1
/* Copyright (C) 2000 MySQL AB
3
This program is free software; you can redistribute it and/or modify
4
it under the terms of the GNU General Public License as published by
5
the Free Software Foundation; version 2 of the License.
7
This program is distributed in the hope that it will be useful,
8
but WITHOUT ANY WARRANTY; without even the implied warranty of
9
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10
GNU General Public License for more details.
12
You should have received a copy of the GNU General Public License
13
along with this program; if not, write to the Free Software
14
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
17
Data structures for mysys/my_alloc.c (root memory allocator)
23
#define ALLOC_MAX_BLOCK_TO_DROP 4096
24
#define ALLOC_MAX_BLOCK_USAGE_BEFORE_DROP 10
26
typedef struct st_used_mem
27
{ /* struct for once_alloc (block) */
28
struct st_used_mem *next; /* Next block in use */
29
unsigned int left; /* memory left in block */
30
unsigned int size; /* size of block */
34
typedef struct st_mem_root
36
USED_MEM *free; /* blocks with free memory in it */
37
USED_MEM *used; /* blocks almost without free memory */
38
USED_MEM *pre_alloc; /* preallocated block */
39
/* if block have less memory it will be put in 'used' list */
41
size_t block_size; /* initial block size */
42
unsigned int block_num; /* allocated blocks counter */
44
first free block in queue test counter (if it exceed
45
MAX_BLOCK_USAGE_BEFORE_DROP block will be dropped in 'used' list)
47
unsigned int first_block_usage;
49
void (*error_handler)(void);