MySQL 8.4.3
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trx0i_s.h
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27
28/** @file include/trx0i_s.h
29 INFORMATION SCHEMA innodb_trx, innodb_locks and
30 innodb_lock_waits tables cache structures and public
31 functions.
32
33 Created July 17, 2007 Vasil Dimov
34 *******************************************************/
35
36#ifndef trx0i_s_h
37#define trx0i_s_h
38
39#include <optional>
40
41#include "dict0types.h"
42#include "lock0types.h"
43#include "trx0types.h"
44#include "univ.i"
45
47
48struct CHARSET_INFO;
49
50/** The maximum amount of memory that can be consumed by innodb_trx,
51innodb_locks and innodb_lock_waits information schema tables. */
52constexpr uint32_t TRX_I_S_MEM_LIMIT = 16777216; /* 16 MiB */
53
54/** The maximum length of a string that can be stored in
55i_s_locks_row_t::lock_data */
56constexpr uint32_t TRX_I_S_LOCK_DATA_MAX_LEN = 8192;
57
58/** The maximum length of a string that can be stored in
59i_s_trx_row_t::trx_query */
60constexpr uint32_t TRX_I_S_TRX_QUERY_MAX_LEN = 1024;
61
62/** The maximum length of a string that can be stored in
63i_s_trx_row_t::trx_operation_state */
64constexpr uint32_t TRX_I_S_TRX_OP_STATE_MAX_LEN = 64;
65
66/** The maximum length of a string that can be stored in
67i_s_trx_row_t::trx_foreign_key_error */
68constexpr uint32_t TRX_I_S_TRX_FK_ERROR_MAX_LEN = 256;
69
70/** The maximum length of a string that can be stored in
71i_s_trx_row_t::trx_isolation_level */
73
74/** Safely copy strings in to the INNODB_TRX table's
75string based columns */
76#define TRX_I_S_STRING_COPY(data, field, constraint, tcache) \
77 do { \
78 if (strlen(data) > constraint) { \
79 char buff[constraint + 1]; \
80 strncpy(buff, data, constraint); \
81 buff[constraint] = '\0'; \
82 \
83 field = static_cast<const char *>( \
84 ha_storage_put_memlim((tcache)->storage, buff, constraint + 1, \
85 MAX_ALLOWED_FOR_STORAGE(tcache))); \
86 } else { \
87 field = static_cast<const char *>(ha_storage_put_str_memlim( \
88 (tcache)->storage, data, MAX_ALLOWED_FOR_STORAGE(tcache))); \
89 } \
90 } while (0)
91
92/** This structure represents INFORMATION_SCHEMA.innodb_locks row */
94 /** The unique identifier of this lock, which does not change over time for a
95 single lock request and no two lock requests ever have the same guid. */
97
98 /** Information for record locks. All these are
99 ULINT_UNDEFINED for table locks. */
100 /** @{ */
101 space_id_t lock_space; /*!< tablespace identifier */
102 page_no_t lock_page; /*!< page number within the_space */
103 ulint lock_rec; /*!< heap number of the record
104 on the page */
105 /** @} */
106
107 /** The following are auxiliary and not included in the table */
108 /** @{ */
110 /*!< table identifier from
111 lock_get_table_id */
112 /** @} */
113};
114
115/** This structure represents INFORMATION_SCHEMA.innodb_trx row */
117 /** transaction identifier */
119
120 /** transaction state from trx_get_que_state_str()*/
121 const char *trx_state;
122
123 /** trx_t::start_time */
124 std::chrono::system_clock::time_point trx_started;
125
126 /** a description of lock request if trx is waiting, or nullptr otherwise */
128
129 /** The value of trx->lock.wait_started */
130 std::chrono::system_clock::time_point trx_wait_started;
131
132 /** The value of TRX_WEIGHT(trx) */
133 uintmax_t trx_weight;
134
135 /** If `first` is `true` then `second` is the value of the
136 trx->lock.schedule_weight, otherwise the `second` should be ignored and
137 displayed as NULL to the end user.
