Manual merge after improving concurrency for key cache reassignment

include/myisam.h:
  Auto merged
isam/isamchk.c:
  Auto merged
myisam/mi_check.c:
  Auto merged
myisam/mi_locking.c:
  Auto merged
myisam/mi_search.c:
  Auto merged
myisam/mi_write.c:
  Auto merged
myisam/myisamchk.c:
  Auto merged
myisam/myisamlog.c:
  Auto merged
mysql-test/r/func_group.result:
  Auto merged
mysys/mf_keycache.c:
  Auto merged
sql/ha_myisam.cc:
  Auto merged
sql/ha_myisam.h:
  Auto merged
sql/item_cmpfunc.h:
  Auto merged
sql/mysqld.cc:
  Auto merged
sql/set_var.cc:
  Auto merged
sql/sql_base.cc:
  Auto merged
sql/sql_lex.cc:
  Auto merged
sql/sql_lex.h:
  Auto merged
sql/sql_parse.cc:
  Auto merged
sql/sql_table.cc:
  Auto merged
sql/sql_test.cc:
  Auto merged
sql/sql_yacc.yy:
  Auto merged

include/my_base.h

@@ -46,6 +46,7 @@
 #define HA_OPEN_DELAY_KEY_WRITE		8	/* Don't update index  */
 #define HA_OPEN_ABORT_IF_CRASHED	16
 #define HA_OPEN_FOR_REPAIR		32	/* open even if crashed */
+#define HA_OPEN_TO_ASSIGN               64    /* Open for key cache assignment */
 
 	/* The following is parameter to ha_rkey() how to use key */
 
@@ -124,7 +125,8 @@ enum ha_extra_function {
   HA_EXTRA_DONT_USE_CURSOR_TO_UPDATE,	/* Cursor will not be used for update */
   HA_EXTRA_PREPARE_FOR_DELETE,
   HA_EXTRA_PREPARE_FOR_UPDATE,		/* Remove read cache if problems */
-  HA_EXTRA_PRELOAD_BUFFER_SIZE          /* Set buffer size for preloading */
+  HA_EXTRA_PRELOAD_BUFFER_SIZE,         /* Set buffer size for preloading */
+  HA_EXTRA_SET_KEY_CACHE                /* Set ref to assigned key cache  */
 };
 
 	/* The following is parameter to ha_panic() */

include/my_global.h

@@ -558,6 +558,9 @@ typedef SOCKET_SIZE_TYPE size_socket;
 #define RECORD_CACHE_SIZE	(uint) (64*1024-MALLOC_OVERHEAD)
 	/* Typical key cash */
 #define KEY_CACHE_SIZE		(uint) (8*1024*1024-MALLOC_OVERHEAD)
+	/* Default size of a key cache block  */
+#define KEY_CACHE_BLOCK_SIZE	(uint) 1024
+
 
 	/* Some things that this system doesn't have */
 

include/my_sys.h

@@ -111,8 +111,6 @@ extern int NEAR my_errno;		/* Last error in mysys */
 #define MY_WAIT_FOR_USER_TO_FIX_PANIC	60	/* in seconds */
 #define MY_WAIT_GIVE_USER_A_MESSAGE	10	/* Every 10 times of prev */
 #define MIN_COMPRESS_LENGTH		50	/* Don't compress small bl. */
-#define DEFAULT_KEYCACHE_BLOCK_SIZE	1024
-#define MAX_KEYCACHE_BLOCK_SIZE		16384
 
 	/* root_alloc flags */
 #define MY_KEEP_PREALLOC	1
@@ -266,7 +264,8 @@ enum cache_type
 
 enum flush_type
 {
-  FLUSH_KEEP, FLUSH_RELEASE, FLUSH_IGNORE_CHANGED, FLUSH_FORCE_WRITE
+  FLUSH_KEEP, FLUSH_RELEASE, FLUSH_IGNORE_CHANGED, FLUSH_FORCE_WRITE, 
+  FLUSH_REMOVE
 };
 
 typedef struct st_record_cache	/* Used when cacheing records */
@@ -503,14 +502,46 @@ my_off_t my_b_append_tell(IO_CACHE* info);
 #define my_b_bytes_in_cache(info) (uint) (*(info)->current_end - \
 					  *(info)->current_pos)
 
-/* key_cache_variables */
-typedef struct st_keycache
-{
-  ulonglong size;
-} KEY_CACHE;
-
 typedef uint32 ha_checksum;
 
+/* Pointer to a key cache data structure (see the key cache module) */
+typedef struct st_key_cache* KEY_CACHE_HANDLE;
+
+/* Key cache variable structure */
+/*
+   The structure contains the parameters of a key cache that can
+   be set and undated by regular set global statements.
+   It also contains read-only statistics parameters.
+   If the corresponding key cache data structure has been already
+   created the variable contains the key cache handle.
+   The variables are put into a named list called key_caches.
+   At present the variables are only added to this list.
+*/   
+typedef struct st_key_cache_var
+{
+  ulonglong buff_size;           /* size the memory allocated for the cache  */
+  ulong block_size;              /* size of the blocks in the key cache      */
+  ulong division_limit;          /* min. percentage of warm blocks           */
+  ulong age_threshold;           /* determines when hot block is downgraded  */
+  KEY_CACHE_HANDLE cache;        /* handles for the current and registered   */
+  ulong blocks_used;             /* number of currently used blocks          */
+  ulong blocks_changed;          /* number of currently dirty blocks         */
+  ulong cache_w_requests;        /* number of write requests (write hits)    */
+  ulong cache_write;             /* number of writes from the cache to files */
+  ulong cache_r_requests;        /* number of read requests (read hits)      */
+  ulong cache_read;              /* number of reads from files to the cache  */
+  int blocks;                    /* max number of blocks in the cache        */
+  struct st_key_cache_asmt *assign_list; /* list of assignments to the cache */
+  int assignments;               /* number of not completed assignments      */
+  void (*action)(void *);        /* optional call back function              */
+  void *extra_info;              /* ptr to extra info                        */
+} KEY_CACHE_VAR;
+
+#define DEFAULT_KEY_CACHE_NAME "default"
+extern KEY_CACHE_HANDLE *dflt_keycache;
+extern KEY_CACHE_VAR dflt_key_cache_var;
+#define DFLT_INIT_HITS  3
+
 #include <my_alloc.h>
 
 	/* Prototypes for mysys and my_func functions */
@@ -649,16 +680,26 @@ extern int flush_write_cache(RECORD_CACHE *info);
 extern long my_clock(void);
 extern sig_handler sigtstp_handler(int signal_number);
 extern void handle_recived_signals(void);
-extern int init_key_cache(ulong use_mem);
-extern int resize_key_cache(ulong use_mem);
-extern byte *key_cache_read(File file,my_off_t filepos,byte* buff,uint length,
+extern int init_key_cache(KEY_CACHE_HANDLE *pkeycache,
+                          uint key_cache_block_size,
+                          ulong use_mem, KEY_CACHE_VAR* env);
+extern int resize_key_cache(KEY_CACHE_HANDLE *pkeycache,
+                            uint key_cache_block_size, ulong use_mem);
+extern void change_key_cache_param(KEY_CACHE_HANDLE keycache);
+extern byte *key_cache_read(KEY_CACHE_HANDLE keycache,
+                            File file, my_off_t filepos, int level,
+                            byte* buff, uint length,
 			    uint block_length,int return_buffer);
-extern int key_cache_insert(File file, my_off_t filepos,
+extern int key_cache_insert(KEY_CACHE_HANDLE keycache,
+                            File file, my_off_t filepos, int level,
                             byte *buff, uint length);
-extern int key_cache_write(File file,my_off_t filepos,byte* buff,uint length,
+extern int key_cache_write(KEY_CACHE_HANDLE keycache,
+                           File file, my_off_t filepos, int level,
+                           byte* buff, uint length,
 			   uint block_length,int force_write);
-extern int flush_key_blocks(int file, enum flush_type type);
-extern void end_key_cache(void);
+extern int flush_key_blocks(KEY_CACHE_HANDLE keycache,
+                            int file, enum flush_type type);
+extern void end_key_cache(KEY_CACHE_HANDLE *pkeycache,my_bool cleanup);
 extern sig_handler my_set_alarm_variable(int signo);
 extern void my_string_ptr_sort(void *base,uint items,size_s size);
 extern void radixsort_for_str_ptr(uchar* base[], uint number_of_elements,

include/myisam.h

@@ -408,6 +408,9 @@ my_bool mi_test_if_sort_rep(MI_INFO *info, ha_rows rows, ulonglong key_map,
 int mi_init_bulk_insert(MI_INFO *info, ulong cache_size, ha_rows rows);
 void mi_flush_bulk_insert(MI_INFO *info, uint inx);
 void mi_end_bulk_insert(MI_INFO *info);
+int mi_assign_to_keycache(MI_INFO *info, ulonglong key_map, 
+                          KEY_CACHE_VAR *key_cache, 
+                          pthread_mutex_t *assign_lock);
 int mi_preload(MI_INFO *info, ulonglong key_map, my_bool ignore_leaves);
 
 #ifdef	__cplusplus

isam/_locking.c

@@ -50,7 +50,7 @@ int nisam_lock_database(N_INFO *info, int lock_type)
     else
       count= --share->w_locks;
     if (info->lock_type == F_WRLCK && !share->w_locks &&
-	flush_key_blocks(share->kfile,FLUSH_KEEP))
+	flush_key_blocks(*dflt_keycache,share->kfile,FLUSH_KEEP))
       error=my_errno;
     if (info->opt_flag & (READ_CACHE_USED | WRITE_CACHE_USED))
       if (end_io_cache(&info->rec_cache))
@@ -329,7 +329,7 @@ int _nisam_test_if_changed(register N_INFO *info)
 	share->state.uniq    != info->last_uniq)
     {						/* Keyfile has changed */
       if (share->state.process != share->this_process)
-	VOID(flush_key_blocks(share->kfile,FLUSH_RELEASE));
+	VOID(flush_key_blocks(*dflt_keycache,share->kfile,FLUSH_RELEASE));
       share->last_process=share->state.process;
       info->last_loop=	share->state.loop;
       info->last_uniq=	share->state.uniq;

isam/_page.c

@@ -27,7 +27,8 @@ uchar *_nisam_fetch_keypage(register N_INFO *info, N_KEYDEF *keyinfo,
 			    my_off_t page, uchar *buff, int return_buffer)
 {
   uchar *tmp;
-  tmp=(uchar*) key_cache_read(info->s->kfile,page,(byte*) buff,
+  tmp=(uchar*) key_cache_read(*dflt_keycache,
+                              info->s->kfile,page,DFLT_INIT_HITS,(byte*) buff,
 			      (uint) keyinfo->base.block_length,
 			      (uint) keyinfo->base.block_length,
 			      return_buffer);
@@ -83,7 +84,9 @@ int _nisam_write_keypage(register N_INFO *info, register N_KEYDEF *keyinfo,
     length=keyinfo->base.block_length;
   }
 #endif
-  return (key_cache_write(info->s->kfile,page,(byte*) buff,length,
+  return (key_cache_write(*dflt_keycache,
+                          info->s->kfile,page,DFLT_INIT_HITS,
+                          (byte*) buff,length,
 			  (uint) keyinfo->base.block_length,
 			  (int) (info->lock_type != F_UNLCK)));
 } /* nisam_write_keypage */
@@ -99,7 +102,9 @@ int _nisam_dispose(register N_INFO *info, N_KEYDEF *keyinfo, my_off_t pos)
 
   old_link=info->s->state.key_del[keynr];
   info->s->state.key_del[keynr]=(ulong) pos;
-  DBUG_RETURN(key_cache_write(info->s->kfile,pos,(byte*) &old_link,
+  DBUG_RETURN(key_cache_write(*dflt_keycache,
+                              info->s->kfile,pos,DFLT_INIT_HITS,
+                              (byte*) &old_link,
 			      sizeof(long),
 			      (uint) keyinfo->base.block_length,
 			      (int) (info->lock_type != F_UNLCK)));
@@ -126,7 +131,8 @@ ulong _nisam_new(register N_INFO *info, N_KEYDEF *keyinfo)
   }
   else
   {
-    if (!key_cache_read(info->s->kfile,pos,
+    if (!key_cache_read(*dflt_keycache,
+                        info->s->kfile,pos,DFLT_INIT_HITS,
 			(byte*) &info->s->state.key_del[keynr],
 			(uint) sizeof(long),
 			(uint) keyinfo->base.block_length,0))

isam/close.c

@@ -56,7 +56,8 @@ int nisam_close(register N_INFO *info)
 
   if (flag)
   {
-    if (share->kfile >= 0 && flush_key_blocks(share->kfile,FLUSH_RELEASE))
+    if (share->kfile >= 0 && 
+        flush_key_blocks(*dflt_keycache,share->kfile,FLUSH_RELEASE))
       error=my_errno;
     if (share->kfile >= 0 && my_close(share->kfile,MYF(0)))
       error = my_errno;

isam/isamchk.c

@@ -516,7 +516,8 @@ static int nisamchk(my_string filename)
       if (!rep_quick)
       {
 	if (testflag & T_EXTEND)
-	  VOID(init_key_cache(use_buffers));
+	  VOID(init_key_cache(dflt_keycache,KEY_CACHE_BLOCK_SIZE,
+                              use_buffers,&dflt_key_cache_var));
 	VOID(init_io_cache(&read_cache,datafile,(uint) read_buffer_length,
 			  READ_CACHE,share->pack.header_length,1,
 			  MYF(MY_WME)));
@@ -1459,7 +1460,8 @@ my_string name;
     printf("Data records: %lu\n",(ulong) share->state.records);
   }
 
