diff --git a/lib_acl_cpp/changes.txt b/lib_acl_cpp/changes.txt
index 9c9b96d76..b4316d626 100644
--- a/lib_acl_cpp/changes.txt
+++ b/lib_acl_cpp/changes.txt
@@ -1,6 +1,12 @@
 修改历史列表：
 
 ------------------------------------------------------------------------
+317) 2015.6.22
+317.1) feature: dbuf_pool 类增加了 dbuf_reset 方法，可以重复使用该类对象
+317.2) performance: redis_command 类当每一个命令处理完毕后不再释放内存池对象，
+而是复用之
+317.3) bugfix: redis_zset 类有一处在调用 sizeof 时未 -1
+
 316) 2015.6.17
 316.1) feature: 增加了类 thread_queue 用来处理线程消息队列
 
diff --git a/lib_acl_cpp/include/acl_cpp/stdlib/dbuf_pool.hpp b/lib_acl_cpp/include/acl_cpp/stdlib/dbuf_pool.hpp
index 6b8bbb9db..58f53d559 100644
--- a/lib_acl_cpp/include/acl_cpp/stdlib/dbuf_pool.hpp
+++ b/lib_acl_cpp/include/acl_cpp/stdlib/dbuf_pool.hpp
@@ -17,6 +17,11 @@ public:
 	dbuf_pool(size_t block_size = 8192);
 	~dbuf_pool();
 
+	/**
+	 * 重置内存池的状态以便于重复使用该内存池对象
+	 */
+	void dbuf_reset();
+
 	/**
 	 * 分配指定长度的内存
 	 * @param len {size_t} 需要分配的内存长度，当内存比较小时(小于构造函数中的
diff --git a/lib_acl_cpp/src/redis/redis_command.cpp b/lib_acl_cpp/src/redis/redis_command.cpp
index 8a9b15ddf..b296b5e9f 100644
--- a/lib_acl_cpp/src/redis/redis_command.cpp
+++ b/lib_acl_cpp/src/redis/redis_command.cpp
@@ -113,8 +113,7 @@ void redis_command::clear(bool save_slot /* = false */)
 {
 	if (used_ > 0)
 	{
-		delete pool_;
-		pool_ = NEW dbuf_pool();
+		pool_->dbuf_reset();
 		result_ = NULL;
 	}
 	if (!save_slot)
diff --git a/lib_acl_cpp/src/redis/redis_zset.cpp b/lib_acl_cpp/src/redis/redis_zset.cpp
index f9f6805ce..d72adf431 100644
--- a/lib_acl_cpp/src/redis/redis_zset.cpp
+++ b/lib_acl_cpp/src/redis/redis_zset.cpp
@@ -1010,7 +1010,7 @@ int redis_zset::zrangebylex(const char* key, const char* min, const char* max,
 	size_t argc = 4;
 
 	argv[0] = "ZRANGEBYLEX";
-	lens[0] = sizeof("ZRANGEBYLEX");
+	lens[0] = sizeof("ZRANGEBYLEX") - 1;
 
 	argv[1] = key;
 	lens[1] = strlen(key);
diff --git a/lib_acl_cpp/src/stdlib/dbuf_pool.cpp b/lib_acl_cpp/src/stdlib/dbuf_pool.cpp
index 74e3f66ee..2f20e89a3 100644
--- a/lib_acl_cpp/src/stdlib/dbuf_pool.cpp
+++ b/lib_acl_cpp/src/stdlib/dbuf_pool.cpp
@@ -14,6 +14,11 @@ dbuf_pool::~dbuf_pool()
 	acl_dbuf_pool_destroy(pool_);
 }
 
+void dbuf_pool::dbuf_reset()
+{
+	acl_dbuf_pool_reset(pool_);
+}
+
 void* dbuf_pool::dbuf_alloc(size_t len)
 {
 	return acl_dbuf_pool_alloc(pool_, len);