diff --git a/server/web3bcspider/services/erc721_refresher.js b/server/web3bcspider/services/erc721_refresher.js
index 259e576..0617435 100644
--- a/server/web3bcspider/services/erc721_refresher.js
+++ b/server/web3bcspider/services/erc721_refresher.js
@@ -21,12 +21,12 @@ class Erc721Refresher extends BaseService {
   async start() {
     while (true) {
       await this.pullEvent();
-      await utils.sleep(8000 + utils.randRange(500, 1500));
+      await utils.sleep(2000 + utils.randRange(500, 1500));
     }
   }
 
   async pullEvent() {
-    const logHead = this.genLogHead() + ' pullEvent: ';
+    const logHead = this.genLogHead('pullEvent ');
   }
 
   getNetId() {
@@ -42,8 +42,8 @@ class Erc721Refresher extends BaseService {
   }
 
   genLogHead(msg) {
-    const instName = this.getNetId() + '.' + this.getContractName() + ' erc721 refresher ' + msg;
-    return instName;
+    const head = this.getNetId() + '.' + this.getContractName() + ' erc721 refresher ' + msg;
+    return head;
   }
 
 }