/****************************************************** The database server main program NOTE: SQL Server 7 uses something which the documentation calls user mode scheduled threads (UMS threads). One such thread is usually allocated per processor. Win32 documentation does not know any UMS threads, which suggests that the concept is internal to SQL Server 7. It may mean that SQL Server 7 does all the scheduling of threads itself, even in i/o waits. We should maybe modify InnoDB to use the same technique, because thread switches within NT may be too slow. SQL Server 7 also mentions fibers, which are cooperatively scheduled threads. They can boost performance by 5 %, according to the Delaney and Soukup's book. Windows 2000 will have something called thread pooling (see msdn website), which we could possibly use. Another possibility could be to use some very fast user space thread library. This might confuse NT though. (c) 1995 Innobase Oy Created 10/8/1995 Heikki Tuuri *******************************************************/ /* Dummy comment */ #include "srv0srv.h" #include "ut0mem.h" #include "os0proc.h" #include "mem0mem.h" #include "mem0pool.h" #include "sync0sync.h" #include "sync0ipm.h" #include "thr0loc.h" #include "com0com.h" #include "com0shm.h" #include "que0que.h" #include "srv0que.h" #include "log0recv.h" #include "odbc0odbc.h" #include "pars0pars.h" #include "usr0sess.h" #include "lock0lock.h" #include "trx0purge.h" #include "ibuf0ibuf.h" #include "buf0flu.h" #include "btr0sea.h" #include "dict0load.h" #include "srv0start.h" #include "row0mysql.h" /* This is set to TRUE if the MySQL user has set it in MySQL; currently affects only FOREIGN KEY definition parsing */ ibool srv_lower_case_table_names = FALSE; /* Buffer which can be used in printing fatal error messages */ char srv_fatal_errbuf[5000]; /* The following counter is incremented whenever there is some user activity in the server */ ulint srv_activity_count = 0; ibool srv_lock_timeout_and_monitor_active = FALSE; ibool srv_error_monitor_active = FALSE; char* srv_main_thread_op_info = (char*) ""; /* Server parameters which are read from the initfile */ /* The following three are dir paths which are catenated before file names, where the file name itself may also contain a path */ char* srv_data_home = NULL; char* srv_arch_dir = NULL; ulint srv_n_data_files = 0; char** srv_data_file_names = NULL; ulint* srv_data_file_sizes = NULL; /* size in database pages */ ibool srv_auto_extend_last_data_file = FALSE; /* if TRUE, then we auto-extend the last data file */ ulint srv_last_file_size_max = 0; /* if != 0, this tells the max size auto-extending may increase the last data file size */ ulint* srv_data_file_is_raw_partition = NULL; /* If the following is TRUE we do not allow inserts etc. This protects the user from forgetting the 'newraw' keyword to my.cnf */ ibool srv_created_new_raw = FALSE; char** srv_log_group_home_dirs = NULL; ulint srv_n_log_groups = ULINT_MAX; ulint srv_n_log_files = ULINT_MAX; ulint srv_log_file_size = ULINT_MAX; /* size in database pages */ ibool srv_log_archive_on = TRUE; ulint srv_log_buffer_size = ULINT_MAX; /* size in database pages */ ulint srv_flush_log_at_trx_commit = 1; byte srv_latin1_ordering[256] /* The sort order table of the latin1 character set. The following table is the MySQL order as of Feb 10th, 2002 */ = { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07 , 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F , 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17 , 0x18, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F , 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27 , 0x28, 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F , 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37 , 0x38, 0x39, 0x3A, 0x3B, 0x3C, 0x3D, 0x3E, 0x3F , 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47 , 0x48, 0x49, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x4F , 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57 , 0x58, 0x59, 0x5A, 0x5B, 0x5C, 0x5D, 0x5E, 0x5F , 0x60, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47 , 0x48, 0x49, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x4F , 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57 , 0x58, 0x59, 0x5A, 0x7B, 0x7C, 0x7D, 0x7E, 0x7F , 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87 , 0x88, 0x89, 0x8A, 0x8B, 0x8C, 0x8D, 0x8E, 0x8F , 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97 , 0x98, 0x99, 0x9A, 0x9B, 0x9C, 0x9D, 0x9E, 0x9F , 0xA0, 0xA1, 0xA2, 0xA3, 0xA4, 0xA5, 0xA6, 0xA7 , 0xA8, 0xA9, 0xAA, 0xAB, 0xAC, 0xAD, 0xAE, 0xAF , 0xB0, 0xB1, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6, 0xB7 , 0xB8, 0xB9, 0xBA, 0xBB, 0xBC, 0xBD, 0xBE, 0xBF , 0x41, 0x41, 0x41, 0x41, 0x5C, 0x5B, 0x5C, 0x43 , 0x45, 0x45, 0x45, 0x45, 0x49, 0x49, 0x49, 0x49 , 0x44, 0x4E, 0x4F, 0x4F, 0x4F, 0x4F, 0x5D, 0xD7 , 0xD8, 0x55, 0x55, 0x55, 0x59, 0x59, 0xDE, 0xDF , 0x41, 0x41, 0x41, 0x41, 0x5C, 0x5B, 0x5C, 0x43 , 0x45, 0x45, 0x45, 0x45, 0x49, 0x49, 0x49, 0x49 , 0x44, 0x4E, 0x4F, 0x4F, 0x4F, 0x4F, 0x5D, 0xF7 , 0xD8, 0x55, 0x55, 0x55, 0x59, 0x59, 0xDE, 0xFF }; ulint srv_pool_size = ULINT_MAX; /* size in database pages; MySQL originally sets this value in megabytes */ ulint srv_mem_pool_size = ULINT_MAX; /* size in bytes */ ulint srv_lock_table_size = ULINT_MAX; ulint srv_n_file_io_threads = ULINT_MAX; ibool srv_archive_recovery = 0; dulint srv_archive_recovery_limit_lsn; ulint srv_lock_wait_timeout = 1024 * 1024 * 1024; char* srv_file_flush_method_str = NULL; ulint srv_unix_file_flush_method = SRV_UNIX_FDATASYNC; ulint srv_win_file_flush_method = SRV_WIN_IO_UNBUFFERED; /* If the following is != 0 we do not allow inserts etc. This protects the user from forgetting the innodb_force_recovery keyword to my.cnf */ ulint srv_force_recovery = 0; /*-----------------------*/ /* The following controls how many threads we let inside InnoDB concurrently: threads waiting for locks are not counted into the number because otherwise we could get a deadlock. MySQL creates a thread for each user session, and semaphore contention and convoy problems can occur withput this restriction. Value 10 should be good if there are less than 4 processors + 4 disks in the computer. Bigger computers need bigger values. */ ulint srv_thread_concurrency = 8; os_fast_mutex_t srv_conc_mutex; /* this mutex protects srv_conc data structures */ lint srv_conc_n_threads = 0; /* number of OS threads currently inside InnoDB; it is not an error if this drops temporarily below zero because we do not demand that every thread increments this, but a thread waiting for a lock decrements this temporarily */ ulint srv_conc_n_waiting_threads = 0; /* number of OS threads waiting in the FIFO for a permission to enter InnoDB */ typedef struct srv_conc_slot_struct srv_conc_slot_t; struct srv_conc_slot_struct{ os_event_t event; /* event to wait */ ibool reserved; /* TRUE if slot reserved */ ibool wait_ended; /* TRUE when another thread has already set the event and the thread in this slot is free to proceed; but reserved may still be TRUE at that point */ UT_LIST_NODE_T(srv_conc_slot_t) srv_conc_queue; /* queue node */ }; UT_LIST_BASE_NODE_T(srv_conc_slot_t) srv_conc_queue; /* queue of threads waiting to get in */ srv_conc_slot_t srv_conc_slots[OS_THREAD_MAX_N]; /* array of wait slots */ /* Number of times a thread is allowed to enter InnoDB within the same SQL query after it has once got the ticket at srv_conc_enter_innodb */ #define SRV_FREE_TICKETS_TO_ENTER 500 /*-----------------------*/ /* If the following is set TRUE then we do not run purge and insert buffer merge to completion before shutdown */ ibool srv_fast_shutdown = FALSE; ibool srv_use_doublewrite_buf = TRUE; ibool srv_set_thread_priorities = TRUE; int srv_query_thread_priority = 0; /*-------------------------------------------*/ ulint srv_n_spin_wait_rounds = 20; ulint srv_spin_wait_delay = 5; ibool srv_priority_boost = TRUE; char srv_endpoint_name[COM_MAX_ADDR_LEN]; ulint srv_n_com_threads = ULINT_MAX; ulint srv_n_worker_threads = ULINT_MAX; ibool srv_print_thread_releases = FALSE; ibool srv_print_lock_waits = FALSE; ibool srv_print_buf_io = FALSE; ibool srv_print_log_io = FALSE; ibool srv_print_latch_waits = FALSE; ulint srv_n_rows_inserted = 0; ulint srv_n_rows_updated = 0; ulint