-  VOID(init_key_cache(use_buffers));
+  VOID(init_key_cache(dflt_keycache,KEY_CACHE_BLOCK_SIZE,use_buffers,
+                      &dflt_key_cache_var));
   if (init_io_cache(&read_cache,info->dfile,(uint) read_buffer_length,
 		   READ_CACHE,share->pack.header_length,1,MYF(MY_WME)))
     goto err;
@@ -1887,12 +1889,12 @@ static void lock_memory(void)
 static int flush_blocks(file)
 File file;
 {
-  if (flush_key_blocks(file,FLUSH_RELEASE))
+  if (flush_key_blocks(dflt_keycache,file,FLUSH_RELEASE))
   {
     print_error("%d when trying to write bufferts",my_errno);
     return(1);
   }
-  end_key_cache();
+  end_key_cache(dflt_keycache,1);
   return 0;
 } /* flush_blocks */
 
@@ -1936,7 +1938,8 @@ int write_info;
   if (share->state.key_root[sort_key] == NI_POS_ERROR)
     DBUG_RETURN(0);				/* Nothing to do */
 
-  init_key_cache(use_buffers);
+  init_key_cache(dflt_keycache,KEY_CACHE_BLOCK_SIZE,use_buffers,
+                 &dflt_key_cache_var);
   if (init_io_cache(&info->rec_cache,-1,(uint) write_buffer_length,
 		   WRITE_CACHE,share->pack.header_length,1,
 		   MYF(MY_WME | MY_WAIT_IF_FULL)))

isam/isamlog.c

@@ -329,8 +329,8 @@ static int examine_log(my_string file_name, char **table_names)
   bzero((gptr) com_count,sizeof(com_count));
   init_tree(&tree,0,0,sizeof(file_info),(qsort_cmp2) file_info_compare,1,
 	    (tree_element_free) file_info_free, NULL);
-  VOID(init_key_cache(KEY_CACHE_SIZE));
-
+  VOID(init_key_cache(dflt_keycache,KEY_CACHE_BLOCK_SIZE,KEY_CACHE_SIZE,
+                      &dflt_key_cache_var));
   files_open=0; access_time=0;
   while (access_time++ != number_of_commands &&
 	 !my_b_read(&cache,(byte*) head,9))
@@ -622,7 +622,7 @@ static int examine_log(my_string file_name, char **table_names)
       goto end;
     }
   }
-  end_key_cache();
+  end_key_cache(dflt_keycache,1);
   delete_tree(&tree);
   VOID(end_io_cache(&cache));
   VOID(my_close(file,MYF(0)));
@@ -642,7 +642,7 @@ static int examine_log(my_string file_name, char **table_names)
 	       llstr(isamlog_filepos,llbuff)));
   fflush(stderr);
  end:
-  end_key_cache();
+  end_key_cache(dflt_keycache,1);
   delete_tree(&tree);
   VOID(end_io_cache(&cache));
   VOID(my_close(file,MYF(0)));

isam/panic.c

@@ -48,7 +48,7 @@ int nisam_panic(enum ha_panic_function flag)
       if (info->s->base.options & HA_OPTION_READ_ONLY_DATA)
 	break;
 #endif
-      if (flush_key_blocks(info->s->kfile,FLUSH_RELEASE))
+      if (flush_key_blocks(*dflt_keycache,info->s->kfile,FLUSH_RELEASE))
 	error=my_errno;
       if (info->opt_flag & WRITE_CACHE_USED)
 	if (flush_io_cache(&info->rec_cache))

isam/test2.c

@@ -156,7 +156,7 @@ int main(int argc, char *argv[])
     goto err;
   printf("- Writing key:s\n");
   if (key_cacheing)
-    init_key_cache(IO_SIZE*16);		/* Use a small cache */
+    init_key_cache(dflt_keycache,512,IO_SIZE*16,0);		/* Use a small cache */
   if (locking)
     nisam_lock_database(file,F_WRLCK);
   if (write_cacheing)
@@ -674,7 +674,7 @@ end:
     puts("Locking used");
   if (use_blob)
     puts("blobs used");
-  end_key_cache();
+  end_key_cache(&dflt_keycache,1);
   if (blob_buffer)
     my_free(blob_buffer,MYF(0));
   my_end(MY_CHECK_ERROR | MY_GIVE_INFO);

isam/test3.c

@@ -173,7 +173,7 @@ void start_test(int id)
     exit(1);
   }
   if (key_cacheing && rnd(2) == 0)
-    init_key_cache(65536L);
+    init_key_cache(dflt_keycache,512,65536L,0);
   printf("Process %d, pid: %d\n",id,(int) getpid()); fflush(stdout);
 
   for (error=i=0 ; i < tests && !error; i++)

myisam/Makefile.am

@@ -47,7 +47,7 @@ libmyisam_a_SOURCES =	mi_open.c mi_extra.c mi_info.c mi_rkey.c \
 			mi_range.c mi_dbug.c mi_checksum.c mi_log.c \
 			mi_changed.c mi_static.c mi_delete_all.c \
 			mi_delete_table.c mi_rename.c  mi_check.c \
-			mi_preload.c \
+			mi_keycache.c mi_preload.c \
 			ft_parser.c ft_stopwords.c ft_static.c \
 			ft_update.c ft_boolean_search.c ft_nlq_search.c sort.c \
 			rt_index.c rt_key.c rt_mbr.c rt_split.c sp_key.c

myisam/mi_check.c

@@ -230,7 +230,9 @@ static int check_k_link(MI_CHECK *param, register MI_INFO *info, uint nr)
     if (next_link > info->state->key_file_length ||
 	next_link & (info->s->blocksize-1))
       DBUG_RETURN(1);
-    if (!(buff=key_cache_read(info->s->kfile, next_link, (byte*) info->buff,
+    if (!(buff=key_cache_read(*info->s->keycache,
+                              info->s->kfile, next_link, DFLT_INIT_HITS,
+                              (byte*) info->buff,
 			      myisam_block_size, block_size, 1)))
       DBUG_RETURN(1);
     next_link=mi_sizekorr(buff);
@@ -259,7 +261,8 @@ int chk_size(MI_CHECK *param, register MI_INFO *info)
 
   if (!(param->testflag & T_SILENT)) puts("- check file-size");
 
-  flush_key_blocks(info->s->kfile, FLUSH_FORCE_WRITE); /* If called externally */
+  flush_key_blocks(*info->s->keycache,
+                info->s->kfile, FLUSH_FORCE_WRITE); /* If called externally */
 
   size=my_seek(info->s->kfile,0L,MY_SEEK_END,MYF(0));
   if ((skr=(my_off_t) info->state->key_file_length) != size)
@@ -369,8 +372,8 @@ int chk_key(MI_CHECK *param, register MI_INFO *info)
     if (share->state.key_root[key] == HA_OFFSET_ERROR &&
 	(info->state->records == 0 || keyinfo->flag & HA_FULLTEXT))
       continue;
-    if (!_mi_fetch_keypage(info,keyinfo,share->state.key_root[key],info->buff,
-			   0))
+    if (!_mi_fetch_keypage(info,keyinfo,share->state.key_root[key],
+                           DFLT_INIT_HITS,info->buff,0))
     {
       mi_check_print_error(param,"Can't read indexpage from filepos: %s",
 		  llstr(share->state.key_root[key],buff));
@@ -548,7 +551,8 @@ static int chk_index(MI_CHECK *param, MI_INFO *info, MI_KEYDEF *keyinfo,
 	info->state->key_file_length=(max_length &
 				      ~ (my_off_t) (info->s->blocksize-1));
       }
-      if (!_mi_fetch_keypage(info,keyinfo,next_page,temp_buff,0))
+      if (!_mi_fetch_keypage(info,keyinfo,next_page,
+                             DFLT_INIT_HITS,temp_buff,0))
       {
 	mi_check_print_error(param,"Can't read key from filepos: %s",llstr(next_page,llbuff));
 	goto err;
@@ -1120,7 +1124,8 @@ int mi_repair(MI_CHECK *param, register MI_INFO *info,
   param->testflag|=T_REP; /* for easy checking */
 
   if (!param->using_global_keycache)
-    VOID(init_key_cache(param->use_buffers));
+    VOID(init_key_cache(dflt_keycache,dflt_key_cache_var.block_size,
+                        param->use_buffers,&dflt_key_cache_var));
 
   if (init_io_cache(&param->read_cache,info->dfile,
 		    (uint) param->read_buffer_length,
@@ -1441,7 +1446,8 @@ int movepoint(register MI_INFO *info, byte *record, my_off_t oldpos,
 	nod_flag=mi_test_if_nod(info->buff);
 	_mi_dpointer(info,info->int_keypos-nod_flag-
 		     info->s->rec_reflength,newpos);
-	if (_mi_write_keypage(info,keyinfo,info->last_keypage,info->buff))
+	if (_mi_write_keypage(info,keyinfo,info->last_keypage,
+                              DFLT_INIT_HITS,info->buff))
 	  DBUG_RETURN(-1);
       }
       else
@@ -1478,13 +1484,13 @@ void lock_memory(MI_CHECK *param __attribute__((unused)))
 
 int flush_blocks(MI_CHECK *param, File file)
 {
-  if (flush_key_blocks(file,FLUSH_RELEASE))
+  if (flush_key_blocks(*dflt_keycache,file,FLUSH_RELEASE))
   {
     mi_check_print_error(param,"%d when trying to write bufferts",my_errno);
     return(1);
   }
   if (!param->using_global_keycache)
-    end_key_cache();
+    end_key_cache(dflt_keycache,1);
   return 0;
 } /* flush_blocks */
 
@@ -1539,7 +1545,7 @@ int mi_sort_index(MI_CHECK *param, register MI_INFO *info, my_string name)
   }
 
   /* Flush key cache for this file if we are calling this outside myisamchk */
-  flush_key_blocks(share->kfile, FLUSH_IGNORE_CHANGED);
+  flush_key_blocks(*share->keycache,share->kfile, FLUSH_IGNORE_CHANGED);
 
   share->state.version=(ulong) time((time_t*) 0);
   old_state= share->state;			/* save state if not stored */
@@ -1603,7 +1609,7 @@ static int sort_one_index(MI_CHECK *param, MI_INFO *info, MI_KEYDEF *keyinfo,
     mi_check_print_error(param,"Not Enough memory");
     DBUG_RETURN(-1);
   }
-  if (!_mi_fetch_keypage(info,keyinfo,pagepos,buff,0))
+  if (!_mi_fetch_keypage(info,keyinfo,pagepos,DFLT_INIT_HITS,buff,0))
   {
     mi_check_print_error(param,"Can't read key block from filepos: %s",
 		llstr(pagepos,llbuff));
@@ -1849,7 +1855,7 @@ int mi_repair_by_sort(MI_CHECK *param, register MI_INFO *info,
       Flush key cache for this file if we are calling this outside
       myisamchk
     */
-    flush_key_blocks(share->kfile, FLUSH_IGNORE_CHANGED);
+    flush_key_blocks(*share->keycache,share->kfile, FLUSH_IGNORE_CHANGED);
     /* Clear the pointers to the given rows */
     for (i=0 ; i < share->base.keys ; i++)
       share->state.key_root[i]= HA_OFFSET_ERROR;
@@ -1859,7 +1865,7 @@ int mi_repair_by_sort(MI_CHECK *param, register MI_INFO *info,
   }
   else
   {
-    if (flush_key_blocks(share->kfile, FLUSH_FORCE_WRITE))
+    if (flush_key_blocks(*share->keycache,share->kfile, FLUSH_FORCE_WRITE))
       goto err;
     key_map= ~key_map;				/* Create the missing keys */
   }
@@ -2212,7 +2218,7 @@ int mi_repair_parallel(MI_CHECK *param, register MI_INFO *info,
       Flush key cache for this file if we are calling this outside
       myisamchk
     */
-    flush_key_blocks(share->kfile, FLUSH_IGNORE_CHANGED);
+    flush_key_blocks(*share->keycache,share->kfile, FLUSH_IGNORE_CHANGED);
     /* Clear the pointers to the given rows */
     for (i=0 ; i < share->base.keys ; i++)
       share->state.key_root[i]= HA_OFFSET_ERROR;
@@ -2222,7 +2228,7 @@ int mi_repair_parallel(MI_CHECK *param, register MI_INFO *info,
   }
   else
   {
-    if (flush_key_blocks(share->kfile, FLUSH_FORCE_WRITE))
+    if (flush_key_blocks(*share->keycache,share->kfile, FLUSH_FORCE_WRITE))
       goto err;
     key_map= ~key_map;				/* Create the missing keys */
   }
@@ -3337,13 +3343,13 @@ static int sort_insert_key(MI_SORT_PARAM *sort_param,
   bzero((byte*) anc_buff+key_block->last_length,
 	keyinfo->block_length- key_block->last_length);
   key_file_length=info->state->key_file_length;
-  if ((filepos=_mi_new(info,keyinfo)) == HA_OFFSET_ERROR)
+  if ((filepos=_mi_new(info,keyinfo,DFLT_INIT_HITS)) == HA_OFFSET_ERROR)
     DBUG_RETURN(1);
 
