbers
+// of votes, and with and without DCP0006 active.
+func BenchmarkCalcTreasurySubsidy(b *testing.B) {
+	mockParams := mockMainNetParams()
+	reductionInterval := mockParams.SubsidyReductionIntervalBlocks()
+
+	b.ResetTimer()
+	b.ReportAllocs()
+	const numIterations = 100
+	for i := 0; i < b.N; i += (numIterations * 5) {
+		cache := NewSubsidyCache(mockParams)
+		for j := int64(0); j < numIterations; j++ {
+			cache.CalcTreasurySubsidy(reductionInterval*(10000+j), 5, true)
+			cache.CalcTreasurySubsidy(reductionInterval*1, 4, false)
+			cache.CalcTreasurySubsidy(reductionInterval*5, 3, false)
+			cache.CalcTreasurySubsidy(reductionInterval*25, 4, true)
+			cache.CalcTreasurySubsidy(reductionInterval*13, 5, true)
+		}
+	}
+}