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erigontech · Nov 5, 2024 · 61e3a99 · 61e3a99
1 parent 6a1d322
commit 61e3a99
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Showing 3 changed files with 38 additions and 28 deletions.
diff --git a/erigon-lib/seg/decompress.go b/erigon-lib/seg/decompress.go
@@ -1066,31 +1066,27 @@ func (g *Getter) FastNext(buf []byte) ([]byte, uint64) {
 	return buf[:wordLen], postLoopPos
 }
 
-// BinarySearch - !expecting sorted file
-func (g *Getter) BinarySearch(fromPrefix []byte, count int, f func(i uint64) (offset uint64)) (value []byte, ok bool) {
+// BinarySearch - !expecting sorted file - does Seek `g` to key which >= `fromPrefix` by using BinarySearch - means unoptimal and touching many places in file
+// use `.Next` to read found
+// at `ok = false` leaving `g` in unpredictible state
+func (g *Getter) BinarySearch(seek []byte, count int, getOffset func(i uint64) (offset uint64)) (foundOffset uint64, ok bool) {
+	var key []byte
 	foundItem := sort.Search(count, func(i int) bool {
-		offset := f(uint64(i))
+		offset := getOffset(uint64(i))
 		g.Reset(offset)
 		if g.HasNext() {
-			key, _ := g.Next(nil)
-			return bytes.Compare(key, fromPrefix) >= 0
+			key, _ = g.Next(key[:0])
+			return bytes.Compare(key, seek) >= 0
 		}
 		return false
 	})
 	if foundItem == count { // `Search` returns `n` if not found
-		return nil, false
+		return 0, false
 	}
-	foundOffset := f(uint64(foundItem))
+	foundOffset = getOffset(uint64(foundItem))
 	g.Reset(foundOffset)
-	if g.HasNext() {
-		value, _ = g.Next(nil)
-	}
-	if dbg.AssertEnabled && foundItem > 2 {
-		g.Reset(f(uint64(foundItem - 2))) // prev key
-		prevKey, _ := g.Next(nil)
-		if bytes.Compare(prevKey, fromPrefix) >= 0 {
-			panic(fmt.Errorf("see smaller key: fromPrefix=%x, prevKey=%x", fromPrefix, prevKey))
-		}
+	if !g.HasNext() {
+		return 0, false
 	}
-	return value, true
+	return foundOffset, true
 }
diff --git a/erigon-lib/seg/decompress_test.go b/erigon-lib/seg/decompress_test.go
@@ -297,33 +297,43 @@ func TestUncompressed(t *testing.T) {
 		offsets = append(offsets, offset)
 	}
 
-	t.Run("BinarySearch", func(t *testing.T) {
+	t.Run("BinarySearch middle", func(t *testing.T) {
 		require := require.New(t)
-		k, ok := g.BinarySearch([]byte("ipsum"), d.Count(), func(i uint64) (offset uint64) { return offsets[i] })
+		_, ok := g.BinarySearch([]byte("ipsum"), d.Count(), func(i uint64) (offset uint64) { return offsets[i] })
 		require.True(ok)
+		k, _ := g.Next(nil)
 		require.Equal("ipsum 38", string(k))
-		k, ok = g.BinarySearch([]byte("ipsu"), d.Count(), func(i uint64) (offset uint64) { return offsets[i] })
+		_, ok = g.BinarySearch([]byte("ipsu"), d.Count(), func(i uint64) (offset uint64) { return offsets[i] })
 		require.True(ok)
+		k, _ = g.Next(nil)
 		require.Equal("ipsum 38", string(k))
-
+	})
+	t.Run("BinarySearch end of file", func(t *testing.T) {
+		require := require.New(t)
 		//last word is `voluptate`
-		k, ok = g.BinarySearch([]byte("voluptate"), d.Count(), func(i uint64) (offset uint64) { return offsets[i] })
+		_, ok := g.BinarySearch([]byte("voluptate"), d.Count(), func(i uint64) (offset uint64) { return offsets[i] })
 		require.True(ok)
+		k, _ := g.Next(nil)
 		require.Equal("voluptate 69", string(k))
-		k, ok = g.BinarySearch([]byte("voluptat"), d.Count(), func(i uint64) (offset uint64) { return offsets[i] })
+		_, ok = g.BinarySearch([]byte("voluptat"), d.Count(), func(i uint64) (offset uint64) { return offsets[i] })
 		require.True(ok)
+		k, _ = g.Next(nil)
 		require.Equal("voluptate 69", string(k))
-		k, ok = g.BinarySearch([]byte("voluptatez"), d.Count(), func(i uint64) (offset uint64) { return offsets[i] })
+		_, ok = g.BinarySearch([]byte("voluptatez"), d.Count(), func(i uint64) (offset uint64) { return offsets[i] })
 		require.False(ok)
-		require.Equal("", string(k))
+	})
 
+	t.Run("BinarySearch begin of file", func(t *testing.T) {
+		require := require.New(t)
 		//first word is ``
-		k, ok = g.BinarySearch([]byte(""), d.Count(), func(i uint64) (offset uint64) { return offsets[i] })
+		_, ok := g.BinarySearch([]byte(""), d.Count(), func(i uint64) (offset uint64) { return offsets[i] })
 		require.True(ok)
+		k, _ := g.Next(nil)
 		require.Equal("", string(k))
 
-		k, ok = g.BinarySearch(nil, d.Count(), func(i uint64) (offset uint64) { return offsets[i] })
+		_, ok = g.BinarySearch(nil, d.Count(), func(i uint64) (offset uint64) { return offsets[i] })
 		require.True(ok)
+		k, _ = g.Next(nil)
 		require.Equal("", string(k))
 	})
 

diff --git a/erigon-lib/state/history.go b/erigon-lib/state/history.go
@@ -1365,7 +1365,11 @@ func (ht *HistoryRoTx) WalkAsOf(ctx context.Context, startTxNum uint64, from, to
 		var offset uint64
 		if len(from) > 0 {
 			n := item.src.decompressor.Count() / 2
-			offset = g.BinarySearch(from, n, idx.OrdinalLookup)
+			var ok bool
+			offset, ok = g.BinarySearch(from, n, idx.OrdinalLookup)
+			if !ok {
+				offset = 0
+			}
 		}
 		g.Reset(offset)
 		if g.HasNext() {