Added Windows v1.0

database/include/mysql/private/sql_cache.h

@@ -0,0 +1,596 @@
+/* Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; version 2 of the License.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335  USA */
+
+#ifndef _SQL_CACHE_H
+#define _SQL_CACHE_H
+
+#include "hash.h"
+#include "my_base.h"                            /* ha_rows */
+
+class MY_LOCALE;
+struct TABLE_LIST;
+class Time_zone;
+struct LEX;
+struct TABLE;
+typedef struct st_changed_table_list CHANGED_TABLE_LIST;
+
+/* Query cache */
+
+/*
+   Can't create new free memory block if unused memory in block less
+   then QUERY_CACHE_MIN_ALLOCATION_UNIT.
+   if QUERY_CACHE_MIN_ALLOCATION_UNIT == 0 then
+   QUERY_CACHE_MIN_ALLOCATION_UNIT choosed automaticaly
+*/
+#define QUERY_CACHE_MIN_ALLOCATION_UNIT		512
+
+/* inittial size of hashes */
+#define QUERY_CACHE_DEF_QUERY_HASH_SIZE		1024
+#define QUERY_CACHE_DEF_TABLE_HASH_SIZE		1024
+
+/* minimal result data size when data allocated */
+#define QUERY_CACHE_MIN_RESULT_DATA_SIZE	(1024*4)
+
+/* 
+   start estimation of first result block size only when number of queries
+   bigger then: 
+*/
+#define QUERY_CACHE_MIN_ESTIMATED_QUERIES_NUMBER 3
+
+
+
+/* memory bins size spacing (see at Query_cache::init_cache (sql_cache.cc)) */
+#define QUERY_CACHE_MEM_BIN_FIRST_STEP_PWR2	4
+#define QUERY_CACHE_MEM_BIN_STEP_PWR2		2
+#define QUERY_CACHE_MEM_BIN_PARTS_INC		1
+#define QUERY_CACHE_MEM_BIN_PARTS_MUL		1.2
+#define QUERY_CACHE_MEM_BIN_SPC_LIM_PWR2	3
+
+/* how many free blocks check when finding most suitable before other 'end'
+   of list of free blocks */
+#define QUERY_CACHE_MEM_BIN_TRY                 5
+
+/* packing parameters */
+#define QUERY_CACHE_PACK_ITERATION		2
+#define QUERY_CACHE_PACK_LIMIT			(512*1024L)
+
+#define TABLE_COUNTER_TYPE uint
+
+struct Query_cache_block;
+struct Query_cache_block_table;
+struct Query_cache_table;
+struct Query_cache_query;
+struct Query_cache_result;
+class Query_cache;
+struct Query_cache_tls;
+struct LEX;
+class THD;
+
+typedef my_bool (*qc_engine_callback)(THD *thd, char *table_key,
+                                      uint key_length,
+                                      ulonglong *engine_data);
+
+/**
+  This class represents a node in the linked chain of queries
+  belonging to one table.
+
+  @note The root of this linked list is not a query-type block, but the table-
+        type block which all queries has in common.
+*/
+struct Query_cache_block_table
+{
+  Query_cache_block_table() {}                /* Remove gcc warning */
+
+  /**
+    This node holds a position in a static table list belonging
+    to the associated query (base 0).
+  */
+  TABLE_COUNTER_TYPE n;
+
+  /**
+    Pointers to the next and previous node, linking all queries with 
+    a common table.
+  */
+  Query_cache_block_table *next, *prev;
+
+  /**
+    A pointer to the table-type block which all
+    linked queries has in common.
+  */
+  Query_cache_table *parent;
+
+  /**
+    A method to calculate the address of the query cache block
+    owning this node. The purpose of this calculation is to 
+    make it easier to move the query cache block without having
+    to modify all the pointer addresses.