138 (This could be std::optional once we move to C++17) */
139 std::pair<bool, trx_schedule_weight_t> trx_schedule_weight;
140
141 /** thd_get_thread_id() */
143
144 /** TRX_I_S_TRX_QUERY_MAX_LEN byte prefix of MySQL statement being executed
145 in the transaction */
146 const char *trx_query;
147
148 /** the charset of trx_query */
150
151 /** trx_t::op_info */
153
154 /** n_mysql_tables_in_use in trx_t*/
156
157 /** mysql_n_tables_locked in trx_t */
159
160 /** list len of trx_locks in trx_t */
162
163 /** mem_heap_get_size(trx->lock_heap) */
165
166 /** lock_number_of_rows_locked() */
168
169 /** trx_t::undo_no */
171
172 /** n_tickets_to_enter_innodb in trx_t */
174
175 /** isolation_level in trx_t */
177
178 /** check_unique_secondary in trx_t */
180
181 /** check_foreigns in trx_t */
183
184 /** detailed_error in trx_t */
186
187 /** has_search_latch in trx_t */
189
190 /** trx_t::read_only */
192
193 /** trx_is_autocommit_non_locking(trx) */
195};
196
197/** Cache of INFORMATION_SCHEMA table data */
198struct trx_i_s_cache_t;
199
200/** Auxiliary enum used by functions that need to select one of the
201INFORMATION_SCHEMA tables */
203 I_S_INNODB_TRX, /*!< INFORMATION_SCHEMA.innodb_trx */
204};
205
206/** This is the intermediate buffer where data needed to fill the
207INFORMATION SCHEMA tables is fetched and later retrieved by the C++
208code in handler/i_s.cc. */
210
211/** Initialize INFORMATION SCHEMA trx related cache. */
212void trx_i_s_cache_init(trx_i_s_cache_t *cache); /*!< out: cache to init */
213/** Free the INFORMATION SCHEMA trx related cache. */
214void trx_i_s_cache_free(trx_i_s_cache_t *cache); /*!< in/out: cache to free */
215
216/** Issue a shared/read lock on the tables cache. */
217void trx_i_s_cache_start_read(trx_i_s_cache_t *cache); /*!< in: cache */
218
219/** Release a shared/read lock on the tables cache. */
220void trx_i_s_cache_end_read(trx_i_s_cache_t *cache); /*!< in: cache */
221
222/** Issue an exclusive/write lock on the tables cache. */
223void trx_i_s_cache_start_write(trx_i_s_cache_t *cache); /*!< in: cache */
224
225/** Release an exclusive/write lock on the tables cache. */
226void trx_i_s_cache_end_write(trx_i_s_cache_t *cache); /*!< in: cache */
227
228/** Retrieves the number of used rows in the cache for a given
229 INFORMATION SCHEMA table.
230 @return number of rows */
231ulint trx_i_s_cache_get_rows_used(trx_i_s_cache_t *cache, /*!< in: cache */
232 enum i_s_table table); /*!< in: which table */
233
234/** Retrieves the nth row in the cache for a given INFORMATION SCHEMA
235 table.
236 @return row */
237void *trx_i_s_cache_get_nth_row(trx_i_s_cache_t *cache, /*!< in: cache */
238 enum i_s_table table, /*!< in: which table */
239 ulint n); /*!< in: row number */
240
241/** Update the transactions cache if it has not been read for some time.
242 @return 0 - fetched, 1 - not */
244 trx_i_s_cache_t *cache); /*!< in/out: cache */
245
246/** Returns true if the data in the cache is truncated due to the memory
247 limit posed by TRX_I_S_MEM_LIMIT.
248 @param[in] cache The cache
249 @return true if truncated */
251
252/** The maximum length of a resulting lock_id_size in
253trx_i_s_create_lock_id(), not including the terminating NUL.
254"%lu:%lu:%lu:%lu:%lu:%lu" -> 20*6+5 chars */
255constexpr uint32_t TRX_I_S_LOCK_ID_MAX_LEN = 20 * 6 + 5;
256
257/** Crafts a lock id string from a i_s_locks_row_t object. Returns its
258 second argument. This function aborts if there is not enough space in
259 lock_id. Be sure to provide at least TRX_I_S_LOCK_ID_MAX_LEN + 1 if you
260 want to be 100% sure that it will not abort.
261 @param[in] row
262 The description of the lock sufficient to populate a row
263 @param[out] lock_id
264 The buffer to store the resulting lock_id
265 @param[in] lock_id_size
266 The size of the lock_id buffer
267 @return resulting lock id */
268char *trx_i_s_create_lock_id(const i_s_locks_row_t &row, char *lock_id,
269 size_t lock_id_size);
270
271/** Fill performance schema lock data.
272Create a string that represents the LOCK_DATA
273column, for a given lock record.
274@param[out] lock_data Lock data string
275@param[in] lock Lock to inspect
276@param[in] heap_no Lock heap number
277@param[in] container Data container to fill
278*/
279void p_s_fill_lock_data(const char **lock_data, const lock_t *lock,
280 ulint heap_no,
282
283/** Fills i_s_locks_row_t object with data about the lock.
284@param[out] row Result object that's filled
285@param[in] lock Lock to get data from
286@param[in] heap_no Lock's record number or ULINT_UNDEFINED if the lock is a
287 table lock */
288void fill_locks_row(i_s_locks_row_t *row, const lock_t *lock, ulint heap_no);
289
290/** Parses lock id into row
291@param[in] lock_id Lock id generated with trx_i_s_create_lock_id
292@param[out] row Row to be filled in with data
293@return LOCK_REC, LOCK_TABLE or 0 if failed to parse */
294int trx_i_s_parse_lock_id(const char *lock_id, i_s_locks_row_t *row);
295#endif /* trx0i_s_h */
uint32_t space_id_t
Tablespace identifier.
