diff --git a/db/db_impl.cc b/db/db_impl.cc
index d9af970..6402fc0 100644
--- a/db/db_impl.cc
+++ b/db/db_impl.cc
@@ -1963,9 +1963,10 @@ void DBImpl::GarbageCollect() {
       status = Put(write_op, key, value);
 
       mutex_.Lock();
-      valuelog_finding_key="";
-      mutex_.Unlock();
+      valuelog_finding_key=Slice();
       lock_valuelog_key_mutex_cond_.SignalAll();
+      mutex_.Unlock();
+      
 
       if (!status.ok()) {
         std::cerr << "Error accessing sstable: " << status.ToString()
diff --git a/db/write_batch.cc b/db/write_batch.cc
index 74a4773..0757c39 100644
--- a/db/write_batch.cc
+++ b/db/write_batch.cc
@@ -131,8 +131,8 @@ class ValueLogInserter : public WriteBatch::Handler {
   public:
   WriteBatch writeBatch_;
   DB* db_;
-  ValueLogInserter(WriteBatch writeBatch,DB* db){
-    writeBatch_=writeBatch;
+  std::vector<std::pair<Slice,Slice>> kvs;
+  ValueLogInserter(DB* db){
     db_=db;
   }
 
@@ -142,22 +142,28 @@ class ValueLogInserter : public WriteBatch::Handler {
     if(value.size()<100){
       buf+=(char)(0x00);// should set in key
       buf.append(value.data(),value.size());
+      writeBatch_.Put(key,Slice(buf));
     }
     else{
-      buf+=(char)(0x01);
-      std::vector<std::pair<Slice,Slice>> kv;
-      kv.push_back({key,value});
-      auto res=db_->WriteValueLog(kv);
-      PutVarint64(&buf,res[0].first);
-      PutVarint64(&buf,res[0].second);
+      kvs.push_back({key,value});
     }
-    new_value=Slice(buf);
-    writeBatch_.Put(key,new_value);  
   }
   
   void Delete(const Slice& key) override {
     writeBatch_.Delete(key);
   }
+
+  void batch_insert(){
+    if(kvs.size()==0)return;
+    auto kv_res=db_->WriteValueLog(kvs);
+    for(int i=0;i<kvs.size();i++){
+      std::string buf;
+      buf+=(char)(0x01);
+      PutVarint64(&buf,kv_res[i].first);
+      PutVarint64(&buf,kv_res[i].second);
+      writeBatch_.Put(kvs[i].first,Slice(buf));
+    }
+  }
 };
 
 class ValueLogChecker : public WriteBatch::Handler {
@@ -186,14 +192,15 @@ class ValueLogChecker : public WriteBatch::Handler {
     int l=0;
     int r=len-1;
     bool locked=false;
-    while(1){
+    while(!lock_key_->empty()){
       locked=false;
-      while(keys[l]==*lock_key_){
+      while(!lock_key_->empty()&&keys[l]==*lock_key_){
         cond_var_->Wait();
         locked=true;
       }
       if(locked){
-        r=l;//a full round to make sure no key = current lock_key
+        r=l-1;//a full round to make sure no key = current lock_key
+        if(r<0)r=len-1;
       }
       else if(l==r)break;
       if(++l==len)l=0;
@@ -215,15 +222,17 @@ Status WriteBatchInternal::InsertInto(const WriteBatch* b, MemTable* memtable) {
 Status WriteBatchInternal::checkValueLog(WriteBatch* b,DB* db_,Slice* lock_key,port::CondVar* cond_var_){
   if(lock_key->size()>0){
     ValueLogChecker checker(db_,lock_key,cond_var_);
-    b->Iterate(&checker);
+    auto res=b->Iterate(&checker);
+    if(!res.ok())return res;
     checker.CheckValid();
   }
   return Status::OK();
 }
 
 Status WriteBatchInternal::ConverToValueLog(WriteBatch* b,DB* db_){
-  ValueLogInserter inserter(WriteBatch(),db_);
+  ValueLogInserter inserter(db_);
   auto res=b->Iterate(&inserter);
+  inserter.batch_insert();
   *b=inserter.writeBatch_;
   return res;
 }