+  */
+  inline Query_cache_block *block();
+};
+
+struct Query_cache_block
+{
+  Query_cache_block() {}                      /* Remove gcc warning */
+  enum block_type {FREE, QUERY, RESULT, RES_CONT, RES_BEG,
+		   RES_INCOMPLETE, TABLE, INCOMPLETE};
+
+  ulong length;					// length of all block
+  ulong used;					// length of data
+  /*
+    Not used **pprev, **prev because really needed access to pervious block:
+    *pprev to join free blocks
+    *prev to access to opposite side of list in cyclic sorted list
+  */
+  Query_cache_block *pnext,*pprev,		// physical next/previous block
+		    *next,*prev;		// logical next/previous block
+  block_type type;
+  TABLE_COUNTER_TYPE n_tables;			// number of tables in query
+
+  inline bool is_free(void) { return type == FREE; }
+  void init(ulong length);
+  void destroy();
+  uint headers_len();
+  uchar* data(void);
+  Query_cache_query *query();
+  Query_cache_table *table();
+  Query_cache_result *result();
+  Query_cache_block_table *table(TABLE_COUNTER_TYPE n);
+};
+
+struct Query_cache_query
+{
+  ulonglong limit_found_rows;
+  mysql_rwlock_t lock;
+  Query_cache_block *res;
+  Query_cache_tls *wri;
+  ulong len;
+  uint8 tbls_type;
+  unsigned int last_pkt_nr;
+
+  Query_cache_query() {}                      /* Remove gcc warning */
+  inline void init_n_lock();
+  void unlock_n_destroy();
+  inline ulonglong found_rows()		   { return limit_found_rows; }
+  inline void found_rows(ulonglong rows)   { limit_found_rows= rows; }
+  inline Query_cache_block *result()	   { return res; }
+  inline void result(Query_cache_block *p) { res= p; }
+  inline Query_cache_tls *writer()	   { return wri; }
+  inline void writer(Query_cache_tls *p)   { wri= p; }
+  inline uint8 tables_type()               { return tbls_type; }
+  inline void tables_type(uint8 type)      { tbls_type= type; }
+  inline ulong length()			   { return len; }
+  inline ulong add(ulong packet_len)	   { return(len+= packet_len); }
+  inline void length(ulong length_arg)	   { len= length_arg; }
+  inline uchar* query()
+  {
+    return (((uchar*)this) + ALIGN_SIZE(sizeof(Query_cache_query)));
+  }
+  void lock_writing();
+  void lock_reading();
+  bool try_lock_writing();
+  void unlock_writing();
+  void unlock_reading();
+};
+
+
+struct Query_cache_table
+{
+  Query_cache_table() {}                      /* Remove gcc warning */
+  char *tbl;
+  uint32 key_len;
+  uint8 table_type;
+  /* unique for every engine reference */
+  qc_engine_callback callback_func;
+  /* data need by some engines */
+  ulonglong engine_data_buff;
+
+  /**
+    The number of queries depending of this table.
