add more info

session-dealer/mysql/model.go

@@ -1,5 +1,9 @@
 package mysql
 
+import (
+	log "github.com/sirupsen/logrus"
+)
+
 type handshakeResponse41 struct {
 	Capability uint32
 	Collation  uint8
@@ -13,3 +17,47 @@ type jigsaw struct {
 	b int64
 	e int64
 }
+
+type packageWindowCounter struct {
+	sizeCount map[int]int64
+	visitCount int64
+	suggestSize int
+}
+
+func newPackageWindowCounter() *packageWindowCounter {
+	return &packageWindowCounter{
+		sizeCount: make(map[int]int64, 4),
+		suggestSize: 512,
+	}
+}
+
+func (pwc *packageWindowCounter) refresh (readSize int, isLastPackage bool)  {
+	if pwc.visitCount > 10000 {
+		return
+	}
+
+	log.Debugf("WindowCounter: %#v", pwc.sizeCount)
+	pwc.visitCount += 1
+	miniMatchSize := maxIPPackageSize
+	for size := range pwc.sizeCount  {
+		if readSize % size == 0 && miniMatchSize > size {
+			miniMatchSize = size
+		}
+	}
+	if miniMatchSize < maxIPPackageSize {
+		pwc.sizeCount[miniMatchSize] = pwc.sizeCount[miniMatchSize] + 1
+	} else if !isLastPackage {
+		pwc.sizeCount[readSize] = 1
+	}
+
+	mostFrequentSize := pwc.suggestSize
+	mostFrequentCount := int64(0)
+	for size, count := range pwc.sizeCount  {
+		if count > mostFrequentCount {
+			mostFrequentSize = size
+			mostFrequentCount = count
+		}
+	}
+
+	pwc.suggestSize = mostFrequentSize
+}