   /* If we read the page from the key cache, we have to write it back to it */
   if (key_file_length == info->state->key_file_length)
   {
-    if (_mi_write_keypage(info, keyinfo, filepos, anc_buff))
+    if (_mi_write_keypage(info, keyinfo, filepos, DFLT_INIT_HITS, anc_buff))
       DBUG_RETURN(1);
   }
   else if (my_pwrite(info->s->kfile,(byte*) anc_buff,
@@ -3441,13 +3447,14 @@ int flush_pending_blocks(MI_SORT_PARAM *sort_param)
       _mi_kpointer(info,key_block->end_pos,filepos);
     key_file_length=info->state->key_file_length;
     bzero((byte*) key_block->buff+length, keyinfo->block_length-length);
-    if ((filepos=_mi_new(info,keyinfo)) == HA_OFFSET_ERROR)
+    if ((filepos=_mi_new(info,keyinfo,DFLT_INIT_HITS)) == HA_OFFSET_ERROR)
       DBUG_RETURN(1);
 
     /* If we read the page from the key cache, we have to write it back */
     if (key_file_length == info->state->key_file_length)
     {
-      if (_mi_write_keypage(info, keyinfo, filepos, key_block->buff))
+      if (_mi_write_keypage(info, keyinfo, filepos,
+                            DFLT_INIT_HITS, key_block->buff))
 	DBUG_RETURN(1);
     }
     else if (my_pwrite(info->s->kfile,(byte*) key_block->buff,

myisam/mi_close.c

@@ -64,7 +64,7 @@ int mi_close(register MI_INFO *info)
   if (flag)
   {
     if (share->kfile >= 0 &&
-	flush_key_blocks(share->kfile,
+	flush_key_blocks(*share->keycache,share->kfile,
 			 share->temporary ? FLUSH_IGNORE_CHANGED :
 			 FLUSH_RELEASE))
       error=my_errno;

myisam/mi_delete.c

@@ -155,7 +155,7 @@ static int _mi_ck_real_delete(register MI_INFO *info, MI_KEYDEF *keyinfo,
     DBUG_RETURN(my_errno=ENOMEM);
   }
   DBUG_PRINT("info",("root_page: %ld",old_root));
-  if (!_mi_fetch_keypage(info,keyinfo,old_root,root_buff,0))
+  if (!_mi_fetch_keypage(info,keyinfo,old_root,DFLT_INIT_HITS,root_buff,0))
   {
     error= -1;
     goto err;
@@ -179,11 +179,12 @@ static int _mi_ck_real_delete(register MI_INFO *info, MI_KEYDEF *keyinfo,
 	  *root=_mi_kpos(nod_flag,root_buff+2+nod_flag);
 	else
 	  *root=HA_OFFSET_ERROR;
-	if (_mi_dispose(info,keyinfo,old_root))
+	if (_mi_dispose(info,keyinfo,old_root,DFLT_INIT_HITS))
 	  error= -1;
       }
       else
-	error=_mi_write_keypage(info,keyinfo,old_root,root_buff);
+	error=_mi_write_keypage(info,keyinfo,old_root,
+                                DFLT_INIT_HITS,root_buff);
     }
   }
 err:
@@ -253,7 +254,7 @@ static int d_search(register MI_INFO *info, register MI_KEYDEF *keyinfo,
       {
         /* the last entry in sub-tree */
         DBUG_PRINT("info",("FT2: the last entry"));
-        _mi_dispose(info, keyinfo, root);
+        _mi_dispose(info, keyinfo, root,DFLT_INIT_HITS);
         /* fall through to normal delete */
       }
       else
@@ -268,7 +269,8 @@ static int d_search(register MI_INFO *info, register MI_KEYDEF *keyinfo,
         subkeys++;
         ft_intXstore(kpos, subkeys);
         if (!ret_value)
-          ret_value=_mi_write_keypage(info,keyinfo,page,anc_buff);
+          ret_value=_mi_write_keypage(info,keyinfo,page,
+                                      DFLT_INIT_HITS,anc_buff);
         DBUG_PRINT("exit",("Return: %d",ret_value));
         DBUG_RETURN(ret_value);
       }
@@ -287,7 +289,7 @@ static int d_search(register MI_INFO *info, register MI_KEYDEF *keyinfo,
       DBUG_PRINT("exit",("Return: %d",-1));
       DBUG_RETURN(-1);
     }
-    if (!_mi_fetch_keypage(info,keyinfo,leaf_page,leaf_buff,0))
+    if (!_mi_fetch_keypage(info,keyinfo,leaf_page,DFLT_INIT_HITS,leaf_buff,0))
       goto err;
   }
 
@@ -319,7 +321,7 @@ static int d_search(register MI_INFO *info, register MI_KEYDEF *keyinfo,
     mi_putint(anc_buff,length,nod_flag);
     if (!nod_flag)
     {						/* On leaf page */
-      if (_mi_write_keypage(info,keyinfo,page,anc_buff))
+      if (_mi_write_keypage(info,keyinfo,page,DFLT_INIT_HITS,anc_buff))
       {
         DBUG_PRINT("exit",("Return: %d",-1));
 	DBUG_RETURN(-1);
@@ -354,7 +356,7 @@ static int d_search(register MI_INFO *info, register MI_KEYDEF *keyinfo,
     ret_value=_mi_split_page(info,keyinfo,key,anc_buff,lastkey,0) | 2;
   }
   if (save_flag && ret_value != 1)
-    ret_value|=_mi_write_keypage(info,keyinfo,page,anc_buff);
+    ret_value|=_mi_write_keypage(info,keyinfo,page,DFLT_INIT_HITS,anc_buff);
   else
   {
     DBUG_DUMP("page",(byte*) anc_buff,mi_getint(anc_buff));
@@ -398,7 +400,7 @@ static int del(register MI_INFO *info, register MI_KEYDEF *keyinfo, uchar *key,
     if (!(next_buff= (uchar*) my_alloca((uint) keyinfo->block_length+
 					MI_MAX_KEY_BUFF*2)))
       DBUG_RETURN(-1);
-    if (!_mi_fetch_keypage(info,keyinfo,next_page,next_buff,0))
+    if (!_mi_fetch_keypage(info,keyinfo,next_page,DFLT_INIT_HITS,next_buff,0))
       ret_value= -1;
     else
     {
@@ -426,7 +428,7 @@ static int del(register MI_INFO *info, register MI_KEYDEF *keyinfo, uchar *key,
 			       (uchar*) 0,(uchar*) 0,(my_off_t) 0,0);
 	}
       }
-      if (_mi_write_keypage(info,keyinfo,leaf_page,leaf_buff))
+      if (_mi_write_keypage(info,keyinfo,leaf_page,DFLT_INIT_HITS,leaf_buff))
 	goto err;
     }
     my_afree((byte*) next_buff);
@@ -436,7 +438,7 @@ static int del(register MI_INFO *info, register MI_KEYDEF *keyinfo, uchar *key,
 	/* Remove last key from leaf page */
 
   mi_putint(leaf_buff,key_start-leaf_buff,nod_flag);
-  if (_mi_write_keypage(info,keyinfo,leaf_page,leaf_buff))
+  if (_mi_write_keypage(info,keyinfo,leaf_page,DFLT_INIT_HITS,leaf_buff))
     goto err;
 
 	/* Place last key in ancestor page on deleted key position */
@@ -524,7 +526,7 @@ static int underflow(register MI_INFO *info, register MI_KEYDEF *keyinfo,
       goto err;
     }
     next_page= _mi_kpos(key_reflength,next_keypos);
-    if (!_mi_fetch_keypage(info,keyinfo,next_page,buff,0))
+    if (!_mi_fetch_keypage(info,keyinfo,next_page,DFLT_INIT_HITS,buff,0))
       goto err;
     buff_length=mi_getint(buff);
     DBUG_DUMP("next",(byte*) buff,buff_length);
@@ -563,7 +565,7 @@ static int underflow(register MI_INFO *info, register MI_KEYDEF *keyinfo,
     if (buff_length <= keyinfo->block_length)
     {						/* Keys in one page */
       memcpy((byte*) leaf_buff,(byte*) buff,(size_t) buff_length);
-      if (_mi_dispose(info,keyinfo,next_page))
+      if (_mi_dispose(info,keyinfo,next_page,DFLT_INIT_HITS))
        goto err;
     }
     else
@@ -612,10 +614,10 @@ static int underflow(register MI_INFO *info, register MI_KEYDEF *keyinfo,
       (*keyinfo->store_key)(keyinfo,buff+p_length,&s_temp);
       mi_putint(buff,length+t_length+p_length,nod_flag);
 
-      if (_mi_write_keypage(info,keyinfo,next_page,buff))
+      if (_mi_write_keypage(info,keyinfo,next_page,DFLT_INIT_HITS,buff))
 	goto err;
     }
-    if (_mi_write_keypage(info,keyinfo,leaf_page,leaf_buff))
+    if (_mi_write_keypage(info,keyinfo,leaf_page,DFLT_INIT_HITS,leaf_buff))
       goto err;
     DBUG_RETURN(anc_length <= ((info->quick_mode ? MI_MIN_BLOCK_LENGTH :
 				(uint) keyinfo->underflow_block_length)));
@@ -627,7 +629,7 @@ static int underflow(register MI_INFO *info, register MI_KEYDEF *keyinfo,
   if (!keypos)
     goto err;
   next_page= _mi_kpos(key_reflength,keypos);
-  if (!_mi_fetch_keypage(info,keyinfo,next_page,buff,0))
+  if (!_mi_fetch_keypage(info,keyinfo,next_page,DFLT_INIT_HITS,buff,0))
       goto err;
   buff_length=mi_getint(buff);
   endpos=buff+buff_length;
@@ -671,7 +673,7 @@ static int underflow(register MI_INFO *info, register MI_KEYDEF *keyinfo,
 
   if (buff_length <= keyinfo->block_length)
   {						/* Keys in one page */
-    if (_mi_dispose(info,keyinfo,leaf_page))
+    if (_mi_dispose(info,keyinfo,leaf_page,DFLT_INIT_HITS))
       goto err;
   }
   else
@@ -718,11 +720,11 @@ static int underflow(register MI_INFO *info, register MI_KEYDEF *keyinfo,
 	  (size_t) length);
     (*keyinfo->store_key)(keyinfo,leaf_buff+p_length,&s_temp);
     mi_putint(leaf_buff,length+t_length+p_length,nod_flag);
-    if (_mi_write_keypage(info,keyinfo,leaf_page,leaf_buff))
+    if (_mi_write_keypage(info,keyinfo,leaf_page,DFLT_INIT_HITS,leaf_buff))
       goto err;
     mi_putint(buff,endpos-buff,nod_flag);
   }
-  if (_mi_write_keypage(info,keyinfo,next_page,buff))
+  if (_mi_write_keypage(info,keyinfo,next_page,DFLT_INIT_HITS,buff))
     goto err;
   DBUG_RETURN(anc_length <= (uint) keyinfo->block_length/2);
 err:

myisam/mi_delete_all.c

@@ -53,7 +53,7 @@ int mi_delete_all_rows(MI_INFO *info)
     If we are using delayed keys or if the user has done changes to the tables
     since it was locked then there may be key blocks in the key cache
   */
-  flush_key_blocks(share->kfile, FLUSH_IGNORE_CHANGED);
+  flush_key_blocks(*share->keycache, share->kfile, FLUSH_IGNORE_CHANGED);
   if (my_chsize(info->dfile, 0, 0, MYF(MY_WME)) ||
       my_chsize(share->kfile, share->base.keystart, 0, MYF(MY_WME))  )
     goto err;

myisam/mi_extra.c

@@ -283,7 +283,7 @@ int mi_extra(MI_INFO *info, enum ha_extra_function function, void *extra_arg)
 #ifdef __WIN__
     /* Close the isam and data files as Win32 can't drop an open table */
     pthread_mutex_lock(&share->intern_lock);
-    if (flush_key_blocks(share->kfile,
+    if (flush_key_blocks(*share->keycache, share->kfile,
 			 (function == HA_EXTRA_FORCE_REOPEN ?
 			  FLUSH_RELEASE : FLUSH_IGNORE_CHANGED)))
     {
@@ -329,7 +329,7 @@ int mi_extra(MI_INFO *info, enum ha_extra_function function, void *extra_arg)
     break;
   case HA_EXTRA_FLUSH:
     if (!share->temporary)
-      flush_key_blocks(share->kfile,FLUSH_KEEP);
+      flush_key_blocks(*share->keycache,share->kfile,FLUSH_KEEP);
 #ifdef HAVE_PWRITE
     _mi_decrement_open_count(info);
 #endif
@@ -374,6 +374,9 @@ int mi_extra(MI_INFO *info, enum ha_extra_function function, void *extra_arg)
   case HA_EXTRA_PRELOAD_BUFFER_SIZE:
     info->preload_buff_size= *((ulong *) extra_arg); 
     break;
+  case HA_EXTRA_SET_KEY_CACHE:
+    share->reg_keycache= share->keycache= (KEY_CACHE_HANDLE *) extra_arg;
+    break;
   case HA_EXTRA_KEY_CACHE:
   case HA_EXTRA_NO_KEY_CACHE:
   default:

myisam/mi_keycache.c

+/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
+
+   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; either version 2 of the License, or
+   (at your option) any later version.
+
+   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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
+
+/*
+  Key cache assignments
+*/
+
+#include "myisamdef.h"
+
+
+/*
+  Assign pages of the index file for a table to a key cache
+
+  SYNOPSIS
+    mi_assign_to_keycache()
+      info          open table
+      map           map of indexes to assign to the key cache 
+      key_cache_ptr pointer to the key cache handle
+
+  RETURN VALUE
+    0 if a success. error code - otherwise.
+
+  NOTES.
+    At present pages for all indexes must be assigned to the same key cache.
+    In future only pages for indexes specified in the key_map parameter
+    of the table will be assigned to the specified key cache.
+*/
+
+typedef struct st_assign_extra_info
+{
+  pthread_mutex_t *lock; 
+  struct st_my_thread_var *waiting_thread;
+} ASSIGN_EXTRA_INFO;
+
+static void remove_key_cache_assign(void *arg)
+{
+  KEY_CACHE_VAR *key_cache= (KEY_CACHE_VAR *) arg;
+  ASSIGN_EXTRA_INFO *extra_info= (ASSIGN_EXTRA_INFO *) key_cache->extra_info;
+  struct st_my_thread_var *waiting_thread;
+  pthread_mutex_t *lock= extra_info->lock;
+  pthread_mutex_lock(lock);
+  if (!(--key_cache->assignments) && 
+      (waiting_thread = extra_info->waiting_thread))
+  {
+    my_free(extra_info, MYF(0));
+    key_cache->extra_info= 0;
+    if (waiting_thread != my_thread_var)
+      pthread_cond_signal(&waiting_thread->suspend);
+  }
+  pthread_mutex_unlock(lock);
+}
+
+int mi_assign_to_keycache(MI_INFO *info, ulonglong key_map, 
+                          KEY_CACHE_VAR *key_cache, 
+                          pthread_mutex_t *assign_lock)
+{
+  ASSIGN_EXTRA_INFO *extra_info;
+  int error= 0;
+  MYISAM_SHARE* share= info->s;
+
+  DBUG_ENTER("mi_assign_to_keycache");
+
+  share->reg_keycache= &key_cache->cache;
+  pthread_mutex_lock(assign_lock);
+  if (!(extra_info= (ASSIGN_EXTRA_INFO *) key_cache->extra_info))
+  {
+    if (!(extra_info= (ASSIGN_EXTRA_INFO*) my_malloc(sizeof(ASSIGN_EXTRA_INFO),
+					           MYF(MY_WME | MY_ZEROFILL))))
+      DBUG_RETURN(HA_ERR_OUT_OF_MEM);
+    key_cache->extra_info= extra_info;
+    key_cache->action= remove_key_cache_assign;
+    extra_info->lock= assign_lock;
+  }
+  key_cache->assignments++;
+  pthread_mutex_unlock(assign_lock);
+  
+  if (!(info->lock_type == F_WRLCK && share->w_locks))
+  {
+    if (flush_key_blocks(*share->keycache, share->kfile, FLUSH_REMOVE))
+    {
+      error=my_errno;
+      mi_mark_crashed(info);		/* Mark that table must be checked */
+    }
+    share->keycache= &key_cache->cache;
+  }
+  else
+  {
+    extra_info->waiting_thread= my_thread_var;
+  }
+
+    
+  DBUG_RETURN(error);
+}
+

myisam/mi_locking.c

@@ -34,6 +34,7 @@ int mi_lock_database(MI_INFO *info, int lock_type)
   uint count;
   MYISAM_SHARE *share=info->s;
   uint flag;
+  uint switch_fl= 0;
   DBUG_ENTER("mi_lock_database");
   DBUG_PRINT("info",("lock_type: %d", lock_type));
 
@@ -60,12 +61,21 @@ int mi_lock_database(MI_INFO *info, int lock_type)
       else
 	count= --share->w_locks;
       --share->tot_locks;
+      /*
+         During a key cache reassignment the current and registered
+         key caches for the table are different.
+      */ 
       if (info->lock_type == F_WRLCK && !share->w_locks &&
-	  !share->delay_key_write && flush_key_blocks(share->kfile,FLUSH_KEEP))
+	  ((switch_fl= share->keycache != share->reg_keycache) ||
+           !share->delay_key_write) && 
+           flush_key_blocks(*share->keycache, share->kfile,
+                            switch_fl ? FLUSH_REMOVE : FLUSH_KEEP))
       {
 	error=my_errno;
 	mi_mark_crashed(info);		/* Mark that table must be checked */
       }
+      if (switch_fl)
+        share->keycache= share->reg_keycache;
       if (info->opt_flag & (READ_CACHE_USED | WRITE_CACHE_USED))
       {
 	if (end_io_cache(&info->rec_cache))
@@ -400,7 +410,7 @@ int _mi_test_if_changed(register MI_INFO *info)
   {						/* Keyfile has changed */
     DBUG_PRINT("info",("index file changed"));
     if (share->state.process != share->this_process)
-      VOID(flush_key_blocks(share->kfile,FLUSH_RELEASE));
+      VOID(flush_key_blocks(*share->keycache,share->kfile,FLUSH_RELEASE));
     share->last_process=share->state.process;
     info->last_unique=	share->state.unique;
     info->last_loop=	share->state.update_count;

myisam/mi_page.c

@@ -24,14 +24,16 @@
 	/* Fetch a key-page in memory */
 
 uchar *_mi_fetch_keypage(register MI_INFO *info, MI_KEYDEF *keyinfo,
-			 my_off_t page, uchar *buff, int return_buffer)
+			 my_off_t page, int level, 
+                         uchar *buff, int return_buffer)
 {
   uchar *tmp;
   uint page_size;
   DBUG_ENTER("_mi_fetch_keypage");
   DBUG_PRINT("enter",("page: %ld",page));
 
-  tmp=(uchar*) key_cache_read(info->s->kfile,page,(byte*) buff,
+  tmp=(uchar*) key_cache_read(*info->s->keycache,
+                             info->s->kfile, page, level, (byte*) buff,
 			     (uint) keyinfo->block_length,
 			     (uint) keyinfo->block_length,
 			     return_buffer);
@@ -61,7 +63,7 @@ uchar *_mi_fetch_keypage(register MI_INFO *info, MI_KEYDEF *keyinfo,
 	/* Write a key-page on disk */
 
 int _mi_write_keypage(register MI_INFO *info, register MI_KEYDEF *keyinfo,
-		      my_off_t page, uchar *buff)
+		      my_off_t page, int level, uchar *buff)
 {
   reg3 uint length;
   DBUG_ENTER("_mi_write_keypage");
@@ -92,7 +94,8 @@ int _mi_write_keypage(register MI_INFO *info, register MI_KEYDEF *keyinfo,
     length=keyinfo->block_length;
   }
 #endif
-  DBUG_RETURN((key_cache_write(info->s->kfile,page,(byte*) buff,length,
+  DBUG_RETURN((key_cache_write(*info->s->keycache,
+                         info->s->kfile,page, level, (byte*) buff,length,
 			 (uint) keyinfo->block_length,
 			 (int) ((info->lock_type != F_UNLCK) ||
 				info->s->delay_key_write))));
@@ -101,7 +104,8 @@ int _mi_write_keypage(register MI_INFO *info, register MI_KEYDEF *keyinfo,
 
 	/* Remove page from disk */
 
-int _mi_dispose(register MI_INFO *info, MI_KEYDEF *keyinfo, my_off_t pos)
+int _mi_dispose(register MI_INFO *info, MI_KEYDEF *keyinfo, my_off_t pos,
+                int level)
 {
   my_off_t old_link;
   char buff[8];
@@ -112,7 +116,8 @@ int _mi_dispose(register MI_INFO *info, MI_KEYDEF *keyinfo, my_off_t pos)
   info->s->state.key_del[keyinfo->block_size]=pos;
   mi_sizestore(buff,old_link);
   info->s->state.changed|= STATE_NOT_SORTED_PAGES;
-  DBUG_RETURN(key_cache_write(info->s->kfile,pos,buff,
+  DBUG_RETURN(key_cache_write(*info->s->keycache,
+                              info->s->kfile, pos , level, buff,
 			      sizeof(buff),
 			      (uint) keyinfo->block_length,
 			      (int) (info->lock_type != F_UNLCK)));
@@ -121,7 +126,7 @@ int _mi_dispose(register MI_INFO *info, MI_KEYDEF *keyinfo, my_off_t pos)
 
 	/* Make new page on disk */
 
-my_off_t _mi_new(register MI_INFO *info, MI_KEYDEF *keyinfo)
+my_off_t _mi_new(register MI_INFO *info, MI_KEYDEF *keyinfo, int level)
 {
   my_off_t pos;
   char buff[8];
@@ -140,7 +145,8 @@ my_off_t _mi_new(register MI_INFO *info, MI_KEYDEF *keyinfo)
   }
   else
   {
-    if (!key_cache_read(info->s->kfile,pos,
+    if (!key_cache_read(*info->s->keycache,
+                        info->s->kfile, pos, level,
 			buff,
 			(uint) sizeof(buff),
 			(uint) keyinfo->block_length,0))

myisam/mi_panic.c

@@ -48,7 +48,7 @@ int mi_panic(enum ha_panic_function flag)
       if (info->s->options & HA_OPTION_READ_ONLY_DATA)
 	break;
 #endif
-      if (flush_key_blocks(info->s->kfile,FLUSH_RELEASE))
+      if (flush_key_blocks(*info->s->keycache,info->s->kfile,FLUSH_RELEASE))
 	error=my_errno;
       if (info->opt_flag & WRITE_CACHE_USED)
 	if (flush_io_cache(&info->rec_cache))

myisam/mi_preload.c

@@ -69,7 +69,7 @@ int mi_preload(MI_INFO *info, ulonglong key_map, my_bool ignore_leaves)
   if (!(buff= (uchar *) my_malloc(length, MYF(MY_WME))))
     DBUG_RETURN(my_errno= HA_ERR_OUT_OF_MEM);
 
-  if (flush_key_blocks(share->kfile, FLUSH_RELEASE))
+  if (flush_key_blocks(*share->keycache,share->kfile, FLUSH_RELEASE))
     goto err;
  
   do
@@ -87,7 +87,9 @@ int mi_preload(MI_INFO *info, ulonglong key_map, my_bool ignore_leaves)
       {
         if (mi_test_if_nod(buff))
         {
-          if (key_cache_insert(share->kfile, pos, (byte*) buff, block_length))
+          if (key_cache_insert(*share->keycache,
+                               share->kfile, pos, DFLT_INIT_HITS, 
+                              (byte*) buff, block_length))
 	    goto err;
 	}
         pos+= block_length;
@@ -97,7 +99,9 @@ int mi_preload(MI_INFO *info, ulonglong key_map, my_bool ignore_leaves)
     }
     else
     {
-      if (key_cache_insert(share->kfile, pos, (byte*) buff, length))
+      if (key_cache_insert(*share->keycache,
+                           share->kfile, pos, DFLT_INIT_HITS,
+                           (byte*) buff, length))
 	goto err;
       pos+= length;
     }

myisam/mi_range.c

@@ -142,7 +142,7 @@ static double _mi_search_pos(register MI_INFO *info,
   if (pos == HA_OFFSET_ERROR)
     DBUG_RETURN(0.5);
 
-  if (!(buff=_mi_fetch_keypage(info,keyinfo,pos,info->buff,1)))
+  if (!(buff=_mi_fetch_keypage(info,keyinfo,pos,DFLT_INIT_HITS,info->buff,1)))
     goto err;
   flag=(*keyinfo->bin_search)(info,keyinfo,buff,key,key_len,nextflag,
 			      &keypos,info->lastkey, &after_key);

myisam/mi_search.c

@@ -76,7 +76,7 @@ int _mi_search(register MI_INFO *info, register MI_KEYDEF *keyinfo,
     DBUG_RETURN(1);                             /* Search at upper levels */
   }
 