+  */
+  int32 m_cached_query_count;
+  /**
+    If table included in the table hash to be found by other queries
+  */
+  my_bool hashed;
+
+  inline char *db()			     { return (char *) data(); }
+  inline char *table()			     { return tbl; }
+  inline void table(char *table_arg)	     { tbl= table_arg; }
+  inline uint32 key_length()                 { return key_len; }
+  inline void key_length(uint32 len)         { key_len= len; }
+  inline uint8 type()                        { return table_type; }
+  inline void type(uint8 t)                  { table_type= t; }
+  inline qc_engine_callback callback()       { return callback_func; }
+  inline void callback(qc_engine_callback fn){ callback_func= fn; }
+  inline ulonglong engine_data()             { return engine_data_buff; }
+  inline void engine_data(ulonglong data_arg){ engine_data_buff= data_arg; }
+  inline my_bool is_hashed()                 { return hashed; }
+  inline void set_hashed(my_bool hash)       { hashed= hash; }
+  inline uchar* data()
+  {
+    return (uchar*)(((uchar*)this)+
+		  ALIGN_SIZE(sizeof(Query_cache_table)));
+  }
+};
+
+struct Query_cache_result
+{
+  Query_cache_result() {}                     /* Remove gcc warning */
+  Query_cache_block *query;
+
+  inline uchar* data()
+  {
+    return (uchar*)(((uchar*) this)+
+		  ALIGN_SIZE(sizeof(Query_cache_result)));
+  }
+  /* data_continue (if not whole packet contained by this block) */
+  inline Query_cache_block *parent()		  { return query; }
+  inline void parent (Query_cache_block *p)	  { query=p; }
+};
+
+
+extern "C"
+{
+  uchar *query_cache_query_get_key(const uchar *record, size_t *length,
+                                   my_bool not_used);
+  uchar *query_cache_table_get_key(const uchar *record, size_t *length,
+                                   my_bool not_used);
+}
+extern "C" void query_cache_invalidate_by_MyISAM_filename(const char* filename);
+
+
+struct Query_cache_memory_bin
+{
+  Query_cache_memory_bin() {}                 /* Remove gcc warning */
+#ifndef DBUG_OFF
+  ulong size;
+#endif
+  uint number;
+  Query_cache_block *free_blocks;
+
+  inline void init(ulong size_arg)
+  {
+#ifndef DBUG_OFF
+    size = size_arg;
+#endif
+    number = 0;
+    free_blocks = 0;
+  }
+};
+
+struct Query_cache_memory_bin_step
+{
+  Query_cache_memory_bin_step() {}            /* Remove gcc warning */
+  ulong size;
+  ulong increment;
+  uint idx;
+  inline void init(ulong size_arg, uint idx_arg, ulong increment_arg)
+  {
+    size = size_arg;
+    idx = idx_arg;
+    increment = increment_arg;
+  }
+};
+
+class Query_cache
+{
+public:
+  /* Info */
+  ulong query_cache_size, query_cache_limit;
+  /* statistics */
+  ulong free_memory, queries_in_cache, hits, inserts, refused,
+    free_memory_blocks, total_blocks, lowmem_prunes;
+
+
+private:
+#ifndef DBUG_OFF
+  my_thread_id m_cache_lock_thread_id;
+#endif
+  mysql_cond_t COND_cache_status_changed;
+  uint m_requests_in_progress;
+  enum Cache_lock_status { UNLOCKED, LOCKED_NO_WAIT, LOCKED };
+  Cache_lock_status m_cache_lock_status;
+  enum Cache_staus {OK, DISABLE_REQUEST, DISABLED};
+  Cache_staus m_cache_status;
+
+  void free_query_internal(Query_cache_block *point);
+  void invalidate_table_internal(THD *thd, uchar *key, uint32 key_length);
+
+protected:
+  /*
+    The following mutex is locked when searching or changing global
+    query, tables lists or hashes. When we are operating inside the
+    query structure we locked an internal query block mutex.
+    LOCK SEQUENCE (to prevent deadlocks):
+      1. structure_guard_mutex
+      2. query block (for operation inside query (query block/results))
+
+    Thread doing cache flush releases the mutex once it sets
+    m_cache_lock_status flag, so other threads may bypass the cache as
+    if it is disabled, not waiting for reset to finish.  The exception
+    is other threads that were going to do cache flush---they'll wait
+    till the end of a flush operation.
