add resease global memTree when reach a height

plugin/store/kvmvccmavl/kvmvcc_mavl.go

@@ -21,6 +21,7 @@ import (
 	drivers "github.com/33cn/chain33/system/store"
 	"github.com/33cn/chain33/types"
 	"github.com/hashicorp/golang-lru"
+	"github.com/33cn/chain33/system/store/mavl/db"
 )
 
 var (
@@ -197,6 +198,8 @@ func (kvmMavls *KVmMavlStore) MemSet(datas *types.StoreSet, sync bool) ([]byte,
 	}
 	// 删除Mavl数据
 	if datas.Height > delMavlDataHeight && !isDelMavlData && !isDelMavling() {
+		// 达到该高度时候，将全局的memTree以及tkCloseCache释放掉
+		mavl.ReleaseGlobalMem()
 		wg.Add(1)
 		go DelMavl(kvmMavls.GetDB())
 	}

vendor/github.com/33cn/chain33/system/store/mavl/db/tree.go

@@ -66,6 +66,15 @@ func EnableMemVal(enable bool) {
 	enableMemVal = enable
 }
 
+func ReleaseGlobalMem() {
+	if memTree != nil {
+		memTree = nil
+	}
+	if tkCloseCache != nil {
+		tkCloseCache = nil
+	}
+}
+
 type memNode struct {
 	data   [][]byte //顺序为lefthash, righthash, key, value
 	Height int32
@@ -542,9 +551,7 @@ func (ndb *nodeDB) SaveNode(t *Tree, node *Node) {
 }
 
 func getNodeMemTree(hash []byte) (*Node, error) {
-	if memTree == nil && tkCloseCache == nil{
-		return nil, ErrNodeNotExist
-	}
+	if memTree != nil {
 		elem, ok := memTree.Get(uintkey(farm.Hash64(hash)))
 		if ok {
 			sn := elem.(*memNode)
@@ -562,8 +569,11 @@ func getNodeMemTree(hash []byte) (*Node, error) {
 			}
 			return node, nil
 		}
+	}
+
+	if tkCloseCache != nil {
 		// 从tkCloseCache缓存中获取
-	elem, ok = tkCloseCache.Get(uintkey(farm.Hash64(hash)))
+		elem, ok := tkCloseCache.Get(uintkey(farm.Hash64(hash)))
 		if ok {
 			sn := elem.(*memNode)
 			node := &Node{
@@ -580,6 +590,7 @@ func getNodeMemTree(hash []byte) (*Node, error) {
 			}
 			return node, nil
 		}
+	}
 	return nil, ErrNodeNotExist
 }