srv_n_rows_deleted = 0; ulint srv_n_rows_read = 0; ulint srv_n_rows_inserted_old = 0; ulint srv_n_rows_updated_old = 0; ulint srv_n_rows_deleted_old = 0; ulint srv_n_rows_read_old = 0; /* Set the following to 0 if you want InnoDB to write messages on stderr on startup/shutdown */ ibool srv_print_verbose_log = TRUE; ibool srv_print_innodb_monitor = FALSE; ibool srv_print_innodb_lock_monitor = FALSE; ibool srv_print_innodb_tablespace_monitor = FALSE; ibool srv_print_innodb_table_monitor = FALSE; /* The parameters below are obsolete: */ ibool srv_print_parsed_sql = FALSE; ulint srv_sim_disk_wait_pct = ULINT_MAX; ulint srv_sim_disk_wait_len = ULINT_MAX; ibool srv_sim_disk_wait_by_yield = FALSE; ibool srv_sim_disk_wait_by_wait = FALSE; ibool srv_measure_contention = FALSE; ibool srv_measure_by_spin = FALSE; ibool srv_test_extra_mutexes = FALSE; ibool srv_test_nocache = FALSE; ibool srv_test_cache_evict = FALSE; ibool srv_test_sync = FALSE; ulint srv_test_n_threads = ULINT_MAX; ulint srv_test_n_loops = ULINT_MAX; ulint srv_test_n_free_rnds = ULINT_MAX; ulint srv_test_n_reserved_rnds = ULINT_MAX; ulint srv_test_array_size = ULINT_MAX; ulint srv_test_n_mutexes = ULINT_MAX; /* Array of English strings describing the current state of an i/o handler thread */ char* srv_io_thread_op_info[SRV_MAX_N_IO_THREADS]; time_t srv_last_monitor_time; mutex_t srv_innodb_monitor_mutex; ulint srv_main_thread_process_no = 0; ulint srv_main_thread_id = 0; /* IMPLEMENTATION OF THE SERVER MAIN PROGRAM ========================================= There is the following analogue between this database server and an operating system kernel: DB concept equivalent OS concept ---------- --------------------- transaction -- process; query thread -- thread; lock -- semaphore; transaction set to the rollback state -- kill signal delivered to a process; kernel -- kernel; query thread execution: (a) without kernel mutex reserved -- process executing in user mode; (b) with kernel mutex reserved -- process executing in kernel mode; The server is controlled by a master thread which runs at a priority higher than normal, that is, higher than user threads. It sleeps most of the time, and wakes up, say, every 300 milliseconds, to check whether there is anything happening in the server which requires intervention of the master thread. Such situations may be, for example, when flushing of dirty blocks is needed in the buffer pool or old version of database rows have to be cleaned away. The threads which we call user threads serve the queries of the clients and input from the console of the server. They run at normal priority. The server may have several communications endpoints. A dedicated set of user threads waits at each of these endpoints ready to receive a client request. Each request is taken by a single user thread, which then starts processing and, when the result is ready, sends it to the client and returns to wait at the same endpoint the thread started from. So, we do not have dedicated communication threads listening at the endpoints and dealing the jobs to dedicated worker threads. Our architecture saves one thread swithch per request, compared to the solution with dedicated communication threads which amounts to 15 microseconds on 100 MHz Pentium running NT. If the client is communicating over a network, this saving is negligible, but if the client resides in the same machine, maybe in an SMP machine on a different processor from the server thread, the saving can be important as the threads can communicate over shared memory with an overhead of a few microseconds. We may later implement a dedicated communication thread solution for those endpoints which communicate over a network. Our solution with user threads has two problems: for each endpoint there has to be a number of listening threads. If there are many communication endpoints, it may be difficult to set the right number of concurrent threads in the system, as many of the threads may always be waiting at less busy endpoints. Another problem is queuing of the messages, as the server internally does not offer any queue for jobs. Another group of user threads is intended for splitting the queries and processing them in parallel. Let us call these parallel communication threads. These threads are waiting for parallelized tasks, suspended on event semaphores. A single user thread waits for input from the console, like a command to shut the database. Utility threads are a different group of threads which takes care of the buffer pool flushing and other, mainly background operations, in the server. Some of these utility threads always run at a lower than normal priority, so that they are always in background. Some of them may dynamically boost their priority by the pri_adjust function, even to higher than normal priority, if their task becomes urgent. The running of utilities is controlled by high- and low-water marks of urgency. The urgency may be measured by the number of dirty blocks in the buffer pool, in the case of the flush thread, for example. When the high-water mark is exceeded, an utility starts running, until the urgency drops under the low-water mark. Then the utility thread suspend itself to wait for an event. The master thread is responsible of signaling this event when the utility thread is again needed. For each individual type of utility, some threads always remain at lower than normal priority. This is because pri_adjust is implemented so that the threads at normal or higher priority control their share of running time by calling sleep. Thus, if the load of the system sudenly drops, these threads cannot necessarily utilize the system fully. The background priority threads make up for this, starting to run when the load drops. When there is no activity in the system, also the master thread suspends itself to wait for an event making the server totally silent. The responsibility to signal this event is on the user thread which again receives a message from a client. There is still one complication in our server design. If a background utility thread obtains a resource (e.g., mutex) needed by a user thread, and there is also some other user activity in the system, the user thread may have to wait indefinitely long for the resource, as the OS does not schedule a background thread if there is some other runnable user thread. This problem is called priority inversion in real-time programming. One solution to the priority inversion problem would be to keep record of which thread owns which resource and in the above case boost the priority of the background thread so that it will be scheduled and it can release the resource. This solution is called priority inheritance in real-time programming. A drawback of this solution is that the overhead of acquiring a mutex increases slightly, maybe 0.2 microseconds on a 100 MHz Pentium, because the thread has to call os_thread_get_curr_id. This may be compared to 0.5 microsecond overhead for a mutex lock-unlock pair. Note that the thread cannot store the information in the resource, say mutex, itself, because competing threads could wipe out the information if it is stored before acquiring the mutex, and if it stored afterwards, the information is outdated for the time of one machine instruction, at least. (To be precise, the information could be stored to lock_word in mutex if the machine supports atomic swap.) The above solution with priority inheritance may become actual in the future, but at the moment we plan to implement a more coarse solution, which could be called a global priority inheritance. If a thread has to wait for a long time, say 300 milliseconds, for a resource, we just guess that it may be waiting for a resource owned by a background thread, and boost the the priority of all runnable background threads to the normal level. The background threads then themselves adjust their fixed priority back to background after releasing all resources they had (or, at some fixed points in their program code). What is the performance of the global priority inheritance solution? We may weigh the length of the wait time 300 milliseconds, during which the system processes some other thread to the cost of boosting the priority of each runnable background thread, rescheduling it, and lowering the priority again. On 100 