Definition: api0api.h:48
uint32_t page_no_t
Page number.
Definition: api0api.h:46
Server interface, row lock container.
Definition: psi_data_lock.h:117
Data dictionary global types.
ib_id_t table_id_t
Table or partition identifier (unique within an InnoDB instance).
Definition: dict0types.h:232
The transaction lock system global types.
static PFS_engine_table_share_proxy table
Definition: pfs.cc:61
Definition: atomics_array.h:39
Provides atomic access in shared-exclusive modes.
Definition: shared_spin_lock.h:79
Definition: m_ctype.h:423
This structure represents INFORMATION_SCHEMA.innodb_locks row.
Definition: trx0i_s.h:93
space_id_t lock_space
Information for record locks.
Definition: trx0i_s.h:101
ulint lock_rec
heap number of the record on the page
Definition: trx0i_s.h:103
lock_guid_t lock_guid
The unique identifier of this lock, which does not change over time for a single lock request and no ...
Definition: trx0i_s.h:96
table_id_t lock_table_id
The following are auxiliary and not included in the table.
Definition: trx0i_s.h:109
page_no_t lock_page
page number within the_space
Definition: trx0i_s.h:102
This structure represents INFORMATION_SCHEMA.innodb_trx row.
Definition: trx0i_s.h:116
ulint trx_lock_memory_bytes
mem_heap_get_size(trx->lock_heap)
Definition: trx0i_s.h:164
ulint trx_rows_locked
lock_number_of_rows_locked()
Definition: trx0i_s.h:167
std::chrono::system_clock::time_point trx_started
trx_t::start_time
Definition: trx0i_s.h:124
const char * trx_isolation_level
isolation_level in trx_t
Definition: trx0i_s.h:176
bool trx_unique_checks
check_unique_secondary in trx_t
Definition: trx0i_s.h:179
std::pair< bool, trx_schedule_weight_t > trx_schedule_weight
If first is true then second is the value of the trx->lock.schedule_weight, otherwise the second shou...
Definition: trx0i_s.h:139
ulint trx_tables_locked
mysql_n_tables_locked in trx_t
Definition: trx0i_s.h:158
const char * trx_state
transaction state from trx_get_que_state_str()
Definition: trx0i_s.h:121
ulint trx_concurrency_tickets
n_tickets_to_enter_innodb in trx_t
Definition: trx0i_s.h:173
bool trx_has_search_latch
has_search_latch in trx_t
Definition: trx0i_s.h:188
const char * trx_foreign_key_error
detailed_error in trx_t
Definition: trx0i_s.h:185
const CHARSET_INFO * trx_query_cs
the charset of trx_query
Definition: trx0i_s.h:149
trx_id_t trx_id
transaction identifier
Definition: trx0i_s.h:118
const char * trx_operation_state
trx_t::op_info
Definition: trx0i_s.h:152
ulint trx_mysql_thread_id
thd_get_thread_id()
Definition: trx0i_s.h:142
ulint trx_is_read_only
trx_t::read_only
Definition: trx0i_s.h:191
ulint trx_lock_structs
list len of trx_locks in trx_t
Definition: trx0i_s.h:161
ulint trx_tables_in_use
n_mysql_tables_in_use in trx_t
Definition: trx0i_s.h:155
bool trx_foreign_key_checks
check_foreigns in trx_t
Definition: trx0i_s.h:182
ulint trx_is_autocommit_non_locking
trx_is_autocommit_non_locking(trx)
Definition: trx0i_s.h:194
const char * trx_query
TRX_I_S_TRX_QUERY_MAX_LEN byte prefix of MySQL statement being executed in the transaction.
Definition: trx0i_s.h:146
std::chrono::system_clock::time_point trx_wait_started
The value of trx->lock.wait_started.
Definition: trx0i_s.h:130
const i_s_locks_row_t * requested_lock_row
a description of lock request if trx is waiting, or nullptr otherwise
Definition: trx0i_s.h:127
uintmax_t trx_weight
The value of TRX_WEIGHT(trx)
Definition: trx0i_s.h:133
uintmax_t trx_rows_modified
trx_t::undo_no
Definition: trx0i_s.h:170
Used to represent locks requests uniquely over time.
Definition: lock0types.h:106
Lock struct; protected by lock_sys latches.
Definition: lock0priv.h:137
This structure describes the intermediate buffer.
Definition: trx0i_s.cc:131
void trx_i_s_cache_end_read(trx_i_s_cache_t *cache)
Release a shared/read lock on the tables cache.