-  if (!(buff=_mi_fetch_keypage(info,keyinfo,pos,info->buff,
+  if (!(buff=_mi_fetch_keypage(info,keyinfo,pos,DFLT_INIT_HITS,info->buff,
                                test(!(nextflag & SEARCH_SAVE_BUFF)))))
     goto err;
   DBUG_DUMP("page",(byte*) buff,mi_getint(buff));
@@ -119,7 +119,7 @@ int _mi_search(register MI_INFO *info, register MI_KEYDEF *keyinfo,
   if (pos != info->last_keypage)
   {
     uchar *old_buff=buff;
-    if (!(buff=_mi_fetch_keypage(info,keyinfo,pos,info->buff,
+    if (!(buff=_mi_fetch_keypage(info,keyinfo,pos,DFLT_INIT_HITS,info->buff,
                                  test(!(nextflag & SEARCH_SAVE_BUFF)))))
       goto err;
     keypos=buff+(keypos-old_buff);
@@ -1108,7 +1108,7 @@ int _mi_search_next(register MI_INFO *info, register MI_KEYDEF *keyinfo,
   if (info->buff_used)
   {
     if (!_mi_fetch_keypage(info,keyinfo,info->last_search_keypage,
-                           info->buff,0))
+                           DFLT_INIT_HITS,info->buff,0))
       DBUG_RETURN(-1);
     info->buff_used=0;
   }
@@ -1177,7 +1177,7 @@ int _mi_search_first(register MI_INFO *info, register MI_KEYDEF *keyinfo,
 
   do
   {
-    if (!_mi_fetch_keypage(info,keyinfo,pos,info->buff,0))
+    if (!_mi_fetch_keypage(info,keyinfo,pos,DFLT_INIT_HITS,info->buff,0))
     {
       info->lastpos= HA_OFFSET_ERROR;
       DBUG_RETURN(-1);
@@ -1220,7 +1220,7 @@ int _mi_search_last(register MI_INFO *info, register MI_KEYDEF *keyinfo,
   buff=info->buff;
   do
   {
-    if (!_mi_fetch_keypage(info,keyinfo,pos,buff,0))
+    if (!_mi_fetch_keypage(info,keyinfo,pos,DFLT_INIT_HITS,buff,0))
     {
       info->lastpos= HA_OFFSET_ERROR;
       DBUG_RETURN(-1);

myisam/mi_test1.c

@@ -50,7 +50,7 @@ int main(int argc,char *argv[])
   MY_INIT(argv[0]);
   my_init();
   if (key_cacheing)
-    init_key_cache(IO_SIZE*16);
+    init_key_cache(dflt_keycache,512,IO_SIZE*16,0);
   get_options(argc,argv);
 
   exit(run_test("test1"));

myisam/mi_test2.c

@@ -49,6 +49,7 @@ static	int verbose=0,testflag=0,
 static int pack_seg=HA_SPACE_PACK,pack_type=HA_PACK_KEY,remove_count=-1,
 	   create_flag=0;
 static ulong key_cache_size=IO_SIZE*16;
+static uint key_cache_block_size=IO_SIZE;
 
 static uint keys=MYISAM_KEYS,recant=1000;
 static uint use_blob=0;
@@ -214,7 +215,7 @@ int main(int argc, char *argv[])
   if (!silent)
     printf("- Writing key:s\n");
   if (key_cacheing)
-    init_key_cache(key_cache_size);		/* Use a small cache */
+    init_key_cache(dflt_keycache,key_cache_block_size,key_cache_size,0);		/* Use a small cache */
   if (locking)
     mi_lock_database(file,F_WRLCK);
   if (write_cacheing)
@@ -274,7 +275,7 @@ int main(int argc, char *argv[])
       goto end;
     }
     if (key_cacheing)
-      resize_key_cache(key_cache_size*2);
+      resize_key_cache(dflt_keycache,key_cache_block_size,key_cache_size*2);
   }
 
   if (!silent)
@@ -816,16 +817,19 @@ end:
       puts("Locking used");
     if (use_blob)
       puts("blobs used");
+#if 0
     printf("key cache status: \n\
 blocks used:%10lu\n\
 w_requests: %10lu\n\
 writes:     %10lu\n\
 r_requests: %10lu\n\
 reads:      %10lu\n",
-	   my_blocks_used, my_cache_w_requests, my_cache_write,
+	   my_blocks_used,
+           my_cache_w_requests, my_cache_write,
 	   my_cache_r_requests, my_cache_read);
+#endif
   }
-  end_key_cache();
+  end_key_cache(dflt_keycache,1);
   if (blob_buffer)
     my_free(blob_buffer,MYF(0));
   my_end(silent ? MY_CHECK_ERROR : MY_CHECK_ERROR | MY_GIVE_INFO);

myisam/mi_test3.c

@@ -177,7 +177,7 @@ void start_test(int id)
     exit(1);
   }
   if (key_cacheing && rnd(2) == 0)
-    init_key_cache(65536L);
+    init_key_cache(dflt_keycache,512,65536L,0);
   printf("Process %d, pid: %d\n",id,getpid()); fflush(stdout);
 
   for (error=i=0 ; i < tests && !error; i++)

myisam/mi_write.c

@@ -290,8 +290,8 @@ int _mi_enlarge_root(MI_INFO *info, MI_KEYDEF *keyinfo, uchar *key,
   mi_putint(info->buff,t_length+2+nod_flag,nod_flag);
   (*keyinfo->store_key)(keyinfo,info->buff+2+nod_flag,&s_temp);
   info->buff_used=info->page_changed=1;		/* info->buff is used */
-  if ((*root= _mi_new(info,keyinfo)) == HA_OFFSET_ERROR ||
-      _mi_write_keypage(info,keyinfo,*root,info->buff))
+  if ((*root= _mi_new(info,keyinfo,DFLT_INIT_HITS)) == HA_OFFSET_ERROR ||
+      _mi_write_keypage(info,keyinfo,*root,DFLT_INIT_HITS,info->buff))
     DBUG_RETURN(-1);
   DBUG_RETURN(0);
 } /* _mi_enlarge_root */
@@ -322,7 +322,7 @@ static int w_search(register MI_INFO *info, register MI_KEYDEF *keyinfo,
   if (!(temp_buff= (uchar*) my_alloca((uint) keyinfo->block_length+
 				      MI_MAX_KEY_BUFF*2)))
     DBUG_RETURN(-1);
-  if (!_mi_fetch_keypage(info,keyinfo,page,temp_buff,0))
+  if (!_mi_fetch_keypage(info,keyinfo,page,DFLT_INIT_HITS,temp_buff,0))
     goto err;
 
   flag=(*keyinfo->bin_search)(info,keyinfo,temp_buff,key,search_key_length,
@@ -368,7 +368,7 @@ static int w_search(register MI_INFO *info, register MI_KEYDEF *keyinfo,
         subkeys--; /* should there be underflow protection ? */
         ft_intXstore(keypos, subkeys);
         if (!error)
-          error=_mi_write_keypage(info,keyinfo,page,temp_buff);
+          error=_mi_write_keypage(info,keyinfo,page,DFLT_INIT_HITS,temp_buff);
         my_afree((byte*) temp_buff);
         DBUG_RETURN(error);
       }
@@ -391,7 +391,7 @@ static int w_search(register MI_INFO *info, register MI_KEYDEF *keyinfo,
   {
     error=_mi_insert(info,keyinfo,key,temp_buff,keypos,keybuff,father_buff,
 		     father_keypos,father_page, insert_last);
-    if (_mi_write_keypage(info,keyinfo,page,temp_buff))
+    if (_mi_write_keypage(info,keyinfo,page,DFLT_INIT_HITS,temp_buff))
       goto err;
   }
   my_afree((byte*) temp_buff);
@@ -515,7 +515,7 @@ int _mi_split_page(register MI_INFO *info, register MI_KEYDEF *keyinfo,
   }
 
 	/* Move middle item to key and pointer to new page */
-  if ((new_pos=_mi_new(info,keyinfo)) == HA_OFFSET_ERROR)
+  if ((new_pos=_mi_new(info,keyinfo,DFLT_INIT_HITS)) == HA_OFFSET_ERROR)
     DBUG_RETURN(-1);
   _mi_kpointer(info,_mi_move_key(keyinfo,key,key_buff),new_pos);
 
@@ -531,7 +531,7 @@ int _mi_split_page(register MI_INFO *info, register MI_KEYDEF *keyinfo,
   (*keyinfo->store_key)(keyinfo,info->buff+key_ref_length,&s_temp);
   mi_putint(info->buff,length+t_length+key_ref_length,nod_flag);
 
-  if (_mi_write_keypage(info,keyinfo,new_pos,info->buff))
+  if (_mi_write_keypage(info,keyinfo,new_pos,DFLT_INIT_HITS,info->buff))
     DBUG_RETURN(-1);
   DBUG_DUMP("key",(byte*) key,_mi_keylength(keyinfo,key));
   DBUG_RETURN(2);				/* Middle key up */
@@ -682,7 +682,7 @@ static int _mi_balance_page(register MI_INFO *info, MI_KEYDEF *keyinfo,
     DBUG_PRINT("test",("use left page: %lu",next_page));
   }					/* father_key_pos ptr to parting key */
 
-  if (!_mi_fetch_keypage(info,keyinfo,next_page,info->buff,0))
+  if (!_mi_fetch_keypage(info,keyinfo,next_page,DFLT_INIT_HITS,info->buff,0))
     goto err;
   DBUG_DUMP("next",(byte*) info->buff,mi_getint(info->buff));
 
@@ -722,8 +722,8 @@ static int _mi_balance_page(register MI_INFO *info, MI_KEYDEF *keyinfo,
       memcpy((byte*) buff+2,(byte*) pos+k_length,(size_t) length);
     }
 
-    if (_mi_write_keypage(info,keyinfo,next_page,info->buff) ||
-	_mi_write_keypage(info,keyinfo,father_page,father_buff))
+    if (_mi_write_keypage(info,keyinfo,next_page,DFLT_INIT_HITS,info->buff) ||
+	_mi_write_keypage(info,keyinfo,father_page,DFLT_INIT_HITS,father_buff))
       goto err;
     DBUG_RETURN(0);
   }
@@ -763,12 +763,13 @@ static int _mi_balance_page(register MI_INFO *info, MI_KEYDEF *keyinfo,
   memcpy((byte*) (right ? key : father_key_pos),pos,(size_t) k_length);
   memcpy((byte*) (right ? father_key_pos : key),tmp_part_key, k_length);
 
-  if ((new_pos=_mi_new(info,keyinfo)) == HA_OFFSET_ERROR)
+  if ((new_pos=_mi_new(info,keyinfo,DFLT_INIT_HITS)) == HA_OFFSET_ERROR)
     goto err;
   _mi_kpointer(info,key+k_length,new_pos);
   if (_mi_write_keypage(info,keyinfo,(right ? new_pos : next_page),
-			info->buff) ||
-      _mi_write_keypage(info,keyinfo,(right ? next_page : new_pos),extra_buff))
+			DFLT_INIT_HITS,info->buff) ||
+      _mi_write_keypage(info,keyinfo,(right ? next_page : new_pos),
+                        DFLT_INIT_HITS,extra_buff))
     goto err;
 
   DBUG_RETURN(1);				/* Middle key up */

myisam/myisamchk.c

@@ -44,6 +44,7 @@ static const char *load_default_groups[]= { "myisamchk", 0 };
 static const char *set_charset_name, *opt_tmpdir;
 static CHARSET_INFO *set_charset;
 static long opt_myisam_block_size;
+static long opt_key_cache_block_size;
 static const char *my_progname_short;
 static int stopwords_inited= 0;
 static MY_TMPDIR myisamchk_tmpdir;
@@ -148,7 +149,8 @@ int main(int argc, char **argv)
 
 enum options {
   OPT_CHARSETS_DIR=256, OPT_SET_CHARSET,OPT_START_CHECK_POS,
-  OPT_CORRECT_CHECKSUM, OPT_KEY_BUFFER_SIZE, OPT_MYISAM_BLOCK_SIZE,
+  OPT_CORRECT_CHECKSUM, OPT_KEY_BUFFER_SIZE,
+  OPT_KEY_CACHE_BLOCK_SIZE, OPT_MYISAM_BLOCK_SIZE,
   OPT_READ_BUFFER_SIZE, OPT_WRITE_BUFFER_SIZE, OPT_SORT_BUFFER_SIZE,
   OPT_SORT_KEY_BLOCKS, OPT_DECODE_BITS, OPT_FT_MIN_WORD_LEN,
   OPT_FT_MAX_WORD_LEN, OPT_FT_MAX_WORD_LEN_FOR_SORT
@@ -283,6 +285,11 @@ static struct my_option my_long_options[] =
     (gptr*) &check_param.use_buffers, (gptr*) &check_param.use_buffers, 0,
     GET_ULONG, REQUIRED_ARG, (long) USE_BUFFER_INIT, (long) MALLOC_OVERHEAD,
     (long) ~0L, (long) MALLOC_OVERHEAD, (long) IO_SIZE, 0},
+  { "key_cache_block_size", OPT_KEY_CACHE_BLOCK_SIZE,  "",
+    (gptr*) &opt_key_cache_block_size,
+    (gptr*) &opt_key_cache_block_size, 0,
+    GET_LONG, REQUIRED_ARG, MI_KEY_BLOCK_LENGTH, MI_MIN_KEY_BLOCK_LENGTH,
+    MI_MAX_KEY_BLOCK_LENGTH, 0, MI_MIN_KEY_BLOCK_LENGTH, 0},
   { "myisam_block_size", OPT_MYISAM_BLOCK_SIZE,  "",
     (gptr*) &opt_myisam_block_size, (gptr*) &opt_myisam_block_size, 0,
     GET_LONG, REQUIRED_ARG, MI_KEY_BLOCK_LENGTH, MI_MIN_KEY_BLOCK_LENGTH,
@@ -1025,7 +1032,8 @@ static int myisamchk(MI_CHECK *param, my_string filename)
 	  !(param->testflag & (T_FAST | T_FORCE_CREATE)))
       {
 	if (param->testflag & (T_EXTEND | T_MEDIUM))
-	  VOID(init_key_cache(param->use_buffers));
+	  VOID(init_key_cache(dflt_keycache,opt_key_cache_block_size,
+                              param->use_buffers,&dflt_key_cache_var));
 	VOID(init_io_cache(&param->read_cache,datafile,
 			   (uint) param->read_buffer_length,
 			   READ_CACHE,
@@ -1448,7 +1456,8 @@ static int mi_sort_records(MI_CHECK *param,
   if (share->state.key_root[sort_key] == HA_OFFSET_ERROR)
     DBUG_RETURN(0);				/* Nothing to do */
 
