mirror of
https://github.com/MariaDB/server.git
synced 2025-01-21 14:32:34 +01:00
5cbf4e3840
Implement a limit on the memory used by the INNODB_TRX, INNODB_LOCKS and INNODB_LOCK_WAITS tables. The maximum allowed memory is defined with the macro TRX_I_S_MEM_LIMIT. Approved by: Marko (via IM)
113 lines
3.9 KiB
C
113 lines
3.9 KiB
C
/******************************************************
|
|
Hash storage.
|
|
Provides a data structure that stores chunks of data in
|
|
its own storage, avoiding duplicates.
|
|
|
|
(c) 2007 Innobase Oy
|
|
|
|
Created September 22, 2007 Vasil Dimov
|
|
*******************************************************/
|
|
|
|
#ifndef ha0storage_h
|
|
#define ha0storage_h
|
|
|
|
#include "univ.i"
|
|
|
|
/* This value is used by default by ha_storage_create(). More memory
|
|
is allocated later when/if it is needed. */
|
|
#define HA_STORAGE_DEFAULT_HEAP_BYTES 1024
|
|
|
|
/* This value is used by default by ha_storage_create(). It is a
|
|
constant per ha_storage's lifetime. */
|
|
#define HA_STORAGE_DEFAULT_HASH_CELLS 4096
|
|
|
|
typedef struct ha_storage_struct ha_storage_t;
|
|
|
|
/***********************************************************************
|
|
Creates a hash storage. If any of the parameters is 0, then a default
|
|
value is used. */
|
|
UNIV_INLINE
|
|
ha_storage_t*
|
|
ha_storage_create(
|
|
/*==============*/
|
|
/* out, own: hash storage */
|
|
ulint initial_heap_bytes, /* in: initial heap's size */
|
|
ulint initial_hash_cells); /* in: initial number of cells
|
|
in the hash table */
|
|
|
|
/***********************************************************************
|
|
Copies data into the storage and returns a pointer to the copy. If the
|
|
same data chunk is already present, then pointer to it is returned.
|
|
Data chunks are considered to be equal if len1 == len2 and
|
|
memcmp(data1, data2, len1) == 0. If "data" is not present (and thus
|
|
data_len bytes need to be allocated) and the size of storage is going to
|
|
become more than "memlim" then "data" is not added and NULL is returned.
|
|
To disable this behavior "memlim" can be set to 0, which stands for
|
|
"no limit". */
|
|
|
|
const void*
|
|
ha_storage_put_memlim(
|
|
/*==================*/
|
|
/* out: pointer to the copy */
|
|
ha_storage_t* storage, /* in/out: hash storage */
|
|
const void* data, /* in: data to store */
|
|
ulint data_len, /* in: data length */
|
|
ulint memlim); /* in: memory limit to obey */
|
|
|
|
/***********************************************************************
|
|
Same as ha_storage_put_memlim() but without memory limit. */
|
|
|
|
#define ha_storage_put(storage, data, data_len) \
|
|
ha_storage_put_memlim((storage), (data), (data_len), 0)
|
|
|
|
/***********************************************************************
|
|
Copies string into the storage and returns a pointer to the copy. If the
|
|
same string is already present, then pointer to it is returned.
|
|
Strings are considered to be equal if strcmp(str1, str2) == 0. */
|
|
|
|
#define ha_storage_put_str(storage, str) \
|
|
((const char*) ha_storage_put((storage), (str), strlen(str) + 1))
|
|
|
|
/***********************************************************************
|
|
Copies string into the storage and returns a pointer to the copy obeying
|
|
a memory limit. */
|
|
|
|
#define ha_storage_put_str_memlim(storage, str, memlim) \
|
|
((const char*) ha_storage_put_memlim((storage), (str), \
|
|
strlen(str) + 1, (memlim)))
|
|
|
|
/***********************************************************************
|
|
Empties a hash storage, freeing memory occupied by data chunks.
|
|
This invalidates any pointers previously returned by ha_storage_put().
|
|
The hash storage is not invalidated itself and can be used again. */
|
|
UNIV_INLINE
|
|
void
|
|
ha_storage_empty(
|
|
/*=============*/
|
|
ha_storage_t** storage); /* in/out: hash storage */
|
|
|
|
/***********************************************************************
|
|
Frees a hash storage and everything it contains, it cannot be used after
|
|
this call.
|
|
This invalidates any pointers previously returned by ha_storage_put().
|
|
*/
|
|
UNIV_INLINE
|
|
void
|
|
ha_storage_free(
|
|
/*============*/
|
|
ha_storage_t* storage); /* in/out: hash storage */
|
|
|
|
/***********************************************************************
|
|
Gets the size of the memory used by a storage. */
|
|
UNIV_INLINE
|
|
ulint
|
|
ha_storage_get_size(
|
|
/*================*/
|
|
/* out: bytes used */
|
|
const ha_storage_t* storage); /* in: hash storage */
|
|
|
|
#ifndef UNIV_NONINL
|
|
#include "ha0storage.ic"
|
|
#endif
|
|
|
|
#endif /* ha0storage_h */
|