MHz Pentium + NT this overhead may be of the order 100 microseconds per thread. So, if the number of runnable background threads is not very big, say < 100, the cost is tolerable. Utility threads probably will access resources used by user threads not very often, so collisions of user threads to preempted utility threads should not happen very often. The thread table contains information of the current status of each thread existing in the system, and also the event semaphores used in suspending the master thread and utility and parallel communication threads when they have nothing to do. The thread table can be seen as an analogue to the process table in a traditional Unix implementation. The thread table is also used in the global priority inheritance scheme. This brings in one additional complication: threads accessing the thread table must have at least normal fixed priority, because the priority inheritance solution does not work if a background thread is preempted while possessing the mutex protecting the thread table. So, if a thread accesses the thread table, its priority has to be boosted at least to normal. This priority requirement can be seen similar to the privileged mode used when processing the kernel calls in traditional Unix.*/ /* Thread slot in the thread table */ struct srv_slot_struct{ os_thread_id_t id; /* thread id */ os_thread_t handle; /* thread handle */ ulint type; /* thread type: user, utility etc. */ ibool in_use; /* TRUE if this slot is in use */ ibool suspended; /* TRUE if the thread is waiting for the event of this slot */ ib_time_t suspend_time; /* time when the thread was suspended */ os_event_t event; /* event used in suspending the thread when it has nothing to do */ que_thr_t* thr; /* suspended query thread (only used for MySQL threads) */ }; /* Table for MySQL threads where they will be suspended to wait for locks */ srv_slot_t* srv_mysql_table = NULL; os_event_t srv_lock_timeout_thread_event; srv_sys_t* srv_sys = NULL; byte srv_pad1[64]; /* padding to prevent other memory update hotspots from residing on the same memory cache line */ mutex_t* kernel_mutex_temp;/* mutex protecting the server, trx structs, query threads, and lock table */ byte srv_pad2[64]; /* padding to prevent other memory update hotspots from residing on the same memory cache line */ /* The following three values measure the urgency of the jobs of buffer, version, and insert threads. They may vary from 0 - 1000. The server mutex protects all these variables. The low-water values tell that the server can acquiesce the utility when the value drops below this low-water mark. */ ulint srv_meter[SRV_MASTER + 1]; ulint srv_meter_low_water[SRV_MASTER + 1]; ulint srv_meter_high_water[SRV_MASTER + 1]; ulint srv_meter_high_water2[SRV_MASTER + 1]; ulint srv_meter_foreground[SRV_MASTER + 1]; /* The following values give info about the activity going on in the database. They are protected by the server mutex. The arrays are indexed by the type of the thread. */ ulint srv_n_threads_active[SRV_MASTER + 1]; ulint srv_n_threads[SRV_MASTER + 1]; /************************************************************************* Accessor function to get pointer to n'th slot in the server thread table. */ static srv_slot_t* srv_table_get_nth_slot( /*===================*/ /* out: pointer to the slot */ ulint index) /* in: index of the slot */ { ut_a(index < OS_THREAD_MAX_N); return(srv_sys->threads + index); } /************************************************************************* Gets the number of threads in the system. */ ulint srv_get_n_threads(void) /*===================*/ { ulint i; ulint n_threads = 0; mutex_enter(&kernel_mutex); for (i = SRV_COM; i < SRV_MASTER + 1; i++) { n_threads += srv_n_threads[i]; } mutex_exit(&kernel_mutex); return(n_threads); } /************************************************************************* Reserves a slot in the thread table for the current thread. Also creates the thread local storage struct for the current thread. NOTE! The server mutex has to be reserved by the caller! */ static ulint srv_table_reserve_slot( /*===================*/ /* out: reserved slot index */ ulint type) /* in: type of the thread: one of SRV_COM, ... */ { srv_slot_t* slot; ulint i; ut_a(type > 0); ut_a(type <= SRV_MASTER); i = 0; slot = srv_table_get_nth_slot(i); while (slot->in_use) { i++; slot = srv_table_get_nth_slot(i); } ut_a(slot->in_use == FALSE); slot->in_use = TRUE; slot->suspended = FALSE; slot->id = os_thread_get_curr_id(); slot->handle = os_thread_get_curr(); slot->type = type; thr_local_create(); thr_local_set_slot_no(os_thread_get_curr_id(), i); return(i); } /************************************************************************* Suspends the calling thread to wait for the event in its thread slot. NOTE! The server mutex has to be reserved by the caller! */ static os_event_t srv_suspend_thread(void) /*====================*/ /* out: event for the calling thread to wait */ { srv_slot_t* slot; os_event_t event; ulint slot_no; ulint type; ut_ad(mutex_own(&kernel_mutex)); slot_no = thr_local_get_slot_no(os_thread_get_curr_id()); if (srv_print_thread_releases) { printf("Suspending thread %lu to slot %lu meter %lu\n", os_thread_get_curr_id(), slot_no, srv_meter[SRV_RECOVERY]); } slot = srv_table_get_nth_slot(slot_no); type = slot->type; ut_ad(type >= SRV_WORKER); ut_ad(type <= SRV_MASTER); event = slot->event; slot->suspended = TRUE; ut_ad(srv_n_threads_active[type] > 0); srv_n_threads_active[type]--; os_event_reset(event); return(event); } /************************************************************************* Releases threads of the type given from suspension in the thread table. NOTE! The server mutex has to be reserved by the caller! */ ulint srv_release_threads( /*================*/ /* out: number of threads released: this may be < n if not enough threads were suspended at the moment */ ulint type, /* in: thread type */ ulint n) /* in: number of threads to release */ { srv_slot_t* slot; ulint i; ulint count = 0; ut_ad(type >= SRV_WORKER); ut_ad(type <= SRV_MASTER); ut_ad(n > 0); ut_ad(mutex_own(&kernel_mutex)); for (i = 0; i < OS_THREAD_MAX_N; i++) { slot = srv_table_get_nth_slot(i); if (slot->in_use && slot->type == type && slot->suspended) { slot->suspended = FALSE; srv_n_threads_active[type]++; os_event_set(slot->event); if (srv_print_thread_releases) { printf( "Releasing thread %lu type %lu from slot %lu meter %lu\n", slot->id, type, i, srv_meter[SRV_RECOVERY]); } count++; if (count == n) { break; } } } return(count); } /************************************************************************* Returns the calling thread type. */ ulint srv_get_thread_type(void) /*=====================*/ /* out: SRV_COM, ... */ { ulint slot_no; srv_slot_t* slot; ulint type; mutex_enter(&kernel_mutex); slot_no = thr_local_get_slot_no(os_thread_get_curr_id()); slot = srv_table_get_nth_slot(slot_no); type = slot->type; ut_ad(type >= SRV_WORKER); ut_ad(type <= SRV_MASTER); mutex_exit(&kernel_mutex); return(type); } /*********************************************************************** Increments by 1 the count of active threads of the type given and releases master thread if necessary. */ static void srv_inc_thread_count( /*=================*/ ulint type) /* in: type of the thread */ { mutex_enter(&kernel_mutex); srv_activity_count++; srv_n_threads_active[type]++; if (srv_n_threads_active[SRV_MASTER] == 0) { srv_release_threads(SRV_MASTER, 1); } mutex_exit(&kernel_mutex); } /*********************************************************************** Decrements by 1 the count of active threads of the type given. */ static void srv_dec_thread_count( /*=================*/ ulint type) /* in: type of the thread */ { mutex_enter(&kernel_mutex); /* FIXME: the following assertion sometimes fails: */ if (srv_n_threads_active[type] == 0) { printf("Error: thread type %lu\n", type); ut_ad(0); } srv_n_threads_active[type]--; mutex_exit(&kernel_mutex); } /*********************************************************************** Calculates the number of allowed utility threads for a thread to decide if it has to suspend itself in the thread table. */ static ulint srv_max_n_utilities( /*================*/ /* out: maximum number of allowed utilities of the type given */ ulint type) /* in: utility