-  init_key_cache(param->use_buffers);
+  init_key_cache(dflt_keycache,opt_key_cache_block_size,param->use_buffers,
+                 &dflt_key_cache_var);
   if (init_io_cache(&info->rec_cache,-1,(uint) param->write_buffer_length,
 		   WRITE_CACHE,share->pack.header_length,1,
 		   MYF(MY_WME | MY_WAIT_IF_FULL)))

myisam/myisamdef.h

@@ -166,6 +166,8 @@ typedef struct st_mi_isam_share {	/* Shared between opens */
   char  *data_file_name,		/* Resolved path names from symlinks */
         *index_file_name;
   byte *file_map;			/* mem-map of file if possible */
+  KEY_CACHE_HANDLE *keycache;           /* ref to the current key cache */
+  KEY_CACHE_HANDLE *reg_keycache;       /* ref to the registered key cache */
   MI_DECODE_TREE *decode_trees;
   uint16 *decode_tables;
   int (*read_record)(struct st_myisam_info*, my_off_t, byte*);
@@ -546,11 +548,12 @@ extern int _mi_search_next(MI_INFO *info,MI_KEYDEF *keyinfo,uchar *key,
 extern int _mi_search_first(MI_INFO *info,MI_KEYDEF *keyinfo,my_off_t pos);
 extern int _mi_search_last(MI_INFO *info,MI_KEYDEF *keyinfo,my_off_t pos);
 extern uchar *_mi_fetch_keypage(MI_INFO *info,MI_KEYDEF *keyinfo,my_off_t page,
-				uchar *buff,int return_buffer);
+				int level,uchar *buff,int return_buffer);
 extern int _mi_write_keypage(MI_INFO *info,MI_KEYDEF *keyinfo,my_off_t page,
-			     uchar *buff);
-extern int _mi_dispose(MI_INFO *info,MI_KEYDEF *keyinfo,my_off_t pos);
-extern my_off_t _mi_new(MI_INFO *info,MI_KEYDEF *keyinfo);
+			     int level, uchar *buff);
+extern int _mi_dispose(MI_INFO *info,MI_KEYDEF *keyinfo,my_off_t pos,
+                      int level);
+extern my_off_t _mi_new(MI_INFO *info,MI_KEYDEF *keyinfo,int level);
 extern uint _mi_make_key(MI_INFO *info,uint keynr,uchar *key,
 			 const byte *record,my_off_t filepos);
 extern uint _mi_pack_key(MI_INFO *info,uint keynr,uchar *key,uchar *old,

myisam/myisamlog.c

@@ -333,7 +333,8 @@ static int examine_log(my_string file_name, char **table_names)
   bzero((gptr) com_count,sizeof(com_count));
   init_tree(&tree,0,0,sizeof(file_info),(qsort_cmp2) file_info_compare,1,
 	    (tree_element_free) file_info_free, NULL);
-  VOID(init_key_cache(KEY_CACHE_SIZE));
+  VOID(init_key_cache(dflt_keycache,KEY_CACHE_BLOCK_SIZE,KEY_CACHE_SIZE,
+                      &dflt_key_cache_var));
 
   files_open=0; access_time=0;
   while (access_time++ != number_of_commands &&
@@ -647,7 +648,7 @@ static int examine_log(my_string file_name, char **table_names)
       goto end;
     }
   }
-  end_key_cache();
+  end_key_cache(dflt_keycache,1);
   delete_tree(&tree);
   VOID(end_io_cache(&cache));
   VOID(my_close(file,MYF(0)));
@@ -667,7 +668,7 @@ static int examine_log(my_string file_name, char **table_names)
 	       llstr(isamlog_filepos,llbuff)));
   fflush(stderr);
  end:
-  end_key_cache();
+  end_key_cache(dflt_keycache,1);
   delete_tree(&tree);
   VOID(end_io_cache(&cache));
   VOID(my_close(file,MYF(0)));

myisam/rt_index.c

@@ -60,7 +60,7 @@ static int rtree_find_req(MI_INFO *info, MI_KEYDEF *keyinfo, uint search_flag, u
     my_errno = HA_ERR_OUT_OF_MEM;
     return -1;
   }
-  if (!_mi_fetch_keypage(info, keyinfo, page, page_buf, 0))
+  if (!_mi_fetch_keypage(info, keyinfo, page, DFLT_INIT_HITS, page_buf, 0))
     goto err1;
   nod_flag = mi_test_if_nod(page_buf);
 
@@ -257,7 +257,7 @@ static int rtree_get_req(MI_INFO *info, MI_KEYDEF *keyinfo, uint key_length,
   
   if (!(page_buf = (uchar*)my_alloca((uint)keyinfo->block_length)))
     return -1;
-  if (!_mi_fetch_keypage(info, keyinfo, page, page_buf, 0))
+  if (!_mi_fetch_keypage(info, keyinfo, page, DFLT_INIT_HITS, page_buf, 0))
     goto err1;
   nod_flag = mi_test_if_nod(page_buf);
 
@@ -429,7 +429,7 @@ static int rtree_insert_req(MI_INFO *info, MI_KEYDEF *keyinfo, uchar *key,
     my_errno = HA_ERR_OUT_OF_MEM;
     return -1;
   }
-  if (!_mi_fetch_keypage(info, keyinfo, page, page_buf, 0))
+  if (!_mi_fetch_keypage(info, keyinfo, page, DFLT_INIT_HITS, page_buf, 0))
     goto err1;
   nod_flag = mi_test_if_nod(page_buf);
 
@@ -445,7 +445,7 @@ static int rtree_insert_req(MI_INFO *info, MI_KEYDEF *keyinfo, uchar *key,
       case 0: /* child was not split */
       {
         rtree_combine_rect(keyinfo->seg, k, key, k, key_length);
-        if (_mi_write_keypage(info, keyinfo, page, page_buf))
+        if (_mi_write_keypage(info, keyinfo, page, DFLT_INIT_HITS, page_buf))
           goto err1;
         goto ok;
       }
@@ -462,7 +462,7 @@ static int rtree_insert_req(MI_INFO *info, MI_KEYDEF *keyinfo, uchar *key,
           goto err1;
         res = rtree_add_key(info, keyinfo, new_key, key_length, 
                            page_buf, new_page);
-        if (_mi_write_keypage(info, keyinfo, page, page_buf))
+        if (_mi_write_keypage(info, keyinfo, page, DFLT_INIT_HITS, page_buf))
           goto err1;
         goto ok;
       }
@@ -476,7 +476,7 @@ static int rtree_insert_req(MI_INFO *info, MI_KEYDEF *keyinfo, uchar *key,
   else
   { 
     res = rtree_add_key(info, keyinfo, key, key_length, page_buf, new_page);
-    if (_mi_write_keypage(info, keyinfo, page, page_buf))
+    if (_mi_write_keypage(info, keyinfo, page, DFLT_INIT_HITS, page_buf))
       goto err1;
     goto ok;
   }
@@ -509,12 +509,12 @@ static int rtree_insert_level(MI_INFO *info, uint keynr, uchar *key,
   {
     int res;
 
-    if ((old_root = _mi_new(info, keyinfo)) == HA_OFFSET_ERROR)
+    if ((old_root = _mi_new(info, keyinfo, DFLT_INIT_HITS)) == HA_OFFSET_ERROR)
       return -1;
     info->buff_used = 1;
     mi_putint(info->buff, 2, 0);
     res = rtree_add_key(info, keyinfo, key, key_length, info->buff, NULL);
-    if (_mi_write_keypage(info, keyinfo, old_root, info->buff))
+    if (_mi_write_keypage(info, keyinfo, old_root, DFLT_INIT_HITS, info->buff))
       return 1;
     info->s->state.key_root[keynr] = old_root;
     return res;
@@ -542,7 +542,8 @@ static int rtree_insert_level(MI_INFO *info, uint keynr, uchar *key,
       }
 
       mi_putint(new_root_buf, 2, nod_flag);
-      if ((new_root = _mi_new(info, keyinfo)) == HA_OFFSET_ERROR)
+      if ((new_root = _mi_new(info, keyinfo, DFLT_INIT_HITS)) ==
+                                                             HA_OFFSET_ERROR)
         goto err1;
 
       new_key = new_root_buf + keyinfo->block_length + nod_flag;
@@ -559,7 +560,8 @@ static int rtree_insert_level(MI_INFO *info, uint keynr, uchar *key,
       if (rtree_add_key(info, keyinfo, new_key, key_length, new_root_buf, NULL) 
           == -1)
         goto err1;
-      if (_mi_write_keypage(info, keyinfo, new_root, new_root_buf))
+      if (_mi_write_keypage(info, keyinfo, new_root,
+                            DFLT_INIT_HITS, new_root_buf))
         goto err1;
       info->s->state.key_root[keynr] = new_root;
 
@@ -636,7 +638,7 @@ static int rtree_delete_req(MI_INFO *info, MI_KEYDEF *keyinfo, uchar *key,
     my_errno = HA_ERR_OUT_OF_MEM;
     return -1;
   }
-  if (!_mi_fetch_keypage(info, keyinfo, page, page_buf, 0))
+  if (!_mi_fetch_keypage(info, keyinfo, page, DFLT_INIT_HITS, page_buf, 0))
     goto err1;
   nod_flag = mi_test_if_nod(page_buf);
 
@@ -662,7 +664,8 @@ static int rtree_delete_req(MI_INFO *info, MI_KEYDEF *keyinfo, uchar *key,
               if (rtree_set_key_mbr(info, keyinfo, k, key_length, 
                                   _mi_kpos(nod_flag, k)))
                 goto err1;
-              if (_mi_write_keypage(info, keyinfo, page, page_buf))
+              if (_mi_write_keypage(info, keyinfo, page,
+                                    DFLT_INIT_HITS, page_buf))
                 goto err1;
             }
             else
@@ -672,7 +675,8 @@ static int rtree_delete_req(MI_INFO *info, MI_KEYDEF *keyinfo, uchar *key,
                                            level + 1))
                 goto err1;
               rtree_delete_key(info, page_buf, k, key_length, nod_flag);
-              if (_mi_write_keypage(info, keyinfo, page, page_buf))
+              if (_mi_write_keypage(info, keyinfo, page,
+                                    DFLT_INIT_HITS, page_buf))
                 goto err1;
               *page_size = mi_getint(page_buf);
             }
@@ -686,7 +690,8 @@ static int rtree_delete_req(MI_INFO *info, MI_KEYDEF *keyinfo, uchar *key,
           case 2: /* vacuous case: last key in the leaf */
           {
             rtree_delete_key(info, page_buf, k, key_length, nod_flag);
-            if (_mi_write_keypage(info, keyinfo, page, page_buf))
+            if (_mi_write_keypage(info, keyinfo, page,
+                                  DFLT_INIT_HITS, page_buf))
               goto err1;
             *page_size = mi_getint(page_buf);
             res = 0;
@@ -711,13 +716,13 @@ static int rtree_delete_req(MI_INFO *info, MI_KEYDEF *keyinfo, uchar *key,
         {
           /* last key in the leaf */
           res = 2;
-          if (_mi_dispose(info, keyinfo, page))
+          if (_mi_dispose(info, keyinfo, page, DFLT_INIT_HITS))
             goto err1;
         }
         else
         {
           res = 0;
-          if (_mi_write_keypage(info, keyinfo, page, page_buf))
+          if (_mi_write_keypage(info, keyinfo, page, DFLT_INIT_HITS, page_buf))
             goto err1;
         }
         goto ok;
@@ -783,7 +788,7 @@ int rtree_delete(MI_INFO *info, uint keynr, uchar *key, uint key_length)
           goto err1;
         }
         if (!_mi_fetch_keypage(info, keyinfo, ReinsertList.pages[i].offs, 
-                               page_buf, 0))
+                               DFLT_INIT_HITS, page_buf, 0))
           goto err1;
         nod_flag = mi_test_if_nod(page_buf);
         k = rt_PAGE_FIRST_KEY(page_buf, nod_flag);
@@ -798,7 +803,8 @@ int rtree_delete(MI_INFO *info, uint keynr, uchar *key, uint key_length)
           }
         }
         my_afree((byte*)page_buf);
-        if (_mi_dispose(info, keyinfo, ReinsertList.pages[i].offs))
+        if (_mi_dispose(info, keyinfo, ReinsertList.pages[i].offs,
+            DFLT_INIT_HITS))
           goto err1;
       }
       if (ReinsertList.pages)
@@ -807,7 +813,8 @@ int rtree_delete(MI_INFO *info, uint keynr, uchar *key, uint key_length)
       /* check for redundant root (not leaf, 1 child) and eliminate */
       if ((old_root = info->s->state.key_root[keynr]) == HA_OFFSET_ERROR)
         goto err1;
-      if (!_mi_fetch_keypage(info, keyinfo, old_root, info->buff, 0))
+      if (!_mi_fetch_keypage(info, keyinfo, old_root, DFLT_INIT_HITS, 
+                             info->buff, 0))
         goto err1;
       nod_flag = mi_test_if_nod(info->buff);
       page_size = mi_getint(info->buff);
@@ -816,7 +823,7 @@ int rtree_delete(MI_INFO *info, uint keynr, uchar *key, uint key_length)
       {
         my_off_t new_root = _mi_kpos(nod_flag, 
                                      rt_PAGE_FIRST_KEY(info->buff, nod_flag));
-        if (_mi_dispose(info, keyinfo, old_root))
+        if (_mi_dispose(info, keyinfo, old_root, DFLT_INIT_HITS))
           goto err1;
         info->s->state.key_root[keynr] = new_root;
       }
@@ -863,7 +870,7 @@ ha_rows rtree_estimate(MI_INFO *info, uint keynr, uchar *key,
     return HA_POS_ERROR;
   if (!(page_buf = (uchar*)my_alloca((uint)keyinfo->block_length)))
     return HA_POS_ERROR;
-  if (!_mi_fetch_keypage(info, keyinfo, root, page_buf, 0))
+  if (!_mi_fetch_keypage(info, keyinfo, root, DFLT_INIT_HITS, page_buf, 0))
     goto err1;
   nod_flag = mi_test_if_nod(page_buf);
 

myisam/rt_key.c

@@ -88,7 +88,8 @@ int rtree_delete_key(MI_INFO *info, uchar *page_buf, uchar *key,
 int rtree_set_key_mbr(MI_INFO *info, MI_KEYDEF *keyinfo, uchar *key, 
 		      uint key_length, my_off_t child_page)
 {
-  if (!_mi_fetch_keypage(info, keyinfo, child_page, info->buff, 0))
+  if (!_mi_fetch_keypage(info, keyinfo, child_page,
+                         DFLT_INIT_HITS, info->buff, 0))
     return -1;
 
   return rtree_page_mbr(info, keyinfo->seg, info->buff, key, key_length);

myisam/rt_split.c

@@ -332,10 +332,12 @@ int rtree_split_page(MI_INFO *info, MI_KEYDEF *keyinfo, uchar *page, uchar *key,
   mi_putint(page, 2 + n1 * full_length, nod_flag);
   mi_putint(new_page, 2 + n2 * full_length, nod_flag);
 