+  */
+  mysql_mutex_t structure_guard_mutex;
+  uchar *cache;					// cache memory
+  Query_cache_block *first_block;		// physical location block list
+  Query_cache_block *queries_blocks;		// query list (LIFO)
+  Query_cache_block *tables_blocks;
+
+  Query_cache_memory_bin *bins;			// free block lists
+  Query_cache_memory_bin_step *steps;		// bins spacing info
+  HASH queries, tables;
+  /* options */
+  ulong min_allocation_unit, min_result_data_size;
+  uint def_query_hash_size, def_table_hash_size;
+  
+  uint mem_bin_num, mem_bin_steps;		// See at init_cache & find_bin
+
+  bool initialized;
+
+  /* Exclude/include from cyclic double linked list */
+  static void double_linked_list_exclude(Query_cache_block *point,
+					 Query_cache_block **list_pointer);
+  static void double_linked_list_simple_include(Query_cache_block *point,
+						Query_cache_block **
+						list_pointer);
+  static void double_linked_list_join(Query_cache_block *head_tail,
+				      Query_cache_block *tail_head);
+
+  /* The following functions require that structure_guard_mutex is locked */
+  void flush_cache();
+  my_bool free_old_query();
+  void free_query(Query_cache_block *point);
+  my_bool allocate_data_chain(Query_cache_block **result_block,
+			      ulong data_len,
+			      Query_cache_block *query_block,
+			      my_bool first_block);
+  void invalidate_table(THD *thd, TABLE_LIST *table);
+  void invalidate_table(THD *thd, TABLE *table);
+  void invalidate_table(THD *thd, uchar *key, uint32  key_length);
+  void invalidate_table(THD *thd, Query_cache_block *table_block);
+  void invalidate_query_block_list(THD *thd, 
+                                   Query_cache_block_table *list_root);
+
+  TABLE_COUNTER_TYPE
+    register_tables_from_list(THD *thd, TABLE_LIST *tables_used,
+                              TABLE_COUNTER_TYPE counter,
+                              Query_cache_block_table **block_table);
+  my_bool register_all_tables(THD *thd, Query_cache_block *block,
+			      TABLE_LIST *tables_used,
+			      TABLE_COUNTER_TYPE tables);
+  void unlink_table(Query_cache_block_table *node);
+  Query_cache_block *get_free_block (ulong len, my_bool not_less,
+				      ulong min);
+  void free_memory_block(Query_cache_block *point);
+  void split_block(Query_cache_block *block, ulong len);
+  Query_cache_block *join_free_blocks(Query_cache_block *first_block,
+				       Query_cache_block *block_in_list);
+  my_bool append_next_free_block(Query_cache_block *block,
+				 ulong add_size);
+  void exclude_from_free_memory_list(Query_cache_block *free_block);
+  void insert_into_free_memory_list(Query_cache_block *new_block);
+  my_bool move_by_type(uchar **border, Query_cache_block **before,
+		       ulong *gap, Query_cache_block *i);
+  uint find_bin(ulong size);
+  void move_to_query_list_end(Query_cache_block *block);
+  void insert_into_free_memory_sorted_list(Query_cache_block *new_block,
+					   Query_cache_block **list);
+  void pack_cache();
+  void relink(Query_cache_block *oblock,
+	      Query_cache_block *nblock,
+	      Query_cache_block *next,
+	      Query_cache_block *prev,
+	      Query_cache_block *pnext,
+	      Query_cache_block *pprev);
+  my_bool join_results(ulong join_limit);
+
+  /*
+    Following function control structure_guard_mutex
+    by themself or don't need structure_guard_mutex
+  */
+  ulong init_cache();
+  void make_disabled();
+  void free_cache();
+  Query_cache_block *write_block_data(ulong data_len, uchar* data,
+				       ulong header_len,
+				       Query_cache_block::block_type type,
+				       TABLE_COUNTER_TYPE ntab = 0);
+  my_bool append_result_data(Query_cache_block **result,
+			     ulong data_len, uchar* data,
