From 15c66abbe0cb05f187b71b607c38d0075a162e86 Mon Sep 17 00:00:00 2001
From: Aliaksandr Valialkin <valyala@victoriametrics.com>
Date: Wed, 15 May 2024 16:40:32 +0200
Subject: [PATCH] wip

---
 lib/logstorage/bitmap_timing_test.go | 82 ++++++++++++++++++++++++++++
 1 file changed, 82 insertions(+)
 create mode 100644 lib/logstorage/bitmap_timing_test.go

diff --git a/lib/logstorage/bitmap_timing_test.go b/lib/logstorage/bitmap_timing_test.go
new file mode 100644
index 000000000..6bbcc8c8a
--- /dev/null
+++ b/lib/logstorage/bitmap_timing_test.go
@@ -0,0 +1,82 @@
+package logstorage
+
+import (
+	"testing"
+)
+
+func BenchmarkBitmapForEachSetBit(b *testing.B) {
+	const bitsLen = 64*1024
+
+	b.Run("no-zero-bits-noclear", func(b *testing.B) {
+		bm := getBitmap(bitsLen)
+		bm.setBits()
+		benchmarkBitmapForEachSetBit(b, bm, false)
+		putBitmap(bm)
+	})
+	b.Run("no-zero-bits-clear", func(b *testing.B) {
+		bm := getBitmap(bitsLen)
+		bm.setBits()
+		benchmarkBitmapForEachSetBit(b, bm, true)
+		putBitmap(bm)
+	})
+	b.Run("half-zero-bits-noclear", func(b *testing.B) {
+		bm := getBitmap(bitsLen)
+		bm.setBits()
+		bm.forEachSetBit(func(idx int) bool {
+			return idx%2 == 0
+		})
+		benchmarkBitmapForEachSetBit(b, bm, false)
+		putBitmap(bm)
+	})
+	b.Run("half-zero-bits-clear", func(b *testing.B) {
+		bm := getBitmap(bitsLen)
+		bm.setBits()
+		bm.forEachSetBit(func(idx int) bool {
+			return idx%2 == 0
+		})
+		benchmarkBitmapForEachSetBit(b, bm, true)
+		putBitmap(bm)
+	})
+	b.Run("one-set-bit-noclear", func(b *testing.B) {
+		bm := getBitmap(bitsLen)
+		bm.setBits()
+		bm.forEachSetBit(func(idx int) bool {
+			return idx == bitsLen/2
+		})
+		benchmarkBitmapForEachSetBit(b, bm, false)
+		putBitmap(bm)
+	})
+	b.Run("one-set-bit-clear", func(b *testing.B) {
+		bm := getBitmap(bitsLen)
+		bm.setBits()
+		bm.forEachSetBit(func(idx int) bool {
+			return idx == bitsLen/2
+		})
+		benchmarkBitmapForEachSetBit(b, bm, true)
+		putBitmap(bm)
+	})
+}
+
+func benchmarkBitmapForEachSetBit(b *testing.B, bm *bitmap, isClearBits bool) {
+	b.SetBytes(int64(bm.bitsLen))
+	b.ReportAllocs()
+	b.RunParallel(func(pb *testing.PB) {
+		bmLocal := getBitmap(bm.bitsLen)
+		for pb.Next() {
+			bmLocal.copyFrom(bm)
+			bmLocal.forEachSetBit(func(idx int) bool {
+				return !isClearBits
+			})
+			if isClearBits {
+				if !bmLocal.isZero() {
+					panic("BUG: bitmap must have no set bits")
+				}
+			} else {
+				if bmLocal.isZero() {
+					panic("BUG: bitmap must have some set bits")
+				}
+			}
+		}
+		putBitmap(bmLocal)
+	})
+}