-  if ((*new_page_offs= _mi_new(info, keyinfo)) == HA_OFFSET_ERROR)
+  if ((*new_page_offs= _mi_new(info, keyinfo, DFLT_INIT_HITS)) == 
+                                                               HA_OFFSET_ERROR)
     err_code= -1;
   else
-    err_code= _mi_write_keypage(info, keyinfo, *new_page_offs, new_page);
+    err_code= _mi_write_keypage(info, keyinfo, *new_page_offs,
+                                DFLT_INIT_HITS, new_page);
 
   my_afree((byte*)new_page);
 

mysql-test/r/func_group.result

@@ -514,7 +514,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 explain 
 select min(a1) from t1 where a1 != 'KKK';
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	index	NULL	PRIMARY	3	NULL	14	Using where; Using index
+1	SIMPLE	t1	range	PRIMARY	PRIMARY	3	NULL	14	Using where; Using index
 explain
 select max(a3) from t1 where a2 < 2 and a3 < 'SEA';
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
@@ -560,7 +560,7 @@ explain
 select concat(min(t1.a1),min(t2.a4)) from t1, t2 where t2.a4 <> 'AME';
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	index	NULL	PRIMARY	3	NULL	14	Using index
-1	SIMPLE	t2	index	NULL	k2	4	NULL	6	Using where; Using index
+1	SIMPLE	t2	range	k2	k2	4	NULL	6	Using where; Using index
 drop table t1, t2;
 CREATE TABLE t1 (a int, b int);
 select count(b), sum(b), avg(b), std(b), min(b), max(b), bit_and(b), bit_or(b) from t1;

mysql-test/r/key_cache.result

@@ -41,3 +41,194 @@ SELECT @@default.key_buffer_size;
 ERROR 42000: You have an error in your SQL syntax.  Check the manual that corresponds to your MySQL server version for the right syntax to use near 'default.key_buffer_size' at line 1
 SELECT @@skr.table_type="test";
 ERROR HY000: Variable 'table_type' is not a variable component (Can't be used as XXXX.variable_name)
+select @@keycache1.key_cache_block_size;
+@@keycache1.key_cache_block_size
+0
+select @@keycache1.key_buffer_size;
+@@keycache1.key_buffer_size
+0
+set global keycache1.key_cache_block_size=2048;
+select @@keycache1.key_buffer_size;
+@@keycache1.key_buffer_size
+0
+select @@keycache1.key_cache_block_size;
+@@keycache1.key_cache_block_size
+2048
+set global keycache1.key_buffer_size=1*1024*1024;
+select @@keycache1.key_buffer_size;
+@@keycache1.key_buffer_size
+1048576
+select @@keycache1.key_cache_block_size;
+@@keycache1.key_cache_block_size
+2048
+set global keycache2.key_buffer_size=4*1024*1024;
+select @@keycache2.key_buffer_size;
+@@keycache2.key_buffer_size
+4194304
+select @@keycache2.key_cache_block_size;
+@@keycache2.key_cache_block_size
+1024
+set global keycache1.key_buffer_size=0;
+select @@keycache1.key_buffer_size;
+@@keycache1.key_buffer_size
+0
+select @@keycache1.key_cache_block_size;
+@@keycache1.key_cache_block_size
+0
+select @@key_buffer_size;
+@@key_buffer_size
+2097152
+select @@key_cache_block_size;
+@@key_cache_block_size
+1024
+drop table if exists t1, t2;
+create table t1 (p int primary key, a char(10));
+create table t2 (p int primary key, i int, a char(10), key k1(i), key k2(a));
+insert into t1 values (1, 'qqqq'), (11, 'yyyy');
+insert into t2 values (1, 1, 'qqqq'), (2, 1, 'pppp'),
+(3, 1, 'yyyy'), (4, 3, 'zzzz');
+select * from t1;
+p	a
+1	qqqq
+11	yyyy
+select * from t2;
+p	i	a
+1	1	qqqq
+2	1	pppp
+3	1	yyyy
+4	3	zzzz
+update t1 set p=2 where p=1;
+update t2 set i=2 where i=1;
+cache index t1 keys in keycache1;
+Table	Op	Msg_type	Msg_text
+test.t1	assign_to_keycache	status	OK
+explain select p from t1;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	index	NULL	PRIMARY	4	NULL	2	Using index
+select p from t1;
+p
+2
+11
+explain select i from t2;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	index	NULL	k1	5	NULL	4	Using index
+select i from t2;
+i
+2
+2
+2
+3
+explain select count(*) from t1, t2 where t1.p = t2.i;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	index	PRIMARY	PRIMARY	4	NULL	2	Using index
+1	SIMPLE	t2	ref	k1	k1	5	test.t1.p	2	Using where; Using index
+select count(*) from t1, t2 where t1.p = t2.i;
+count(*)
+3
+cache index t2 keys in keycache1;
+Table	Op	Msg_type	Msg_text
+test.t2	assign_to_keycache	status	OK
+update t2 set p=p+1000, i=2 where a='qqqq';
+cache index t2 keys in keycache2;
+Table	Op	Msg_type	Msg_text
+test.t2	assign_to_keycache	status	OK
+insert into t2 values (2000, 3, 'yyyy');
+cache index t2 keys in keycache1;
+Table	Op	Msg_type	Msg_text
+test.t2	assign_to_keycache	status	OK
+update t2 set p=3000 where a='zzzz';
+select * from t2;
+p	i	a
+1001	2	qqqq
+2	2	pppp
+3	2	yyyy
+3000	3	zzzz
+2000	3	yyyy
+explain select p from t2;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	index	NULL	PRIMARY	4	NULL	5	Using index
+select p from t2;
+p
+2
+3
+1001
+2000
+3000
+explain select i from t2;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	index	NULL	k1	5	NULL	5	Using index
+select i from t2;
+i
+2
+2
+2
+3
+3
+explain select a from t2;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	index	NULL	k2	11	NULL	5	Using index
+select a from t2;
+a
+pppp
+qqqq
+yyyy
+yyyy
+zzzz
+select @@keycache2.key_buffer_size;
+@@keycache2.key_buffer_size
+4194304
+select @@keycache2.key_cache_block_size;
+@@keycache2.key_cache_block_size
+1024
+set global keycache2.key_buffer_size=0;
+select @@keycache2.key_buffer_size;
+@@keycache2.key_buffer_size
+0
+select @@keycache2.key_cache_block_size;
+@@keycache2.key_cache_block_size
+0
+update t2 set p=4000 where a='zzzz';
+update t1 set p=p+1;
+set global keycache1.key_buffer_size=0;
+select * from t2;
+p	i	a
+1001	2	qqqq
+2	2	pppp
+3	2	yyyy
+4000	3	zzzz
+2000	3	yyyy
+select p from t2;
+p
+2
+3
+1001
+2000
+4000
+explain select i from t2;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	index	NULL	k1	5	NULL	5	Using index
+select i from t2;
+i
+2
+2
+2
+3
+3
+explain select a from t2;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	index	NULL	k2	11	NULL	5	Using index
+select a from t2;
+a
+pppp
+qqqq
+yyyy
+yyyy
+zzzz
+select * from t1;
+p	a
+3	qqqq
+12	yyyy
+select p from t1;
+p
+3
+12

mysql-test/t/key_cache.test

 #
-# Test of key cache
+# Test of multiple key caches
 #
 
 SET @save_key_buffer=@@key_buffer_size;
@@ -40,3 +40,83 @@ SET @@global.key_buffer_size=@save_key_buffer;
 SELECT @@default.key_buffer_size;
 --error 1271
 SELECT @@skr.table_type="test";
+
+select @@keycache1.key_cache_block_size;
+select @@keycache1.key_buffer_size;
+set global keycache1.key_cache_block_size=2048;
+select @@keycache1.key_buffer_size;
+select @@keycache1.key_cache_block_size;
+set global keycache1.key_buffer_size=1*1024*1024;
+select @@keycache1.key_buffer_size;
+select @@keycache1.key_cache_block_size;
+set global keycache2.key_buffer_size=4*1024*1024;
+select @@keycache2.key_buffer_size;
+select @@keycache2.key_cache_block_size;
+set global keycache1.key_buffer_size=0;
+select @@keycache1.key_buffer_size;
+select @@keycache1.key_cache_block_size;
+select @@key_buffer_size;
+select @@key_cache_block_size;
+
+
+--disable_warnings
+drop table if exists t1, t2;
+--enable_warnings
+
+create table t1 (p int primary key, a char(10));
+create table t2 (p int primary key, i int, a char(10), key k1(i), key k2(a));
+
+insert into t1 values (1, 'qqqq'), (11, 'yyyy');
+insert into t2 values (1, 1, 'qqqq'), (2, 1, 'pppp'),
+                      (3, 1, 'yyyy'), (4, 3, 'zzzz');
+select * from t1;
+select * from t2;
+
+update t1 set p=2 where p=1;
+update t2 set i=2 where i=1;
+
+cache index t1 keys in keycache1;
+
+explain select p from t1;
+select p from t1;
+explain select i from t2;
+select i from t2;
+explain select count(*) from t1, t2 where t1.p = t2.i;
+select count(*) from t1, t2 where t1.p = t2.i;
+
+cache index t2 keys in keycache1;
+update t2 set p=p+1000, i=2 where a='qqqq';
+cache index t2 keys in keycache2;
+insert into t2 values (2000, 3, 'yyyy');
+cache index t2 keys in keycache1;
+update t2 set p=3000 where a='zzzz';
+select * from t2;
+explain select p from t2;
+select p from t2;
+explain select i from t2;
+select i from t2;
+explain select a from t2;
+select a from t2;
+
+select @@keycache2.key_buffer_size;
+select @@keycache2.key_cache_block_size;
+set global keycache2.key_buffer_size=0;
+select @@keycache2.key_buffer_size;
+select @@keycache2.key_cache_block_size;
+
+
+update t2 set p=4000 where a='zzzz';
+update t1 set p=p+1;
+
+set global keycache1.key_buffer_size=0;
+select * from t2;
+select p from t2;
+explain select i from t2;
+select i from t2;
+explain select a from t2;
+select a from t2;
+
+select * from t1;
+select p from t1;
+
+

sql/ha_myisam.cc

@@ -229,6 +229,12 @@ int ha_myisam::open(const char *name, int mode, uint test_if_locked)
   if (!(file=mi_open(name, mode, test_if_locked)))
     return (my_errno ? my_errno : -1);
   
+  /* Synchronize key cache assignment of the handler */ 
+  KEY_CACHE_VAR *key_cache= table->key_cache ? table->key_cache :
+                                               &dflt_key_cache_var;
+  VOID(mi_extra(file, HA_EXTRA_SET_KEY_CACHE,
+                (void*) &key_cache->cache));
+
   if (test_if_locked & (HA_OPEN_IGNORE_IF_LOCKED | HA_OPEN_TMP_TABLE))
     VOID(mi_extra(file, HA_EXTRA_NO_WAIT_LOCK, 0));
   info(HA_STATUS_NO_LOCK | HA_STATUS_VARIABLE | HA_STATUS_CONST);
@@ -691,6 +697,131 @@ int ha_myisam::repair(THD *thd, MI_CHECK &param, bool optimize)
 }
 