+			     Query_cache_block *parent);
+  my_bool write_result_data(Query_cache_block **result,
+			    ulong data_len, uchar* data,
+			    Query_cache_block *parent,
+			    Query_cache_block::block_type
+			    type=Query_cache_block::RESULT);
+  inline ulong get_min_first_result_data_size();
+  inline ulong get_min_append_result_data_size();
+  Query_cache_block *allocate_block(ulong len, my_bool not_less,
+				     ulong min);
+  /*
+    If query is cacheable return number tables in query
+    (query without tables not cached)
+  */
+  TABLE_COUNTER_TYPE is_cacheable(THD *thd,
+                                  LEX *lex, TABLE_LIST *tables_used,
+                                  uint8 *tables_type);
+  TABLE_COUNTER_TYPE process_and_count_tables(THD *thd,
+                                              TABLE_LIST *tables_used,
+                                              uint8 *tables_type);
+
+  static my_bool ask_handler_allowance(THD *thd, TABLE_LIST *tables_used);
+ public:
+
+  Query_cache(ulong query_cache_limit = ULONG_MAX,
+	      ulong min_allocation_unit = QUERY_CACHE_MIN_ALLOCATION_UNIT,
+	      ulong min_result_data_size = QUERY_CACHE_MIN_RESULT_DATA_SIZE,
+	      uint def_query_hash_size = QUERY_CACHE_DEF_QUERY_HASH_SIZE,
+	      uint def_table_hash_size = QUERY_CACHE_DEF_TABLE_HASH_SIZE);
+
+  inline bool is_disabled(void) { return m_cache_status != OK; }
+  inline bool is_disable_in_progress(void)
+  { return m_cache_status == DISABLE_REQUEST; }
+
+  /* initialize cache (mutex) */
+  void init();
+  /* resize query cache (return real query size, 0 if disabled) */
+  ulong resize(ulong query_cache_size);
+  /* set limit on result size */
+  inline void result_size_limit(ulong limit){query_cache_limit=limit;}
+  /* set minimal result data allocation unit size */
+  ulong set_min_res_unit(ulong size);
+
+  /* register query in cache */
+  void store_query(THD *thd, TABLE_LIST *used_tables);
+
+  /*
+    Check if the query is in the cache and if this is true send the
+    data to client.
+  */
+  int send_result_to_client(THD *thd, char *query, uint query_length);
+
+  /* Remove all queries that uses any of the listed following tables */
+  void invalidate(THD *thd, TABLE_LIST *tables_used,
+		  my_bool using_transactions);
+  void invalidate(THD *thd, CHANGED_TABLE_LIST *tables_used);
+  void invalidate_locked_for_write(THD *thd, TABLE_LIST *tables_used);
+  void invalidate(THD *thd, TABLE *table, my_bool using_transactions);
+  void invalidate(THD *thd, const char *key, uint32  key_length,
+		  my_bool using_transactions);
+
+  /* Remove all queries that uses any of the tables in following database */
+  void invalidate(THD *thd, char *db);
+
+  /* Remove all queries that uses any of the listed following table */
+  void invalidate_by_MyISAM_filename(const char *filename);
+
+  void flush();
+  void pack(THD *thd,
+            ulong join_limit = QUERY_CACHE_PACK_LIMIT,
+	    uint iteration_limit = QUERY_CACHE_PACK_ITERATION);
+
+  void destroy();
+
+  void insert(Query_cache_tls *query_cache_tls,
+              const char *packet,
+              ulong length,
+              unsigned pkt_nr);
+  my_bool insert_table(uint key_len, char *key,
+		       Query_cache_block_table *node,
+		       uint32 db_length, uint8 cache_type,
+		       qc_engine_callback callback,
+		       ulonglong engine_data,
+                       my_bool hash);
+
+  void end_of_result(THD *thd);
+  void abort(Query_cache_tls *query_cache_tls);
+
+  /*
+    The following functions are only used when debugging
+    We don't protect these with ifndef DBUG_OFF to not have to recompile
+    everything if we want to add checks of the cache at some places.
