diff --git a/cache/include/tango_cache_client.h b/cache/include/tango_cache_client.h
index a0eda49..109c258 100644
--- a/cache/include/tango_cache_client.h
+++ b/cache/include/tango_cache_client.h
@@ -79,7 +79,7 @@ enum CACHE_HTTP_HDR_TYPE
 
 struct tango_cache_meta_get
 {
-	const char* url; //缓存:URL；非结构化日志:文件名；最大长度256字节
+	const char* url; //缓存:URL；非结构化日志:文件名；CACHE_OBJECT_KEY_HASH_SWITCH=0时最大长度256字节，=1时无限制
 	struct request_freshness get;
 };
 
diff --git a/cache/src/tango_cache_client.cpp b/cache/src/tango_cache_client.cpp
index 5a05e9a..394a7af 100644
--- a/cache/src/tango_cache_client.cpp
+++ b/cache/src/tango_cache_client.cpp
@@ -40,15 +40,18 @@ void caculate_sha256(const char *data, unsigned long len, char *result, u_int32_
 {
 	SHA256_CTX c;
 	unsigned char sha256[128];
+	u_int32_t length;
 
 	SHA256_Init(&c);
 	SHA256_Update(&c, data, len);
 	SHA256_Final(sha256, &c);
-	
-	for(u_int32_t i=0; i<32 && i<size/2; i++)
+
+	length = (size > 64)?32:(size-1)/2; //预留一个空间
+	for(u_int32_t i=0; i<length; i++)
 	{
 		sprintf(result + i*2, "%02x", sha256[i]);
 	}
+	result[length*2] = '\0';
 }
 
 static int wired_load_balancer_lookup(WLB_handle_t wiredlb, const char *key, int keylen, char *host, size_t hostsize)
@@ -300,7 +303,7 @@ int tango_cache_update_frag_evbuf(struct tango_cache_ctx *ctx, enum EVBUFFER_COP
 struct tango_cache_ctx *tango_cache_update_prepare(struct tango_cache_instance *instance, struct future* f, struct tango_cache_meta_put *meta)
 {
 	struct tango_cache_ctx *ctx;	
-	char buffer[256]={0};
+	char buffer[2064];
 	time_t expires, now, last_modify;
 
 	if((u_int64_t)instance->statistic.memory_used >= instance->cache_limit_size)
@@ -319,6 +322,9 @@ struct tango_cache_ctx *tango_cache_update_prepare(struct tango_cache_instance *
 	{
 		caculate_sha256(meta->url, strlen(meta->url), buffer, 72);
 		snprintf(ctx->object_key, 256, "%c%c/%c%c/%s", buffer[0], buffer[1], buffer[2], buffer[3], buffer+4);
+		//保存原始URL
+		snprintf(buffer, 2064, "x-amz-meta-url: %s", meta->url);
+		ctx->headers = curl_slist_append(ctx->headers, buffer);
 	}
 	else
 	{
@@ -428,7 +434,7 @@ int tango_cache_upload_once_evbuf(struct tango_cache_instance *instance, struct
 struct tango_cache_ctx *tango_cache_fetch_prepare(struct tango_cache_instance *instance, struct future* f, struct tango_cache_meta_get *meta)
 {
 	struct tango_cache_ctx *ctx;	
-	char sha256[72]={0};
+	char sha256[72];
 
 	ctx = (struct tango_cache_ctx *)calloc(1, sizeof(struct tango_cache_ctx));
 	ctx->instance = instance;
@@ -472,7 +478,7 @@ int tango_cache_fetch_object(struct tango_cache_instance *instance, struct futur
 struct tango_cache_ctx *tango_cache_delete_prepare(struct tango_cache_instance *instance, struct future* f, const char *objkey)
 {
 	struct tango_cache_ctx *ctx;	
-	char sha256[72]={0};
+	char sha256[72];
 
 	ctx = (struct tango_cache_ctx *)calloc(1, sizeof(struct tango_cache_ctx));
 	ctx->instance = instance;