MySQL 9.1.0
Source Code Documentation
srv0conc.h
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40
41/** @file include/srv0conc.h
42
43 InnoDB concurrency manager header file
44
45 Created 2011/04/18 Sunny Bains
46 *******************************************************/
47
48#ifndef srv_conc_h
49#define srv_conc_h
50
51/** We are prepared for a situation that we have this many threads waiting for
52a semaphore inside InnoDB. */
53
54extern uint32_t srv_max_n_threads;
55
56/** The following controls how many threads we let inside InnoDB concurrently:
57threads waiting for locks are not counted into the number because otherwise
58we could get a deadlock. Value of 0 will disable the concurrency check. */
59
60extern ulong srv_thread_concurrency;
61
62struct row_prebuilt_t;
63/** Puts an OS thread to wait if there are too many concurrent threads
64 (>= srv_thread_concurrency) inside InnoDB. The threads wait in a FIFO queue.
65 @param[in,out] prebuilt row prebuilt handler
66 @return Innodb error code. */
68
69/** This lets a thread enter InnoDB regardless of the number of threads inside
70 InnoDB. This must be called when a thread ends a lock wait. */
71void srv_conc_force_enter_innodb(trx_t *trx); /*!< in: transaction object
72 associated with the thread */
73
74/** This must be called when a thread exits InnoDB in a lock wait or at the
75 end of an SQL statement. */
76void srv_conc_force_exit_innodb(trx_t *trx); /*!< in: transaction object
77 associated with the thread */
78
79/** Get the count of threads waiting inside InnoDB. */
81
82/** Get the count of threads active inside InnoDB. */
83int32_t srv_conc_get_active_threads(void);
84
85#endif /* srv_conc_h */
dberr_t
Definition: db0err.h:39
int32_t srv_conc_get_active_threads(void)
Get the count of threads active inside InnoDB.
Definition: srv0conc.cc:285
void srv_conc_force_exit_innodb(trx_t *trx)
This must be called when a thread exits InnoDB in a lock wait or at the end of an SQL statement.
Definition: srv0conc.cc:259
ulong srv_thread_concurrency
The following controls how many threads we let inside InnoDB concurrently: threads waiting for locks ...
Definition: srv0conc.cc:71
int32_t srv_conc_get_waiting_threads(void)
Get the count of threads waiting inside InnoDB.
Definition: srv0conc.cc:280
dberr_t srv_conc_enter_innodb(row_prebuilt_t *prebuilt)
Puts an OS thread to wait if there are too many concurrent threads (>= srv_thread_concurrency) inside...
Definition: srv0conc.cc:218
uint32_t srv_max_n_threads
We are prepared for a situation that we have this many threads waiting for a semaphore inside InnoDB.
Definition: os0thread.cc:53
void srv_conc_force_enter_innodb(trx_t *trx)
This lets a thread enter InnoDB regardless of the number of threads inside InnoDB.
Definition: srv0conc.cc:234
A struct for (sometimes lazily) prebuilt structures in an Innobase table handle used within MySQL; th...
Definition: row0mysql.h:515
trx_t * trx
current transaction handle
Definition: row0mysql.h:525
Definition: trx0trx.h:675