Definition: trx0i_s.cc:893
void trx_i_s_cache_start_read(trx_i_s_cache_t *cache)
Issue a shared/read lock on the tables cache.
Definition: trx0i_s.cc:887
constexpr uint32_t TRX_I_S_MEM_LIMIT
The maximum amount of memory that can be consumed by innodb_trx, innodb_locks and innodb_lock_waits i...
Definition: trx0i_s.h:52
void * trx_i_s_cache_get_nth_row(trx_i_s_cache_t *cache, enum i_s_table table, ulint n)
Retrieves the nth row in the cache for a given INFORMATION SCHEMA table.
Definition: trx0i_s.cc:955
void trx_i_s_cache_start_write(trx_i_s_cache_t *cache)
Issue an exclusive/write lock on the tables cache.
Definition: trx0i_s.cc:904
void fill_locks_row(i_s_locks_row_t *row, const lock_t *lock, ulint heap_no)
Fills i_s_locks_row_t object with data about the lock.
Definition: trx0i_s.cc:652
bool trx_i_s_cache_is_truncated(trx_i_s_cache_t *cache)
Returns true if the data in the cache is truncated due to the memory limit posed by TRX_I_S_MEM_LIMIT...
Definition: trx0i_s.cc:838
constexpr uint32_t TRX_I_S_TRX_FK_ERROR_MAX_LEN
The maximum length of a string that can be stored in i_s_trx_row_t::trx_foreign_key_error.
Definition: trx0i_s.h:68
trx_i_s_cache_t * trx_i_s_cache
This is the intermediate buffer where data needed to fill the INFORMATION SCHEMA tables is fetched an...
Definition: trx0i_s.cc:167
constexpr uint32_t TRX_I_S_TRX_ISOLATION_LEVEL_MAX_LEN
The maximum length of a string that can be stored in i_s_trx_row_t::trx_isolation_level.
Definition: trx0i_s.h:72
ulint trx_i_s_cache_get_rows_used(trx_i_s_cache_t *cache, enum i_s_table table)
Retrieves the number of used rows in the cache for a given INFORMATION SCHEMA table.
Definition: trx0i_s.cc:942
int trx_i_s_possibly_fetch_data_into_cache(trx_i_s_cache_t *cache)
Update the transactions cache if it has not been read for some time.
Definition: trx0i_s.cc:817
constexpr uint32_t TRX_I_S_TRX_OP_STATE_MAX_LEN
The maximum length of a string that can be stored in i_s_trx_row_t::trx_operation_state.
Definition: trx0i_s.h:64
constexpr uint32_t TRX_I_S_TRX_QUERY_MAX_LEN
The maximum length of a string that can be stored in i_s_trx_row_t::trx_query.
Definition: trx0i_s.h:60
void trx_i_s_cache_end_write(trx_i_s_cache_t *cache)
Release an exclusive/write lock on the tables cache.
Definition: trx0i_s.cc:910
constexpr uint32_t TRX_I_S_LOCK_ID_MAX_LEN
The maximum length of a resulting lock_id_size in trx_i_s_create_lock_id(), not including the termina...
Definition: trx0i_s.h:255
void trx_i_s_cache_free(trx_i_s_cache_t *cache)
Free the INFORMATION SCHEMA trx related cache.
Definition: trx0i_s.cc:875
int trx_i_s_parse_lock_id(const char *lock_id, i_s_locks_row_t *row)
Parses lock id into row.
Definition: trx0i_s.cc:1023
i_s_table
Auxiliary enum used by functions that need to select one of the INFORMATION_SCHEMA tables.
Definition: trx0i_s.h:202
@ I_S_INNODB_TRX
INFORMATION_SCHEMA.innodb_trx.
Definition: trx0i_s.h:203
char * trx_i_s_create_lock_id(const i_s_locks_row_t &row, char *lock_id, size_t lock_id_size)
Crafts a lock id string from a i_s_locks_row_t object.
Definition: trx0i_s.cc:989
constexpr uint32_t TRX_I_S_LOCK_DATA_MAX_LEN
The maximum length of a string that can be stored in i_s_locks_row_t::lock_data.
Definition: trx0i_s.h:56
void p_s_fill_lock_data(const char **lock_data, const lock_t *lock, ulint heap_no, PSI_server_data_lock_container *container)
Fill performance schema lock data.
Definition: trx0i_s.cc:587
void trx_i_s_cache_init(trx_i_s_cache_t *cache)
Initialize INFORMATION SCHEMA trx related cache.
Definition: trx0i_s.cc:843
Transaction system global type definitions.
ib_id_t trx_id_t
Transaction identifier (DB_TRX_ID, DATA_TRX_ID)
Definition: trx0types.h:138
Version control for database, common definitions, and include files.
unsigned long int ulint
Definition: univ.i:406
int n
Definition: xcom_base.cc:509