/* Copyright (C) 2006 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 */ /* Preload indexes into key cache */ #include "maria_def.h" /* Preload pages of the index file for a table into the key cache SYNOPSIS maria_preload() info open table map map of indexes to preload into key cache ignore_leaves only non-leaves pages are to be preloaded RETURN VALUE 0 if a success. error code - otherwise. NOTES. At present pages for all indexes are preloaded. In future only pages for indexes specified in the key_map parameter of the table will be preloaded. */ int maria_preload(MARIA_HA *info, ulonglong key_map, my_bool ignore_leaves) { uint i; ulong length, block_length= 0; uchar *buff= NULL; MARIA_SHARE* share= info->s; uint keys= share->state.header.keys; MARIA_KEYDEF *keyinfo= share->keyinfo; my_off_t key_file_length= share->state.state.key_file_length; my_off_t pos= share->base.keystart; DBUG_ENTER("maria_preload"); if (!keys || !maria_is_any_key_active(key_map) || key_file_length == pos) DBUG_RETURN(0); block_length= keyinfo[0].block_length; /* Check whether all indexes use the same block size */ for (i= 1 ; i < keys ; i++) { if (keyinfo[i].block_length != block_length) DBUG_RETURN(my_errno= HA_ERR_NON_UNIQUE_BLOCK_SIZE); } length= info->preload_buff_size/block_length * block_length; set_if_bigger(length, block_length); if (!(buff= (uchar *) my_malloc(length, MYF(MY_WME)))) DBUG_RETURN(my_errno= HA_ERR_OUT_OF_MEM); if (flush_key_blocks(share->key_cache,share->kfile, FLUSH_RELEASE)) goto err; do { /* Read the next block of index file into the preload buffer */ if ((my_off_t) length > (key_file_length-pos)) length= (ulong) (key_file_length-pos); if (my_pread(share->kfile, (byte*) buff, length, pos, MYF(MY_FAE|MY_FNABP))) goto err; if (ignore_leaves) { uchar *end= buff+length; do { if (_ma_test_if_nod(buff)) { if (key_cache_insert(share->key_cache, share->kfile, pos, DFLT_INIT_HITS, (byte*) buff, block_length)) goto err; } pos+= block_length; } while ((buff+= block_length) != end); buff= end-length; } else { if (key_cache_insert(share->key_cache, share->kfile, pos, DFLT_INIT_HITS, (byte*) buff, length)) goto err; pos+= length; } } while (pos != key_file_length); my_free((char*) buff, MYF(0)); DBUG_RETURN(0); err: my_free((char*) buff, MYF(MY_ALLOW_ZERO_PTR)); DBUG_RETURN(my_errno= errno); }