type */ { ulint ret; if (srv_n_threads_active[SRV_COM] == 0) { if (srv_meter[type] > srv_meter_low_water[type]) { return(srv_n_threads[type] / 2); } else { return(0); } } else { if (srv_meter[type] < srv_meter_foreground[type]) { return(0); } ret = 1 + ((srv_n_threads[type] * (ulint)(srv_meter[type] - srv_meter_foreground[type])) / (ulint)(1000 - srv_meter_foreground[type])); if (ret > srv_n_threads[type]) { return(srv_n_threads[type]); } else { return(ret); } } } /*********************************************************************** Increments the utility meter by the value given and releases utility threads if necessary. */ void srv_increment_meter( /*================*/ ulint type, /* in: utility type */ ulint n) /* in: value to add to meter */ { ulint m; mutex_enter(&kernel_mutex); srv_meter[type] += n; m = srv_max_n_utilities(type); if (m > srv_n_threads_active[type]) { srv_release_threads(type, m - srv_n_threads_active[type]); } mutex_exit(&kernel_mutex); } /*********************************************************************** Releases max number of utility threads if no queries are active and the high-water mark for the utility is exceeded. */ void srv_release_max_if_no_queries(void) /*===============================*/ { ulint m; ulint type; mutex_enter(&kernel_mutex); if (srv_n_threads_active[SRV_COM] > 0) { mutex_exit(&kernel_mutex); return; } type = SRV_RECOVERY; m = srv_n_threads[type] / 2; if ((srv_meter[type] > srv_meter_high_water[type]) && (srv_n_threads_active[type] < m)) { srv_release_threads(type, m - srv_n_threads_active[type]); printf("Releasing max background\n"); } mutex_exit(&kernel_mutex); } /*********************************************************************** Releases one utility thread if no queries are active and the high-water mark 2 for the utility is exceeded. */ static void srv_release_one_if_no_queries(void) /*===============================*/ { ulint m; ulint type; mutex_enter(&kernel_mutex); if (srv_n_threads_active[SRV_COM] > 0) { mutex_exit(&kernel_mutex); return; } type = SRV_RECOVERY; m = 1; if ((srv_meter[type] > srv_meter_high_water2[type]) && (srv_n_threads_active[type] < m)) { srv_release_threads(type, m - srv_n_threads_active[type]); printf("Releasing one background\n"); } mutex_exit(&kernel_mutex); } #ifdef notdefined /*********************************************************************** Decrements the utility meter by the value given and suspends the calling thread, which must be an utility thread of the type given, if necessary. */ static void srv_decrement_meter( /*================*/ ulint type, /* in: utility type */ ulint n) /* in: value to subtract from meter */ { ulint opt; os_event_t event; mutex_enter(&kernel_mutex); if (srv_meter[type] < n) { srv_meter[type] = 0; } else { srv_meter[type] -= n; } opt = srv_max_n_utilities(type); if (opt < srv_n_threads_active[type]) { event = srv_suspend_thread(); mutex_exit(&kernel_mutex); os_event_wait(event); } else { mutex_exit(&kernel_mutex); } } #endif /************************************************************************* Implements the server console. */ ulint srv_console( /*========*/ /* out: return code, not used */ void* arg) /* in: argument, not used */ { char command[256]; UT_NOT_USED(arg); mutex_enter(&kernel_mutex); srv_table_reserve_slot(SRV_CONSOLE); mutex_exit(&kernel_mutex); os_event_wait(srv_sys->operational); for (;;) { scanf("%s", command); srv_inc_thread_count(SRV_CONSOLE); if (command[0] == 'c') { printf("Making checkpoint\n"); log_make_checkpoint_at(ut_dulint_max, TRUE); printf("Checkpoint completed\n"); } else if (command[0] == 'd') { srv_sim_disk_wait_pct = atoi(command + 1); printf( "Starting disk access simulation with pct %lu\n", srv_sim_disk_wait_pct); } else { printf("\nNot supported!\n"); } srv_dec_thread_count(SRV_CONSOLE); } return(0); } /************************************************************************* Creates the first communication endpoint for the server. This first call also initializes the com0com.* module. */ void srv_communication_init( /*===================*/ char* endpoint) /* in: server address */ { ulint ret; ulint len; srv_sys->endpoint = com_endpoint_create(COM_SHM); ut_a(srv_sys->endpoint); len = ODBC_DATAGRAM_SIZE; ret = com_endpoint_set_option(srv_sys->endpoint, COM_OPT_MAX_DGRAM_SIZE, (byte*)&len, sizeof(ulint)); ut_a(ret == 0); ret = com_bind(srv_sys->endpoint, endpoint, ut_strlen(endpoint)); ut_a(ret == 0); } /************************************************************************* Implements the recovery utility. */ static ulint srv_recovery_thread( /*================*/ /* out: return code, not used */ void* arg) /* in: not used */ { ulint slot_no; os_event_t event; UT_NOT_USED(arg); slot_no = srv_table_reserve_slot(SRV_RECOVERY); os_event_wait(srv_sys->operational); for (;;) { /* Finish a possible recovery */ srv_inc_thread_count(SRV_RECOVERY); /* recv_recovery_from_checkpoint_finish(); */ srv_dec_thread_count(SRV_RECOVERY); mutex_enter(&kernel_mutex); event = srv_suspend_thread(); mutex_exit(&kernel_mutex); /* Wait for somebody to release this thread; (currently, this should never be released) */ os_event_wait(event); } return(0); } /************************************************************************* Implements the purge utility. */ ulint srv_purge_thread( /*=============*/ /* out: return code, not used */ void* arg) /* in: not used */ { UT_NOT_USED(arg); os_event_wait(srv_sys->operational); for (;;) { trx_purge(); } return(0); } /************************************************************************* Creates the utility threads. */ void srv_create_utility_threads(void) /*============================*/ { /* os_thread_t thread; os_thread_id_t thr_id; */ ulint i; mutex_enter(&kernel_mutex); srv_n_threads[SRV_RECOVERY] = 1; srv_n_threads_active[SRV_RECOVERY] = 1; mutex_exit(&kernel_mutex); for (i = 0; i < 1; i++) { /* thread = os_thread_create(srv_recovery_thread, NULL, &thr_id); */ /* ut_a(thread); */ } /* thread = os_thread_create(srv_purge_thread, NULL, &thr_id); ut_a(thread); */ } /************************************************************************* Implements the communication threads. */ static ulint srv_com_thread( /*===========*/ /* out: return code; not used */ void* arg) /* in: not used */ { byte* msg_buf; byte* addr_buf; ulint msg_len; ulint addr_len; ulint ret; UT_NOT_USED(arg); srv_table_reserve_slot(SRV_COM); os_event_wait(srv_sys->operational); msg_buf = mem_alloc(com_endpoint_get_max_size(srv_sys->endpoint)); addr_buf = mem_alloc(COM_MAX_ADDR_LEN); for (;;) { ret = com_recvfrom(srv_sys->endpoint, msg_buf, com_endpoint_get_max_size(srv_sys->endpoint), &msg_len, (char*)addr_buf, COM_MAX_ADDR_LEN, &addr_len); ut_a(ret == 0); srv_inc_thread_count(SRV_COM); sess_process_cli_msg(msg_buf, msg_len, addr_buf, addr_len); /* srv_increment_meter(SRV_RECOVERY, 1); */ srv_dec_thread_count(SRV_COM); /* Release one utility thread for each utility if high water mark 2 is exceeded and there are no active queries. This is done to utilize possible quiet time in the server. */ srv_release_one_if_no_queries(); } return(0); } /************************************************************************* Creates the communication threads. */ void srv_create_com_threads(void) /*========================*/ { /* os_thread_t thread; os_thread_id_t thr_id; */ ulint i; srv_n_threads[SRV_COM] = srv_n_com_threads; for (i = 0; i < srv_n_com_threads; i++) { /* thread = os_thread_create(srv_com_thread, NULL, &thr_id); */ /* ut_a(thread); */ } } /************************************************************************* Implements the worker threads. */ static ulint srv_worker_thread( /*==============*/ /* out: return code, not used */ void* arg) /* in: not used */ { os_event_t event; UT_NOT_USED(arg); srv_table_reserve_slot(SRV_WORKER); os_event_wait(srv_sys->operational); for (;;) { mutex_enter(&kernel_mutex); event = srv_suspend_thread(); mutex_exit(&kernel_mutex); /* Wait for somebody to release this thread */ os_event_wait(event); srv_inc_thread_count(SRV_WORKER); /* Check in the server task queue if there is work for this thread, and do the work */ srv_que_task_queue_check(); srv_dec_thread_count(SRV_WORKER); /* Release one utility thread for each utility if high water mark 2 is exceeded and there are no active queries. This