+  */
+  void wreck(uint line, const char *message);
+  void bins_dump();
+  void cache_dump();
+  void queries_dump();
+  void tables_dump();
+  my_bool check_integrity(bool not_locked);
+  my_bool in_list(Query_cache_block * root, Query_cache_block * point,
+		  const char *name);
+  my_bool in_table_list(Query_cache_block_table * root,
+			Query_cache_block_table * point,
+			const char *name);
+  my_bool in_blocks(Query_cache_block * point);
+
+  /* Table key generation */
+  static uint filename_2_table_key (char *key, const char *filename,
+				    uint32 *db_langth);
+
+  enum Cache_try_lock_mode {WAIT, TIMEOUT, TRY};
+  bool try_lock(THD *thd, Cache_try_lock_mode mode= WAIT);
+  void lock(THD *thd);
+  void lock_and_suspend(void);
+  void unlock(void);
+
+  void disable_query_cache(THD *thd);
+};
+
+#ifdef HAVE_QUERY_CACHE
+struct Query_cache_query_flags
+{
+  unsigned int client_long_flag:1;
+  unsigned int client_protocol_41:1;
+  unsigned int protocol_type:2;
+  unsigned int more_results_exists:1;
+  unsigned int in_trans:1;
+  unsigned int autocommit:1;
+  unsigned int pkt_nr;
+  uint character_set_client_num;
+  uint character_set_results_num;
+  uint collation_connection_num;
+  ha_rows limit;
+  Time_zone *time_zone;
+  ulonglong sql_mode;
+  ulong max_sort_length;
+  ulong group_concat_max_len;
+  ulong default_week_format;
+  ulong div_precision_increment;
+  MY_LOCALE *lc_time_names;
+};
+#define QUERY_CACHE_FLAGS_SIZE sizeof(Query_cache_query_flags)
+#define QUERY_CACHE_DB_LENGTH_SIZE 2
+#include "sql_cache.h"
+#define query_cache_abort(A) query_cache.abort(A)
+#define query_cache_end_of_result(A) query_cache.end_of_result(A)
+#define query_cache_store_query(A, B) query_cache.store_query(A, B)
+#define query_cache_destroy() query_cache.destroy()
+#define query_cache_result_size_limit(A) query_cache.result_size_limit(A)
+#define query_cache_init() query_cache.init()
+#define query_cache_resize(A) query_cache.resize(A)
+#define query_cache_set_min_res_unit(A) query_cache.set_min_res_unit(A)
+#define query_cache_invalidate3(A, B, C) query_cache.invalidate(A, B, C)
+#define query_cache_invalidate1(A, B) query_cache.invalidate(A, B)
+#define query_cache_send_result_to_client(A, B, C) \
+  query_cache.send_result_to_client(A, B, C)
+#define query_cache_invalidate_by_MyISAM_filename_ref \
+  &query_cache_invalidate_by_MyISAM_filename
+/* note the "maybe": it's a read without mutex */
+#define query_cache_maybe_disabled(T)                                 \
+  (T->variables.query_cache_type == 0 || query_cache.query_cache_size == 0)
+#define query_cache_is_cacheable_query(L) \
+  (((L)->sql_command == SQLCOM_SELECT) && (L)->safe_to_cache_query)
+#else
+#define QUERY_CACHE_FLAGS_SIZE 0
+#define query_cache_store_query(A, B)     do { } while(0)
+#define query_cache_destroy()             do { } while(0)
+#define query_cache_result_size_limit(A)  do { } while(0)
+#define query_cache_init()                do { } while(0)
+#define query_cache_resize(A)             do { } while(0)
+#define query_cache_set_min_res_unit(A)   do { } while(0)
+#define query_cache_invalidate3(A, B, C)  do { } while(0)
+#define query_cache_invalidate1(A,B)      do { } while(0)
+#define query_cache_send_result_to_client(A, B, C) 0
+#define query_cache_invalidate_by_MyISAM_filename_ref NULL
+
+#define query_cache_abort(A)              do { } while(0)
+#define query_cache_end_of_result(A)      do { } while(0)
+#define query_cache_maybe_disabled(T) 1
+#define query_cache_is_cacheable_query(L) 0
+#endif /*HAVE_QUERY_CACHE*/
+
+extern Query_cache query_cache;
+#endif