Reverting patch for bug30087

mysql-test/r/query_cache.result

@@ -566,7 +566,7 @@ select * from t1;
 a
 set GLOBAL query_cache_size=1024;
 Warnings:
-Warning	1282	Query cache failed to set size 1024 (minimal value: 41297); new query cache size is 0
+Warning	1282	Query cache failed to set size 1024; new query cache size is 0
 show global variables like "query_cache_size";
 Variable_name	Value
 query_cache_size	0
@@ -574,7 +574,7 @@ select * from t1;
 a
 set GLOBAL query_cache_size=10240;
 Warnings:
-Warning	1282	Query cache failed to set size 10240 (minimal value: 41297); new query cache size is 0
+Warning	1282	Query cache failed to set size 10240; new query cache size is 0
 show global variables like "query_cache_size";
 Variable_name	Value
 query_cache_size	0
@@ -582,7 +582,7 @@ select * from t1;
 a
 set GLOBAL query_cache_size=20480;
 Warnings:
-Warning	1282	Query cache failed to set size 20480 (minimal value: 41297); new query cache size is 0
+Warning	1282	Query cache failed to set size 20480; new query cache size is 0
 show global variables like "query_cache_size";
 Variable_name	Value
 query_cache_size	0
@@ -590,7 +590,7 @@ select * from t1;
 a
 set GLOBAL query_cache_size=40960;
 Warnings:
-Warning	1282	Query cache failed to set size 40960 (minimal value: 41297); new query cache size is 0
+Warning	1282	Query cache failed to set size 40960; new query cache size is 0
 show global variables like "query_cache_size";
 Variable_name	Value
 query_cache_size	0

sql/set_var.cc

@@ -1046,7 +1046,19 @@ static void fix_net_retry_count(THD *thd __attribute__((unused)),
 static void fix_query_cache_size(THD *thd, enum_var_type type)
 {
 #ifdef HAVE_QUERY_CACHE
-  query_cache_size= query_cache.resize(query_cache_size);
+  ulong new_cache_size= query_cache.resize(query_cache_size);
+
+  /*
+     Note: query_cache_size is a global variable reflecting the 
+     requested cache size. See also query_cache_size_arg
+  */
+
+  if (query_cache_size != new_cache_size)
+    push_warning_printf(current_thd, MYSQL_ERROR::WARN_LEVEL_WARN,
+			ER_WARN_QC_RESIZE, ER(ER_WARN_QC_RESIZE),
+			query_cache_size, new_cache_size);
+  
+  query_cache_size= new_cache_size;
 #endif
 }
 

sql/share/errmsg.txt

@@ -4995,13 +4995,13 @@ ER_WRONG_NAME_FOR_CATALOG 42000
         spa "Nombre de catalog incorrecto '%-.100s'"
         swe "Felaktigt katalog namn '%-.100s'"
 ER_WARN_QC_RESIZE  
-	eng "Query cache failed to set size %lu (minimal value: %lu); new query cache size is %lu"
-	ger "Änderung der Query-Cache-Größe auf %lu (Minimale Zahl: %lu) fehlgeschlagen; neue Query-Cache-Größe ist %lu"
-	por "Falha em Query cache para configurar tamanho %lu (Número mínimo: %lu), novo tamanho de query cache é %lu"
-	rus "ëÅÛ ÚÁÐÒÏÓÏ× ÎÅ ÍÏÖÅÔ ÕÓÔÁÎÏ×ÉÔØ ÒÁÚÍÅÒ %lu (minimal value: %lu), ÎÏ×ÙÊ ÒÁÚÍÅÒ ËÅÛÁ ÚÐÒÏÓÏ× - %lu"
-	spa "Query cache fallada para configurar tamaño %lu (Número mínimo: %lu), nuevo tamaño de query cache es %lu"
-	swe "Storleken av "Query cache" kunde inte sättas till %lu (minsta värde: %lu); ny storlek är %lu"
-	ukr "ëÅÛ ÚÁÐÉÔ¦× ÎÅÓÐÒÏÍÏÖÅÎ ×ÓÔÁÎÏ×ÉÔÉ ÒÏÚÍ¦Ò %lu (minimal value: %lu), ÎÏ×ÉÊ ÒÏÚÍ¦Ò ËÅÛÁ ÚÁÐÉÔ¦× - %lu"
+        eng "Query cache failed to set size %lu; new query cache size is %lu"
+        ger "Änderung der Query-Cache-Größe auf %lu fehlgeschlagen; neue Query-Cache-Größe ist %lu"
+        por "Falha em Query cache para configurar tamanho %lu, novo tamanho de query cache é %lu"
+        rus "ëÅÛ ÚÁÐÒÏÓÏ× ÎÅ ÍÏÖÅÔ ÕÓÔÁÎÏ×ÉÔØ ÒÁÚÍÅÒ %lu, ÎÏ×ÙÊ ÒÁÚÍÅÒ ËÅÛÁ ÚÐÒÏÓÏ× - %lu"
+        spa "Query cache fallada para configurar tamaño %lu, nuevo tamaño de query cache es %lu"
+        swe "Storleken av "Query cache" kunde inte sättas till %lu, ny storlek är %lu"
+        ukr "ëÅÛ ÚÁÐÉÔ¦× ÎÅÓÐÒÏÍÏÖÅÎ ×ÓÔÁÎÏ×ÉÔÉ ÒÏÚÍ¦Ò %lu, ÎÏ×ÉÊ ÒÏÚÍ¦Ò ËÅÛÁ ÚÁÐÉÔ¦× - %lu"
 ER_BAD_FT_COLUMN  
         eng "Column '%-.192s' cannot be part of FULLTEXT index"
         ger "Feld '%-.192s' kann nicht Teil eines FULLTEXT-Index sein"