 
+/*
+  Assign table indexes to a key cache.
+*/
+
+int ha_myisam::assign_to_keycache(THD* thd, HA_CHECK_OPT *check_opt)
+{
+  uint len;
+  KEY_CACHE_VAR *old_key_cache;
+  KEY_CACHE_VAR *new_key_cache;                           
+  const char *errmsg=0;
+  int error= HA_ADMIN_OK;
+  ulonglong map= ~(ulonglong) 0;
+  TABLE_LIST *table_list= table->pos_in_table_list;
+  const char *new_key_cache_name= table_list->option ?
+                                  (const char *) table_list->option :
+                                  DEFAULT_KEY_CACHE_NAME;
+  KEY_CACHE_ASMT *key_cache_asmt= table->key_cache_asmt;
+  bool triggered= key_cache_asmt->triggered; 
+  
+  DBUG_ENTER("ha_myisam::assign_to_keycache");
+
+  VOID(pthread_mutex_lock(&LOCK_assign));
+
+  old_key_cache= key_cache_asmt->key_cache;
+
+  /* Check validity of the index references */ 
+  if (!triggered && table_list->use_index)
+  {
+    key_map kmap= get_key_map_from_key_list(table, table_list->use_index);
+    if (kmap == ~(key_map) 0)
+    {
+      errmsg= thd->net.last_error;
+      error= HA_ADMIN_FAILED;
+      goto err;
+    }
+    if (kmap)
+      map= kmap;
+  }
+
+  len= strlen(new_key_cache_name);
+  new_key_cache= get_or_create_key_cache(new_key_cache_name, len);
+  if (old_key_cache == new_key_cache)
+  {
+    /* Nothing to do: table is assigned to the same key cache */
+    goto ok;
+  }
+                                                         
+  if (!new_key_cache ||
+      (!new_key_cache->cache && ha_key_cache(new_key_cache)))  
+  {
+    if (key_cache_asmt->triggered)
+      error= HA_ERR_OUT_OF_MEM;
+    else         
+    { 
+      char buf[ERRMSGSIZE];
+      my_snprintf(buf, ERRMSGSIZE,
+                  "Failed to create key cache %s", new_key_cache_name);
+      errmsg= buf;
+      error= HA_ADMIN_FAILED;
+    }
+    goto err;
+  }
+
+  reassign_key_cache(key_cache_asmt, new_key_cache);
+       
+  VOID(pthread_mutex_unlock(&LOCK_assign));
+  error= mi_assign_to_keycache(file, map, new_key_cache, &LOCK_assign);
+  VOID(pthread_mutex_lock(&LOCK_assign));
+
+  if (error && !key_cache_asmt->triggered)
+  { 
+    switch (error) {
+    default: 
+      char buf[ERRMSGSIZE+20];
+      my_snprintf(buf, ERRMSGSIZE, 
+                  "Failed to flush to index file (errno: %d)", my_errno);
+      errmsg= buf;
+    }
+    error= HA_ADMIN_CORRUPT;
+    goto err;
+  }
+
+  goto ok;
+
+ err:
+  if (!triggered)
+  {
+    MI_CHECK param;
+    myisamchk_init(&param);
+    param.thd= thd;
+    param.op_name= (char*)"assign_to_keycache";
+    param.db_name= table->table_cache_key;
+    param.table_name= table->table_name;
+    param.testflag= 0;
+    mi_check_print_error(&param, errmsg);
+ }
+
+ ok:
+  if (--key_cache_asmt->requests)
+  {
+    /* There is a queue of assignments for the table */
+
+    /* Remove the first member from the queue */
+    struct st_my_thread_var *last= key_cache_asmt->queue;
+    struct st_my_thread_var *thread= last->next;
+    if (thread->next == thread)
+      key_cache_asmt->queue= 0;
+    else
+    {
+      last->next= thread->next;
+      last->next->prev= &last->next;
+      thread->next= 0;
+    }
+    /* Signal the first waiting thread to proceed */
+    VOID(pthread_cond_signal(&thread->suspend));
+  }
+
+  key_cache_asmt->triggered= 0;
+
+  VOID(pthread_mutex_unlock(&LOCK_assign));
+
+  DBUG_RETURN(error);
+}
+
+
 /*
   Preload pages of the index file for a table into the key cache.
 */

sql/ha_myisam.h

@@ -128,6 +128,7 @@ class ha_myisam: public handler
   int optimize(THD* thd, HA_CHECK_OPT* check_opt);
   int restore(THD* thd, HA_CHECK_OPT* check_opt);
   int backup(THD* thd, HA_CHECK_OPT* check_opt);
+  int assign_to_keycache(THD* thd, HA_CHECK_OPT* check_opt);
   int preload_keys(THD* thd, HA_CHECK_OPT* check_opt);
 #ifdef HAVE_REPLICATION
   int dump(THD* thd, int fd);

sql/ha_myisammrg.cc

@@ -45,6 +45,12 @@ int ha_myisammrg::open(const char *name, int mode, uint test_if_locked)
     DBUG_PRINT("info", ("ha_myisammrg::open exit %d", my_errno));
     return (my_errno ? my_errno : -1);
   }
+  /* Synchronize key cache assignment for the file */
+  KEY_CACHE_VAR *key_cache= table->key_cache ? table->key_cache :
+                                               &dflt_key_cache_var;
+  VOID(myrg_extra(file, HA_EXTRA_SET_KEY_CACHE,
+                  (void*) &key_cache->cache));
+
   DBUG_PRINT("info", ("ha_myisammrg::open myrg_extrafunc..."))
   myrg_extrafunc(file, query_cache_invalidate_by_MyISAM_filename_ref);
   if (!(test_if_locked == HA_OPEN_WAIT_IF_LOCKED ||

sql/item_cmpfunc.h

@@ -235,7 +235,7 @@ public:
   longlong val_int();
   enum Functype functype() const { return NE_FUNC; }
   cond_result eq_cmp_result() const { return COND_FALSE; }
-  optimize_type select_optimize() const { return OPTIMIZE_NONE; }
+  optimize_type select_optimize() const { return OPTIMIZE_KEY; } 
   const char *func_name() const { return "<>"; }
 };
 

sql/sql_base.cc

@@ -30,6 +30,7 @@
 
 TABLE *unused_tables;				/* Used by mysql_test */
 HASH open_cache;				/* Used by mysql_test */
+HASH assign_cache;
 
 static int open_unireg_entry(THD *thd,TABLE *entry,const char *db,
 			     const char *name, const char *alias);
@@ -53,7 +54,6 @@ void table_cache_init(void)
   mysql_rm_tmp_tables();
 }
 
-
 void table_cache_free(void)
 {
   DBUG_ENTER("table_cache_free");
@@ -63,7 +63,6 @@ void table_cache_free(void)
   DBUG_VOID_RETURN;
 }
 
-
 uint cached_tables(void)
 {
   return open_cache.records;
@@ -764,6 +763,8 @@ TABLE *open_table(THD *thd,const char *db,const char *table_name,
   reg1	TABLE *table;
   char	key[MAX_DBKEY_LENGTH];
   uint	key_length;
+  KEY_CACHE_ASMT *key_cache_asmt;
+  KEY_CACHE_VAR *key_cache;
   DBUG_ENTER("open_table");
 
   /* find a unused table in the open table cache */
@@ -804,6 +805,77 @@ TABLE *open_table(THD *thd,const char *db,const char *table_name,
     my_printf_error(ER_TABLE_NOT_LOCKED,ER(ER_TABLE_NOT_LOCKED),MYF(0),alias);
     DBUG_RETURN(0);
   }
+
+  VOID(pthread_mutex_lock(&LOCK_assign));
+  key_cache_asmt= (KEY_CACHE_ASMT*) hash_search(&assign_cache,
+                                              (byte*) key, key_length) ;
+  if (thd->open_options & HA_OPEN_TO_ASSIGN)
+  { 
+    /* When executing a CACHE INDEX command*/   
+    if (key_cache_asmt)
+    {
+      if (key_cache_asmt->requests++)
+      { 
+        /* Another thread are assigning this table to some key cache*/
+
+        /* Put the assignment request into the queue of such requests */
+        struct st_my_thread_var *last;
+        struct st_my_thread_var *thread= thd->mysys_var;        
+        if (! (last= key_cache_asmt->queue))
+          thread->next= thread;
+        else
+        {
+          thread->next= last->next;
+          last->next= thread;
+        }
+        key_cache_asmt->queue= thread;
+        
+        /* Wait until the request can be processed */
+        do
+        {
+          VOID(pthread_cond_wait(&thread->suspend, &LOCK_assign));
+        }
+        while (thread->next);
+      }
+    }
+    else
+    {
+      /* 
+         The table has not been explicitly assigned to any key cache yet;
+         by default it's assigned to the default key cache;
+      */
+      
+      if (!(key_cache_asmt=
+              (KEY_CACHE_ASMT *) my_malloc(sizeof(*key_cache_asmt),
+					   MYF(MY_WME | MY_ZEROFILL)))      ||
+          !(key_cache_asmt->db_name= my_strdup(db, MYF(MY_WME)))            ||
+	  !(key_cache_asmt->table_name= my_strdup(table_name, MYF(MY_WME))) ||
+          !(key_cache_asmt->table_key= my_memdup((const byte *) key,
+						 key_length, MYF(MY_WME))))
+      {
+        VOID(pthread_mutex_unlock(&LOCK_assign));
+        
+        if (key_cache_asmt)
+        {
+          if (key_cache_asmt->db_name)
+            my_free((gptr) key_cache_asmt->db_name, MYF(0));
+          if (key_cache_asmt->table_name)
+            my_free((gptr) key_cache_asmt->table_name, MYF(0));
+          my_free((gptr) key_cache_asmt, MYF(0));
+        }
+        DBUG_RETURN(NULL);
+      }
+      key_cache_asmt->key_length= key_length;
+      key_cache_asmt->key_cache= &dflt_key_cache_var;  
+      VOID(hash_insert(&assign_cache, (byte *) key_cache_asmt));
+      key_cache_asmt->requests++;     
+    }
+    key_cache_asmt->to_reassign= 0;
+  }
+
+  key_cache= key_cache_asmt ? key_cache_asmt->key_cache : &dflt_key_cache_var;  
+  VOID(pthread_mutex_unlock(&LOCK_assign));
+
   VOID(pthread_mutex_lock(&LOCK_open));
 
   if (!thd->open_tables)
@@ -846,6 +918,9 @@ TABLE *open_table(THD *thd,const char *db,const char *table_name,
     }
     table->prev->next=table->next;		/* Remove from unused list */
     table->next->prev=table->prev;
+
+    table->key_cache= key_cache;
+    table->key_cache_asmt= key_cache_asmt;
   }
   else
   {
@@ -859,6 +934,8 @@ TABLE *open_table(THD *thd,const char *db,const char *table_name,
       VOID(pthread_mutex_unlock(&LOCK_open));
       DBUG_RETURN(NULL);
     }
+    table->key_cache= key_cache;
+    table->key_cache_asmt= key_cache_asmt;
     if (open_unireg_entry(thd, table,db,table_name,alias) ||
 	!(table->table_cache_key=memdup_root(&table->mem_root,(char*) key,
 					     key_length)))
@@ -877,6 +954,8 @@ TABLE *open_table(THD *thd,const char *db,const char *table_name,
 
   table->in_use=thd;
   check_unused();
+
+       
   VOID(pthread_mutex_unlock(&LOCK_open));
   if (refresh)
   {
@@ -1648,6 +1727,54 @@ bool rm_temporary_table(enum db_type base, char *path)
   DBUG_RETURN(error);
 }
 
+static void free_assign_entry(KEY_CACHE_ASMT *key_cache_asmt)
+{
+  DBUG_ENTER("free_assign_entry");
+  my_free((gptr) key_cache_asmt->table_key, MYF(0));
+  my_free((gptr) key_cache_asmt, MYF(0));
+  DBUG_VOID_RETURN;
+}
+
+static byte *assign_cache_key(const byte *record,uint *length,
+				 my_bool not_used __attribute__((unused)))
+{
+  KEY_CACHE_ASMT *entry=(KEY_CACHE_ASMT *) record;
+  *length=entry->key_length;
+  return (byte*) entry->table_key;
+}
+
+void assign_cache_init(void)
+{
+  VOID(hash_init(&assign_cache, &my_charset_bin,
+		 table_cache_size+16, 0, 0, assign_cache_key,
+		 (hash_free_key) free_assign_entry,0));
+}
+
+void assign_cache_free(void)
+{
+  DBUG_ENTER("assign_cache_free");
+  hash_free(&assign_cache);
+  DBUG_VOID_RETURN;
+}
+
+void reassign_key_cache(KEY_CACHE_ASMT *key_cache_asmt,
+                        KEY_CACHE_VAR *new_key_cache)
+{
+  if (key_cache_asmt->prev)
+  { 
+    /* Unlink key_cache_asmt from the assignment list for the old key cache */
+    if ((*key_cache_asmt->prev= key_cache_asmt->next))
+      key_cache_asmt->next->prev= key_cache_asmt->prev;
+  }
+  /* Link key_cache_asmt into the assignment list for the new key cache */
+  key_cache_asmt->prev= &new_key_cache->assign_list;
+  if ((key_cache_asmt->next= new_key_cache->assign_list))
+    key_cache_asmt->next->prev= &key_cache_asmt->next;
+  new_key_cache->assign_list= key_cache_asmt;
+
+  key_cache_asmt->key_cache= new_key_cache;
+}
+
 
 /*****************************************************************************
 ** find field in list or tables. if field is unqualifed and unique,

sql/sql_test.cc

@@ -319,8 +319,9 @@ w_requests: %10lu\n\
 writes:     %10lu\n\
 r_requests: %10lu\n\
 reads:      %10lu\n",
-	 my_blocks_used,my_blocks_changed,my_cache_w_requests,
-	 my_cache_write,my_cache_r_requests,my_cache_read);
+	 dflt_key_cache_var.blocks_used,dflt_key_cache_var.blocks_changed,
+         dflt_key_cache_var.cache_w_requests,dflt_key_cache_var.cache_write,
+         dflt_key_cache_var.cache_r_requests,dflt_key_cache_var.cache_read);
   pthread_mutex_unlock(&THR_LOCK_keycache);
 
   if (thd)