Changes on QC

Summary:
removed KV_Btree_Array.cpp
removed query_SQL from MySQL_Data_Stream
added some documentation for QC_entry_t
Query_Cache::get() and Query_Cache::set() now requires also the length of the key
Query_Cache::get() and Query_Cache::set() now process hk (the hash key) using the length of the key

Query Cache enhancement on user/schema

Query Cache now supports distinct entries based on user/schema .
This is achieved passing to Query_Cache::set() and Query_Cache::get() the hash that identifies user and schema

Test Plan: None

Reviewers: rene

Differential Revision: http://phab.sysown.com/D3

include/query_cache.hpp

@@ -72,8 +72,8 @@ class Query_Cache {
 	Query_Cache();
 	~Query_Cache();
 	void print_version();
-	bool set(const unsigned char *, uint32_t, unsigned char *, uint32_t, time_t);
-	unsigned char * get(const unsigned char *, const uint32_t, uint32_t *);
+	bool set(uint64_t , const unsigned char *, uint32_t, unsigned char *, uint32_t, time_t);
+	unsigned char * get(uint64_t , const unsigned char *, const uint32_t, uint32_t *);
 	uint64_t flush();
 };
 #endif /* __CLASS_QUERY_CACHE_H */

lib/MySQL_Session.cpp

@@ -1641,7 +1641,7 @@ bool MySQL_Session::handler___status_WAITING_CLIENT_DATA___STATE_SLEEP___MYSQL_C
 //		memcpy(client_myds->query_SQL,(unsigned char *)pkt->ptr+sizeof(mysql_hdr)+1,pkt->size-sizeof(mysql_hdr)-1);
 //		client_myds->query_SQL[pkt->size-sizeof(mysql_hdr)-1]=0;
 		uint32_t resbuf=0;
-		unsigned char *aa=GloQC->get((const unsigned char *)client_myds->mysql_real_query.QueryPtr , client_myds->mysql_real_query.QuerySize , &resbuf);
+		unsigned char *aa=GloQC->get( client_myds->myconn->userinfo->hash, (const unsigned char *)client_myds->mysql_real_query.QueryPtr , client_myds->mysql_real_query.QuerySize , &resbuf);
 		if (aa) {
 			l_free(pkt->size,pkt->ptr);
 //			l_free(strlen((char *)client_myds->query_SQL)+1,client_myds->query_SQL);
@@ -1798,7 +1798,7 @@ void MySQL_Session::MySQL_Result_to_MySQL_wire(MYSQL *mysql, MySQL_ResultSet *My
 					client_myds->resultset_length=MyRS->resultset_size;
 					unsigned char *aa=client_myds->resultset2buffer(false);
 					while (client_myds->resultset->len) client_myds->resultset->remove_index(client_myds->resultset->len-1,NULL);
-					GloQC->set((const unsigned char *)client_myds->mysql_real_query.QueryPtr , client_myds->mysql_real_query.QuerySize , aa,client_myds->resultset_length,qpo->cache_ttl);
+					GloQC->set( client_myds->myconn->userinfo->hash , (const unsigned char *)client_myds->mysql_real_query.QueryPtr , client_myds->mysql_real_query.QuerySize , aa,client_myds->resultset_length,qpo->cache_ttl);
 					l_free(client_myds->resultset_length,aa);
 					client_myds->resultset_length=0;
 //					l_free(strlen((char *)client_myds->query_SQL)+1,client_myds->query_SQL);

lib/Query_Cache.cpp

@@ -259,10 +259,10 @@ Query_Cache::~Query_Cache() {
 
 
 
-unsigned char * Query_Cache::get(const unsigned char *kp, const uint32_t kl, uint32_t *lv) {
+unsigned char * Query_Cache::get(uint64_t user_hash, const unsigned char *kp, const uint32_t kl, uint32_t *lv) {
 	unsigned char *result=NULL;
 
-	uint64_t hk=SpookyHash::Hash64(kp, kl,0);
+	uint64_t hk=SpookyHash::Hash64(kp, kl, user_hash);
 	unsigned char i=hk%SHARED_QUERY_CACHE_HASH_TABLES;
 
 	QC_entry_t *entry=KVs[i].lookup(hk);
@@ -280,7 +280,7 @@ unsigned char * Query_Cache::get(const unsigned char *kp, const uint32_t kl, uin
 	return result;
 }
 
-bool Query_Cache::set(const unsigned char *kp, uint32_t kl, unsigned char *vp, uint32_t vl, time_t expire) {
+bool Query_Cache::set(uint64_t user_hash, const unsigned char *kp, uint32_t kl, unsigned char *vp, uint32_t vl, time_t expire) {
 	QC_entry_t *entry = (QC_entry_t *)malloc(sizeof(QC_entry_t));
 	entry->klen=kl;
 	entry->length=vl;
@@ -295,7 +295,7 @@ bool Query_Cache::set(const unsigned char *kp, uint32_t kl, unsigned char *vp, u
 	} else {
 		entry->expire=QCnow+expire; // expire is seconds
 	}
-	uint64_t hk=SpookyHash::Hash64(kp, kl, 0);
+	uint64_t hk=SpookyHash::Hash64(kp, kl, user_hash);
 	unsigned char i=hk%SHARED_QUERY_CACHE_HASH_TABLES;
 	entry->key=hk;
 	KVs[i].replace(hk, entry);