sql/sql_cache.cc

@@ -942,25 +942,18 @@ ulong Query_cache::resize(ulong query_cache_size_arg)
     } while (block != queries_blocks);
   }
   free_cache();
-  query_cache_size= query_cache_size_arg;
-  ::query_cache_size= init_cache();
 
-  if (::query_cache_size != query_cache_size_arg)
-  {
-    push_warning_printf(current_thd, MYSQL_ERROR::WARN_LEVEL_WARN,
-                        ER_WARN_QC_RESIZE, ER(ER_WARN_QC_RESIZE),
-                        query_cache_size_arg,
-                        get_minimal_size_limit(),
-                        ::query_cache_size);
-  }
+  query_cache_size= query_cache_size_arg;
+  new_query_cache_size= init_cache();
 
   STRUCT_LOCK(&structure_guard_mutex);
   m_cache_status= Query_cache::NO_FLUSH_IN_PROGRESS;
   pthread_cond_signal(&COND_cache_status_changed);
-  
+  if (new_query_cache_size)
+    DBUG_EXECUTE("check_querycache",check_integrity(1););
   STRUCT_UNLOCK(&structure_guard_mutex);
 
-  DBUG_RETURN(::query_cache_size);
+  DBUG_RETURN(new_query_cache_size);
 }
 
 
@@ -1823,24 +1816,6 @@ void Query_cache::init()
   DBUG_VOID_RETURN;
 }
 
-/**
-  Return the lowest possible query cache size.
-*/
-
-ulong Query_cache::get_minimal_size_limit()
-{
-  ulong approx_additional_data_size= (sizeof(Query_cache) +
-                                      sizeof(void*)*(def_query_hash_size+
-                                      def_table_hash_size));
-
-  ulong data_size= (min_allocation_unit << QUERY_CACHE_MEM_BIN_STEP_PWR2 <<
-                    QUERY_CACHE_MEM_BIN_FIRST_STEP_PWR2) +
-                    ALIGN_SIZE(1) - 1 +
-                    (1 << QUERY_CACHE_MEM_BIN_STEP_PWR2) - 1 +
-                    (1 << QUERY_CACHE_MEM_BIN_FIRST_STEP_PWR2) - 1;
-
-  return(data_size + approx_additional_data_size);
-}
 
 ulong Query_cache::init_cache()
 {

sql/sql_cache.h

@@ -282,8 +282,6 @@ private:
   void free_query_internal(Query_cache_block *point);
   void invalidate_table_internal(THD *thd, uchar *key, uint32 key_length);
 
-  ulong get_minimal_size_limit();
-
 protected:
   /*
     The following mutex is locked when searching or changing global