is done to utilize possible quiet time in the server. */ srv_release_one_if_no_queries(); } return(0); } /************************************************************************* Creates the worker threads. */ void srv_create_worker_threads(void) /*===========================*/ { /* os_thread_t thread; os_thread_id_t thr_id; */ ulint i; srv_n_threads[SRV_WORKER] = srv_n_worker_threads; srv_n_threads_active[SRV_WORKER] = srv_n_worker_threads; for (i = 0; i < srv_n_worker_threads; i++) { /* thread = os_thread_create(srv_worker_thread, NULL, &thr_id); */ /* ut_a(thread); */ } } #ifdef notdefined /************************************************************************* Reads a keyword and a value from a file. */ ulint srv_read_init_val( /*==============*/ /* out: DB_SUCCESS or error code */ FILE* initfile, /* in: file pointer */ char* keyword, /* in: keyword before value(s), or NULL if no keyword read */ char* str_buf, /* in/out: buffer for a string value to read, buffer size must be 10000 bytes, if NULL then not read */ ulint* num_val, /* out: numerical value to read, if NULL then not read */ ibool print_not_err) /* in: if TRUE, then we will not print error messages to console */ { ulint ret; char scan_buf[10000]; if (keyword == NULL) { goto skip_keyword; } ret = fscanf(initfile, "%9999s", scan_buf); if (ret == 0 || ret == EOF || 0 != ut_strcmp(scan_buf, keyword)) { if (print_not_err) { return(DB_ERROR); } printf("Error in InnoDB booting: keyword %s not found\n", keyword); printf("from the initfile!\n"); return(DB_ERROR); } skip_keyword: if (num_val == NULL && str_buf == NULL) { return(DB_SUCCESS); } ret = fscanf(initfile, "%9999s", scan_buf); if (ret == EOF || ret == 0) { if (print_not_err) { return(DB_ERROR); } printf( "Error in InnoDB booting: could not read first value after %s\n", keyword); printf("from the initfile!\n"); return(DB_ERROR); } if (str_buf) { ut_memcpy(str_buf, scan_buf, 10000); printf("init keyword %s value %s read\n", keyword, str_buf); if (!num_val) { return(DB_SUCCESS); } ret = fscanf(initfile, "%9999s", scan_buf); if (ret == EOF || ret == 0) { if (print_not_err) { return(DB_ERROR); } printf( "Error in InnoDB booting: could not read second value after %s\n", keyword); printf("from the initfile!\n"); return(DB_ERROR); } } if (ut_strlen(scan_buf) > 9) { if (print_not_err) { return(DB_ERROR); } printf( "Error in InnoDB booting: numerical value too big after %s\n", keyword); printf("in the initfile!\n"); return(DB_ERROR); } *num_val = (ulint)atoi(scan_buf); if (*num_val >= 1000000000) { if (print_not_err) { return(DB_ERROR); } printf( "Error in InnoDB booting: numerical value too big after %s\n", keyword); printf("in the initfile!\n"); return(DB_ERROR); } printf("init keyword %s value %lu read\n", keyword, *num_val); return(DB_SUCCESS); } /************************************************************************* Reads keywords and values from an initfile. */ ulint srv_read_initfile( /*==============*/ /* out: DB_SUCCESS or error code */ FILE* initfile) /* in: file pointer */ { char str_buf[10000]; ulint n; ulint i; ulint ulint_val; ulint val1; ulint val2; ulint err; err = srv_read_init_val(initfile, "INNOBASE_DATA_HOME_DIR", str_buf, NULL, FALSE); if (err != DB_SUCCESS) return(err); srv_data_home = ut_malloc(ut_strlen(str_buf) + 1); ut_memcpy(srv_data_home, str_buf, ut_strlen(str_buf) + 1); err = srv_read_init_val(initfile,"TABLESPACE_NUMBER_OF_DATA_FILES", NULL, &n, FALSE); if (err != DB_SUCCESS) return(err); srv_n_data_files = n; srv_data_file_names = ut_malloc(n * sizeof(char*)); srv_data_file_sizes = ut_malloc(n * sizeof(ulint)); for (i = 0; i < n; i++) { err = srv_read_init_val(initfile, "DATA_FILE_PATH_AND_SIZE_MB", str_buf, &ulint_val, FALSE); if (err != DB_SUCCESS) return(err); srv_data_file_names[i] = ut_malloc(ut_strlen(str_buf) + 1); ut_memcpy(srv_data_file_names[i], str_buf, ut_strlen(str_buf) + 1); srv_data_file_sizes[i] = ulint_val * ((1024 * 1024) / UNIV_PAGE_SIZE); } err = srv_read_init_val(initfile, "NUMBER_OF_MIRRORED_LOG_GROUPS", NULL, &srv_n_log_groups, FALSE); if (err != DB_SUCCESS) return(err); err = srv_read_init_val(initfile, "NUMBER_OF_LOG_FILES_IN_GROUP", NULL, &srv_n_log_files, FALSE); if (err != DB_SUCCESS) return(err); err = srv_read_init_val(initfile, "LOG_FILE_SIZE_KB", NULL, &srv_log_file_size, FALSE); if (err != DB_SUCCESS) return(err); srv_log_file_size = srv_log_file_size / (UNIV_PAGE_SIZE / 1024); srv_log_group_home_dirs = ut_malloc(srv_n_log_files * sizeof(char*)); for (i = 0; i < srv_n_log_groups; i++) { err = srv_read_init_val(initfile, "INNOBASE_LOG_GROUP_HOME_DIR", str_buf, NULL, FALSE); if (err != DB_SUCCESS) return(err); srv_log_group_home_dirs[i] = ut_malloc(ut_strlen(str_buf) + 1); ut_memcpy(srv_log_group_home_dirs[i], str_buf, ut_strlen(str_buf) + 1); } err = srv_read_init_val(initfile, "INNOBASE_LOG_ARCH_DIR", str_buf, NULL, FALSE); if (err != DB_SUCCESS) return(err); srv_arch_dir = ut_malloc(ut_strlen(str_buf) + 1); ut_memcpy(srv_arch_dir, str_buf, ut_strlen(str_buf) + 1); err = srv_read_init_val(initfile, "LOG_ARCHIVE_ON(1/0)", NULL, &srv_log_archive_on, FALSE); if (err != DB_SUCCESS) return(err); err = srv_read_init_val(initfile, "LOG_BUFFER_SIZE_KB", NULL, &srv_log_buffer_size, FALSE); if (err != DB_SUCCESS) return(err); srv_log_buffer_size = srv_log_buffer_size / (UNIV_PAGE_SIZE / 1024); err = srv_read_init_val(initfile, "FLUSH_LOG_AT_TRX_COMMIT(1/0)", NULL, &srv_flush_log_at_trx_commit, FALSE); if (err != DB_SUCCESS) return(err); err = srv_read_init_val(initfile, "BUFFER_POOL_SIZE_MB", NULL, &srv_pool_size, FALSE); if (err != DB_SUCCESS) return(err); srv_pool_size = srv_pool_size * ((1024 * 1024) / UNIV_PAGE_SIZE); err = srv_read_init_val(initfile, "ADDITIONAL_MEM_POOL_SIZE_MB", NULL, &srv_mem_pool_size, FALSE); if (err != DB_SUCCESS) return(err); srv_mem_pool_size = srv_mem_pool_size * 1024 * 1024; srv_lock_table_size = 20 * srv_pool_size; err = srv_read_init_val(initfile, "NUMBER_OF_FILE_IO_THREADS", NULL, &srv_n_file_io_threads, FALSE); if (err != DB_SUCCESS) return(err); err = srv_read_init_val(initfile, "SRV_RECOVER_FROM_BACKUP", NULL, NULL, TRUE); if (err == DB_SUCCESS) { srv_archive_recovery = TRUE; srv_archive_recovery_limit_lsn = ut_dulint_max; err = srv_read_init_val(initfile, NULL, NULL, &val1, TRUE); err = srv_read_init_val(initfile, NULL, NULL, &val2, TRUE); if (err == DB_SUCCESS) { srv_archive_recovery_limit_lsn = ut_dulint_create(val1, val2); } } /* err = srv_read_init_val(initfile, "SYNC_NUMBER_OF_SPIN_WAIT_ROUNDS", NULL, &srv_n_spin_wait_rounds); err = srv_read_init_val(initfile, "SYNC_SPIN_WAIT_DELAY", NULL, &srv_spin_wait_delay); */ return(DB_SUCCESS); } /************************************************************************* Reads keywords and a values from an initfile. In case of an error, exits from the process. */ void srv_read_initfile( /*==============*/ FILE* initfile) /* in: file pointer */ { char str_buf[10000]; ulint ulint_val; srv_read_init_val(initfile, FALSE, "SRV_ENDPOINT_NAME", str_buf, &ulint_val); ut_a(ut_strlen(str_buf) < COM_MAX_ADDR_LEN); ut_memcpy(srv_endpoint_name, str_buf, COM_MAX_ADDR_LEN); srv_read_init_val(initfile, TRUE, "SRV_N_COM_THREADS", str_buf, &srv_n_com_threads); srv_read_init_val(initfile, TRUE, "SRV_N_WORKER_THREADS", str_buf, &srv_n_worker_threads); srv_read_init_val(initfile, TRUE, "SYNC_N_SPIN_WAIT_ROUNDS", str_buf, &srv_n_spin_wait_rounds); srv_read_init_val(initfile, TRUE, "SYNC_SPIN_WAIT_DELAY", str_buf, &srv_spin_wait_delay); srv_read_init_val(initfile, TRUE, "THREAD_PRIORITY_BOOST", str_buf, &srv_priority_boost); srv_read_init_val(initfile, TRUE, "N_SPACES", str_buf, &srv_n_spaces); srv_read_init_val(initfile, TRUE, "N_FILES", str_buf, &srv_n_files); srv_read_init_val(initfile, TRUE, "FILE_SIZE", str_buf, &srv_file_size); srv_read_init_val(initfile, TRUE, "N_LOG_GROUPS", str_buf, &srv_n_log_groups); srv_read_init_val(initfile, TRUE, "N_LOG_FILES", str_buf, &srv_n_log_files); srv_read_init_val(initfile, TRUE, "LOG_FILE_SIZE", str_buf, &srv_log_file_size); srv_read_init_val(initfile, TRUE, "LOG_ARCHIVE_ON", str_buf, &srv_log_archive_on); srv_read_init_val(initfile, TRUE, "LOG_BUFFER_SIZE", str_buf, &srv_log_buffer_size); srv_read_init_val(initfile, TRUE, "FLUSH_LOG_AT_TRX_COMMIT", str_buf, &srv_flush_log_at_trx_commit); srv_read_init_val(initfile, TRUE, "POOL_SIZE", str_buf, &srv_pool_size); srv_read_init_val(initfile, TRUE, "MEM_POOL_SIZE", str_buf, &srv_mem_pool_size); srv_read_init_val(initfile, TRUE, "LOCK_TABLE_SIZE", str_buf, &srv_lock_table_size); srv_read_init_val(initfile, TRUE, "SIM_DISK_WAIT_PCT", str_buf, &srv_sim_disk_wait_pct); srv_read_init_val(initfile, TRUE, "SIM_DISK_WAIT_LEN", str_buf, &srv_sim_disk_wait_len); srv_read_init_val(initfile, TRUE, "SIM_DISK_WAIT_BY_YIELD", str_buf, &srv_sim_disk_wait_by_yield); srv_read_init_val(initfile, TRUE, "SIM_DISK_WAIT_BY_WAIT", str_buf, &srv_sim_disk_wait_by_wait); srv_read_init_val(initfile, TRUE, "MEASURE_CONTENTION", str_buf, &srv_measure_contention); srv_read_init_val(initfile, TRUE, "MEASURE_BY_SPIN", str_buf, &srv_measure_by_spin); srv_read_init_val(initfile, TRUE, "PRINT_THREAD_RELEASES", str_buf, &srv_print_thread_releases); srv_read_init_val(initfile, TRUE, "PRINT_LOCK_WAITS", str_buf, &srv_print_lock_waits); if (srv_print_lock_waits) { lock_print_waits = TRUE; } srv_read_init_val(initfile, TRUE, "PRINT_BUF_IO", str_buf, &srv_print_buf_io); if (srv_print_buf_io) { buf_debug_prints = TRUE; } srv_read_init_val(initfile, TRUE, "PRINT_LOG_IO", str_buf, &srv_print_log_io); if (srv_print_log_io) { log_debug_writes = TRUE; } srv_read_init_val(initfile, TRUE, "PRINT_PARSED_SQL", str_buf, &srv_print_parsed_sql); if (srv_print_parsed_sql) { pars_print_lexed = TRUE; } srv_read_init_val(initfile, TRUE, "PRINT_LATCH_WAITS", str_buf, &srv_print_latch_waits); srv_read_init_val(initfile, TRUE, "TEST_EXTRA_MUTEXES", str_buf, &srv_test_extra_mutexes); srv_read_init_val(initfile, TRUE, "TEST_NOCACHE", str_buf, &srv_test_nocache); srv_read_init_val(initfile, TRUE, "TEST_CACHE_EVICT", str_buf, &srv_test_cache_evict); srv_read_init_val(initfile, TRUE, "TEST_SYNC", str_buf, &srv_test_sync); srv_read_init_val(initfile, TRUE, "TEST_N_THREADS", str_buf, &srv_test_n_threads); srv_read_init_val(initfile, TRUE, "TEST_N_LOOPS", str_buf, &srv_test_n_loops); srv_read_init_val(initfile, TRUE, "TEST_N_FREE_RNDS", str_buf, &srv_test_n_free_rnds); srv_read_init_val(initfile, TRUE, "TEST_N_RESERVED_RNDS", str_buf, &srv_test_n_reserved_rnds); srv_read_init_val(initfile, TRUE, "TEST_N_MUTEXES", str_buf, &srv_test_n_mutexes); srv_read_init_val(initfile, TRUE, "TEST_ARRAY_SIZE", str_buf, &srv_test_array_size); } #endif /************************************************************************* Initializes the server. */ void srv_init(void) /*==========*/ { srv_conc_slot_t* conc_slot; srv_slot_t* slot; ulint i; srv_sys = mem_alloc(sizeof(srv_sys_t)); kernel_mutex_temp = mem_alloc(sizeof(mutex_t)); mutex_create(&kernel_mutex); mutex_set_level(&kernel_mutex, SYNC_KERNEL); mutex_create(&srv_innodb_monitor_mutex); mutex_set_level(&srv_innodb_monitor_mutex, SYNC_NO_ORDER_CHECK); srv_sys->threads = mem_alloc(OS_THREAD_MAX_N * sizeof(srv_slot_t)); for (i = 0; i < OS_THREAD_MAX_N; i++) { slot = srv_table_get_nth_slot(i); slot->in_use = FALSE; slot->type=0; /* Avoid purify errors */ slot->event = os_event_create(NULL); ut_a(slot->event); } srv_mysql_table = mem_alloc(OS_THREAD_MAX_N * sizeof(srv_slot_t)); for (i = 0; i < OS_THREAD_MAX_N; i++) { slot = srv_mysql_table + i; slot->in_use = FALSE; slot->type = 0; slot->event = os_event_create(NULL); ut_a(slot->event); } srv_lock_timeout_thread_event = os_event_create(NULL); for (i = 0; i < SRV_MASTER + 1; i++) { srv_n_threads_active[i] = 0; srv_n_threads[i] = 0; srv_meter[i] = 30; srv_meter_low_water[i] = 50; srv_meter_high_water[i] = 100; srv_meter_high_water2[i] = 200; srv_meter_foreground[i] = 250; } srv_sys->operational = os_event_create(NULL); ut_a(srv_sys->operational); UT_LIST_INIT(srv_sys->tasks); /* Init the server concurrency restriction data structures */ os_fast_mutex_init(&srv_conc_mutex); UT_LIST_INIT(srv_conc_queue); for (i = 0; i < OS_THREAD_MAX_N; i++) { conc_slot = srv_conc_slots + i; conc_slot->reserved = FALSE; conc_slot->event = os_event_create(NULL); ut_a(conc_slot->event); } } /************************************************************************* Initializes the synchronization primitives, memory system, and the thread local storage. */ void srv_general_init(void) /*==================*/ { sync_init(); mem_init(srv_mem_pool_size); thr_local_init(); } #if defined(__NETWARE__) || defined(SAFE_MUTEX_DETECT_DESTROY) /* NetWare requires some cleanup of mutexes */ /************************************************************************* Deinitializes the synchronization primitives, memory system, and the thread local storage. */ void srv_general_free(void) /*==================*/ { sync_close(); } #endif /* __NETWARE__ */ /*======================= InnoDB Server FIFO queue =======================*/ #if defined(__NETWARE__) || defined(SAFE_MUTEX_DETECT_DESTROY) /* NetWare requires some cleanup of mutexes */ /************************************************************************* Deinitializes the server. */ void srv_free(void) /*==========*/ { srv_conc_slot_t* conc_slot; srv_slot_t* slot; ulint i; for (i = 0; i < OS_THREAD_MAX_N; i++) { slot = srv_table_get_nth_slot(i); os_event_free(slot->event); } /* TODO: free(srv_sys->threads); */ for (i = 0; i < OS_THREAD_MAX_N; i++) { slot = srv_mysql_table + i; os_event_free(slot->event); } /* TODO: free(srv_mysql_table); */ for (i = 0; i < OS_THREAD_MAX_N; i++) { conc_slot = srv_conc_slots + i; os_event_free(conc_slot->event); } } #endif /* __NETWARE__ */ /************************************************************************* Puts an OS thread to wait if there are too many concurrent threads (>= srv_thread_concurrency) inside InnoDB. The threads wait in a FIFO queue. */ void srv_conc_enter_innodb( /*==================*/ trx_t* trx) /* in: transaction object associated with the thread */ { ibool has_slept = FALSE; srv_conc_slot_t* slot; ulint i; char err_buf[1000]; if (srv_thread_concurrency >= 500) { /* Disable the concurrency check */ return; } /* If trx has 'free tickets' to enter the engine left, then use one such ticket */ if (trx->n_tickets_to_enter_innodb > 0) { trx->n_tickets_to_enter_innodb--; return; } retry: os_fast_mutex_lock(&srv_conc_mutex); if (trx->declared_to_be_inside_innodb) { ut_print_timestamp(stderr); trx_print(err_buf, trx); fprintf(stderr, " InnoDB: Error: trying to declare trx to enter InnoDB, but\n" "InnoDB: it already is declared.\n%s\n", err_buf); } if (srv_conc_n_threads < (lint)srv_thread_concurrency) { srv_conc_n_threads++; trx->declared_to_be_inside_innodb = TRUE; trx->n_tickets_to_enter_innodb = SRV_FREE_TICKETS_TO_ENTER; os_fast_mutex_unlock(&srv_conc_mutex); return; } /* If the transaction is not holding resources, let it sleep for 100 milliseconds, and try again then */ if (!has_slept && !trx->has_search_latch && NULL == UT_LIST_GET_FIRST(trx->trx_locks)) { has_slept = TRUE; /* We let is sleep only once to avoid starvation */ os_fast_mutex_unlock(&srv_conc_mutex); os_thread_sleep(100000); goto retry; } /* Too many threads inside: put the current thread to a queue */ for (i = 0; i < OS_THREAD_MAX_N; i++) { slot = srv_conc_slots + i; if (!slot->reserved) { break; } } if (i == OS_THREAD_MAX_N) { /* Could not find a free wait slot, we must let the thread enter */ srv_conc_n_threads++; trx->declared_to_be_inside_innodb = TRUE; trx->n_tickets_to_enter_innodb = 0; os_fast_mutex_unlock(&srv_conc_mutex); return; } /* Release possible search system latch this thread has */ if (trx->has_search_latch) { trx_search_latch_release_if_reserved(trx); } /* Add to the queue */ slot->reserved = TRUE; slot->wait_ended = FALSE; UT_LIST_ADD_LAST(srv_conc_queue, srv_conc_queue, slot); os_event_reset(slot->event); srv_conc_n_waiting_threads++; os_fast_mutex_unlock(&srv_conc_mutex); /* Go to wait for the event; when a thread leaves InnoDB it will release this thread */ trx->op_info = (char*)"waiting in InnoDB queue"; os_event_wait(slot->event); trx->op_info = (char*)""; os_fast_mutex_lock(&srv_conc_mutex); srv_conc_n_waiting_threads--; /* NOTE that the thread which released this thread already incremented the thread counter on behalf of this thread */ slot->reserved = FALSE; UT_LIST_REMOVE(srv_conc_queue, srv_conc_queue, slot); trx->declared_to_be_inside_innodb = TRUE; trx->n_tickets_to_enter_innodb = SRV_FREE_TICKETS_TO_ENTER; os_fast_mutex_unlock(&srv_conc_mutex); } /************************************************************************* This lets a thread enter InnoDB regardless of the number of threads inside InnoDB. This must be called when a thread ends a lock wait. */ void srv_conc_force_enter_innodb( /*========================*/ trx_t* trx) /* in: transaction object associated with the thread */ { if (srv_thread_concurrency >= 500) { return; } os_fast_mutex_lock(&srv_conc_mutex); srv_conc_n_threads++; trx->declared_to_be_inside_innodb = TRUE; trx->n_tickets_to_enter_innodb = 0; os_fast_mutex_unlock(&srv_conc_mutex); } /************************************************************************* This must be called when a thread exits InnoDB in a lock wait or at the end of an SQL statement. */ void srv_conc_force_exit_innodb( /*=======================*/ trx_t* trx) /* in: transaction object associated with the thread */ { srv_conc_slot_t* slot = NULL; if (srv_thread_concurrency >= 500) { return; } if (trx->declared_to_be_inside_innodb == FALSE) { return; } os_fast_mutex_lock(&srv_conc_mutex); srv_conc_n_threads--; trx->declared_to_be_inside_innodb = FALSE; trx->n_tickets_to_enter_innodb = 0; if (srv_conc_n_threads < (lint)srv_thread_concurrency) { /* Look for a slot where a thread is waiting and no other thread has yet released the thread */ slot = UT_LIST_GET_FIRST(srv_conc_queue); while (slot && slot->wait_ended == TRUE) { slot = UT_LIST_GET_NEXT(srv_conc_queue, slot); } if (slot != NULL) { slot->wait_ended = TRUE; /* We increment the count on behalf of the released thread */ srv_conc_n_threads++; } } os_fast_mutex_unlock(&srv_conc_mutex); if (slot != NULL) { os_event_set(slot->event); } } /************************************************************************* This must be called when a thread exits InnoDB. */ void srv_conc_exit_innodb( /*=================*/ trx_t* trx) /* in: transaction object associated with the thread */ { if (srv_thread_concurrency >= 500) { return; } if (trx->n_tickets_to_enter_innodb > 0) { /* We will pretend the thread is still inside InnoDB though it now leaves the InnoDB engine. In this way we save a lot of semaphore operations. srv_conc_force_exit_innodb is used to declare the thread definitely outside InnoDB. It should be called when there is a lock wait or an SQL statement ends. */ return; } srv_conc_force_exit_innodb(trx); } /*========================================================================*/ /************************************************************************* Normalizes init parameter values to use units we use inside InnoDB. */ static ulint srv_normalize_init_values(void) /*===========================*/ /* out: DB_SUCCESS or error code */ { ulint n; ulint i; n = srv_n_data_files; for (i = 0; i < n; i++) { srv_data_file_sizes[i] = srv_data_file_sizes[i] * ((1024 * 1024) / UNIV_PAGE_SIZE); } srv_last_file_size_max = srv_last_file_size_max * ((1024 * 1024) / UNIV_PAGE_SIZE); srv_log_file_size = srv_log_file_size / UNIV_PAGE_SIZE; srv_log_buffer_size = srv_log_buffer_size / UNIV_PAGE_SIZE; srv_pool_size = srv_pool_size / UNIV_PAGE_SIZE; srv_lock_table_size = 20 * srv_pool_size; return(DB_SUCCESS); } /************************************************************************* Boots the InnoDB server. */ ulint srv_boot(void) /*==========*/ /* out: DB_SUCCESS or error code */ { ulint err; /* Transform the init parameter values given by MySQL to use units we use inside InnoDB: */ err = srv_normalize_init_values(); if (err != DB_SUCCESS) { return(err); } /* Initialize synchronization primitives, memory management, and thread local storage */ srv_general_init(); /* Initialize this module */ srv_init(); return(DB_SUCCESS); } /************************************************************************* Reserves a slot in the thread table for the current MySQL OS thread. NOTE! The kernel mutex has to be reserved by the caller! */ static srv_slot_t* srv_table_reserve_slot_for_mysql(void) /*==================================*/ /* out: reserved slot */ { srv_slot_t* slot; ulint i; ut_ad(mutex_own(&kernel_mutex)); i = 0; slot = srv_mysql_table + i; while (slot->in_use) { i++; if (i >= OS_THREAD_MAX_N) { ut_print_timestamp(stderr); fprintf(stderr, " InnoDB: There appear to be %lu MySQL threads currently waiting\n" "InnoDB: inside InnoDB, which is the upper limit. Cannot continue operation.\n" "InnoDB: We intentionally generate a seg fault to print a stack trace\n" "InnoDB: on Linux. But first we print a list of waiting threads.\n", i); for (i = 0; i < OS_THREAD_MAX_N; i++) { slot = srv_mysql_table + i; fprintf(stderr, "Slot %lu: thread id %lu, type %lu, in use %lu, susp %lu, time %lu\n", i, os_thread_pf(slot->id), slot->type, slot->in_use, slot->suspended, (ulint)difftime(ut_time(), slot->suspend_time)); } ut_a(0); } slot = srv_mysql_table + i; } ut_a(slot->in_use == FALSE); slot->in_use = TRUE; slot->id = os_thread_get_curr_id(); slot->handle = os_thread_get_curr(); return(slot); } /******************************************************************* Puts a MySQL OS thread to wait for a lock to be released. If an error occurs during the wait trx->error_state associated with thr is != DB_SUCCESS when we return. DB_LOCK_WAIT_TIMEOUT and DB_DEADLOCK are possible errors. DB_DEADLOCK is returned if selective deadlock resolution chose this transaction as a victim. */ void srv_suspend_mysql_thread( /*=====================*/ que_thr_t* thr) /* in: query thread associated with the MySQL OS thread */ { srv_slot_t* slot; os_event_t event; double wait_time; trx_t* trx; ibool had_dict_lock = FALSE; ut_ad(!mutex_own(&kernel_mutex)); trx = thr_get_trx(thr); os_event_set(srv_lock_timeout_thread_event); mutex_enter(&kernel_mutex); trx->error_state = DB_SUCCESS; if (thr->state == QUE_THR_RUNNING) { ut_ad(thr->is_active == TRUE); /* The lock has already been released or this transaction was chosen as a deadlock victim: no need to suspend */ if (trx->was_chosen_as_deadlock_victim) { trx->error_state = DB_DEADLOCK; trx->was_chosen_as_deadlock_victim = FALSE; } mutex_exit(&kernel_mutex); return; } ut_ad(thr->is_active == FALSE); slot = srv_table_reserve_slot_for_mysql(); event = slot->event; slot->thr = thr; os_event_reset(event); slot->suspend_time = ut_time(); /* Wake the lock timeout monitor thread, if it is suspended */ os_event_set(srv_lock_timeout_thread_event); mutex_exit(&kernel_mutex); /* We must declare this OS thread to exit InnoDB, since a possible other thread holding a lock which this thread waits for must be allowed to enter, sooner or later */ srv_conc_force_exit_innodb(thr_get_trx(thr)); /* Release possible foreign key check latch */ if (trx->dict_operation_lock_mode == RW_S_LATCH) { had_dict_lock = TRUE; row_mysql_unfreeze_data_dictionary(trx); } ut_a(trx->dict_operation_lock_mode == 0); /* Wait for the release */ os_event_wait(event); if (had_dict_lock) { row_mysql_freeze_data_dictionary(trx); } /* Return back inside InnoDB */ srv_conc_force_enter_innodb(thr_get_trx(thr)); mutex_enter(&kernel_mutex); /* Release the slot for others to use */ slot->in_use = FALSE; wait_time = ut_difftime(ut_time(), slot->suspend_time); if (trx->was_chosen_as_deadlock_victim) { trx->error_state = DB_DEADLOCK; trx->was_chosen_as_deadlock_victim = FALSE; } mutex_exit(&kernel_mutex); if (srv_lock_wait_timeout < 100000000 && wait_time > (double)srv_lock_wait_timeout) { trx->error_state = DB_LOCK_WAIT_TIMEOUT; } } /************************************************************************ Releases a MySQL OS thread waiting for a lock to be released, if the thread is already suspended. */ void srv_release_mysql_thread_if_suspended( /*==================================*/ que_thr_t* thr) /* in: query thread associated with the MySQL OS thread */ { srv_slot_t* slot; ulint i; ut_ad(mutex_own(&kernel_mutex)); for (i = 0; i < OS_THREAD_MAX_N; i++) { slot = srv_mysql_table + i; if (slot->in_use && slot->thr == thr) { /* Found */ os_event_set(slot->event); return; } } /* not found */ } /********************************************************************** Refreshes the values used to calculate per-second averages. */ static void srv_refresh_innodb_monitor_stats(void) /*==================================*/ { mutex_enter(&srv_innodb_monitor_mutex); srv_last_monitor_time = time(NULL); os_aio_refresh_stats(); btr_cur_n_sea_old = btr_cur_n_sea; btr_cur_n_non_sea_old = btr_cur_n_non_sea; log_refresh_stats(); buf_refresh_io_stats(); srv_n_rows_inserted_old = srv_n_rows_inserted; srv_n_rows_updated_old = srv_n_rows_updated; srv_n_rows_deleted_old = srv_n_rows_deleted; srv_n_rows_read_old = srv_n_rows_read; mutex_exit(&srv_innodb_monitor_mutex); } /********************************************************************** Sprintfs to a buffer the output of the InnoDB Monitor. */ void srv_sprintf_innodb_monitor( /*=======================*/ char* buf, /* in/out: buffer which must be at least 4 kB */ ulint len) /* in: length of the buffer */ { char* buf_end = buf + len - 2000; double time_elapsed; time_t current_time; mutex_enter(&srv_innodb_monitor_mutex); current_time = time(NULL); /* We add 0.001 seconds to time_elapsed to prevent division by zero if two users happen to call SHOW INNODB STATUS at the same time */ time_elapsed = difftime(current_time, srv_last_monitor_time) + 0.001; srv_last_monitor_time = time(NULL); ut_a(len >= 4096); buf += sprintf(buf, "\n=====================================\n"); ut_sprintf_timestamp(buf); buf = buf + strlen(buf); ut_a(buf < buf_end + 1500); buf += sprintf(buf, " INNODB MONITOR OUTPUT\n" "=====================================\n"); buf += sprintf(buf, "Per second averages calculated from the last %lu seconds\n", (ulint)time_elapsed); buf += sprintf(buf, "----------\n" "SEMAPHORES\n" "----------\n"); sync_print(buf, buf_end); buf = buf + strlen(buf); ut_a(buf < buf_end + 1500); if (*dict_foreign_err_buf != '\0') { buf += sprintf(buf, "------------------------\n" "LATEST FOREIGN KEY ERROR\n" "------------------------\n"); if (buf_end - buf > 6000) { buf+= sprintf(buf, "%.4000s", dict_foreign_err_buf); } } ut_a(buf < buf_end + 1500); lock_print_info(buf, buf_end); buf = buf + strlen(buf); buf += sprintf(buf, "--------\n" "FILE I/O\n" "--------\n"); os_aio_print(buf, buf_end); buf = buf + strlen(buf); ut_a(buf < buf_end + 1500); buf += sprintf(buf, "-------------------------------------\n" "INSERT BUFFER AND ADAPTIVE HASH INDEX\n" "-------------------------------------\n"); ibuf_print(buf, buf_end); buf = buf + strlen(buf); ut_a(buf < buf_end + 1500); ha_print_info(buf, buf_end, btr_search_sys->hash_index); buf = buf + strlen(buf); ut_a(buf < buf_end + 1500); buf += sprintf(buf, "%.2f hash searches/s, %.2f non-hash searches/s\n", (btr_cur_n_sea - btr_cur_n_sea_old) / time_elapsed, (btr_cur_n_non_sea - btr_cur_n_non_sea_old) / time_elapsed); btr_cur_n_sea_old = btr_cur_n_sea; btr_cur_n_non_sea_old = btr_cur_n_non_sea; buf += sprintf(buf,"---\n" "LOG\n" "---\n"); log_print(buf, buf_end); buf = buf + strlen(buf); ut_a(buf < buf_end + 1500); buf += sprintf(buf, "----------------------\n" "BUFFER POOL AND MEMORY\n" "----------------------\n"); buf += sprintf(buf, "Total memory allocated %lu; in additional pool allocated %lu\n", ut_total_allocated_memory, mem_pool_get_reserved(mem_comm_pool)); buf_print_io(buf, buf_end); buf = buf + strlen(buf); ut_a(buf < buf_end + 1500); buf += sprintf(buf, "--------------\n" "ROW OPERATIONS\n" "--------------\n"); buf += sprintf(buf, "%ld queries inside InnoDB, %ld queries in queue\n", srv_conc_n_threads, srv_conc_n_waiting_threads); #ifdef UNIV_LINUX buf += sprintf(buf, "Main thread process no %lu, state: %s\n", srv_main_thread_process_no, srv_main_thread_op_info); #else buf += sprintf(buf, "Main thread id %lu, state: %s\n", srv_main_thread_id, srv_main_thread_op_info); #endif buf += sprintf(buf, "Number of rows inserted %lu, updated %lu, deleted %lu, read %lu\n", srv_n_rows_inserted, srv_n_rows_updated, srv_n_rows_deleted, srv_n_rows_read); buf += sprintf(buf, "%.2f inserts/s, %.2f updates/s, %.2f deletes/s, %.2f reads/s\n", (srv_n_rows_inserted - srv_n_rows_inserted_old) / time_elapsed, (srv_n_rows_updated - srv_n_rows_updated_old) / time_elapsed, (srv_n_rows_deleted - srv_n_rows_deleted_old) / time_elapsed, (srv_n_rows_read - srv_n_rows_read_old) / time_elapsed); srv_n_rows_inserted_old = srv_n_rows_inserted; srv_n_rows_updated_old = srv_n_rows_updated; srv_n_rows_deleted_old = srv_n_rows_deleted; srv_n_rows_read_old = srv_n_rows_read; buf += sprintf(buf, "----------------------------\n" "END OF INNODB MONITOR OUTPUT\n" "============================\n"); ut_a(buf < buf_end + 1900); mutex_exit(&srv_innodb_monitor_mutex); } /************************************************************************* A thread which wakes up threads whose lock wait may have lasted too long. This also prints the info output by various InnoDB monitors. */ #ifndef __WIN__ void* #else ulint #endif srv_lock_timeout_and_monitor_thread( /*================================*/ /* out: a dummy parameter */ void* arg) /* in: a dummy parameter required by os_thread_create */ { srv_slot_t* slot; double time_elapsed; time_t current_time; time_t last_table_monitor_time; time_t last_monitor_time; ibool some_waits; double wait_time; char* buf; ulint i; UT_NOT_USED(arg); srv_last_monitor_time = time(NULL); last_table_monitor_time = time(NULL); last_monitor_time = time(NULL); loop: srv_lock_timeout_and_monitor_active = TRUE; /* When someone is waiting for a lock, we wake up every second and check if a timeout has passed for a lock wait */ os_thread_sleep(1000000); /* In case mutex_exit is not a memory barrier, it is theoretically possible some threads are left waiting though the semaphore is already released. Wake up those threads: */ sync_arr_wake_threads_if_sema_free(); current_time = time(NULL); time_elapsed = difftime(current_time, last_monitor_time); if (time_elapsed > 15) { last_monitor_time = time(NULL); if (srv_print_innodb_monitor) { buf = mem_alloc(100000); srv_sprintf_innodb_monitor(buf, 90000); ut_a(strlen(buf) < 99000); printf("%s", buf); mem_free(buf); } if (srv_print_innodb_tablespace_monitor && difftime(current_time, last_table_monitor_time) > 60) { last_table_monitor_time = time(NULL); printf("================================================\n"); ut_print_timestamp(stdout); printf(" INNODB TABLESPACE MONITOR OUTPUT\n" "================================================\n"); fsp_print(0); fprintf(stderr, "Validating tablespace\n"); fsp_validate(0); fprintf(stderr, "Validation ok\n"); printf("---------------------------------------\n" "END OF INNODB TABLESPACE MONITOR OUTPUT\n" "=======================================\n"); } if (srv_print_innodb_table_monitor && difftime(current_time, last_table_monitor_time) > 60) { last_table_monitor_time = time(NULL); printf("===========================================\n"); ut_print_timestamp(stdout); printf(" INNODB TABLE MONITOR OUTPUT\n" "===========================================\n"); dict_print(); printf("-----------------------------------\n" "END OF INNODB TABLE MONITOR OUTPUT\n" "==================================\n"); } } mutex_enter(&kernel_mutex); some_waits = FALSE; /* Check of all slots if a thread is waiting there, and if it has exceeded the time limit */ for (i = 0; i < OS_THREAD_MAX_N; i++) { slot = srv_mysql_table + i; if (slot->in_use) { some_waits = TRUE; wait_time = ut_difftime(ut_time(), slot->suspend_time); if (srv_lock_wait_timeout < 100000000 && (wait_time > (double) srv_lock_wait_timeout || wait_time < 0)) { /* Timeout exceeded or a wrap-around in system time counter: cancel the lock request queued by the transaction and release possible other transactions waiting behind; it is possible that the lock has already been granted: in that case do nothing */ if (thr_get_trx(slot->thr)->wait_lock) { lock_cancel_waiting_and_release( thr_get_trx(slot->thr)->wait_lock); } } } } os_event_reset(srv_lock_timeout_thread_event); mutex_exit(&kernel_mutex); if (srv_shutdown_state >= SRV_SHUTDOWN_CLEANUP) { goto exit_func; } if (some_waits || srv_print_innodb_monitor || srv_print_innodb_lock_monitor || srv_print_innodb_tablespace_monitor || srv_print_innodb_table_monitor) { goto loop; } /* No one was waiting for a lock and no monitor was active: suspend this thread */ srv_lock_timeout_and_monitor_active = FALSE; os_event_wait(srv_lock_timeout_thread_event); goto loop; exit_func: srv_lock_timeout_and_monitor_active = FALSE; #ifndef __WIN__ return(NULL); #else return(0); #endif } /************************************************************************* A thread which prints warnings about semaphore waits which have lasted too long. These can be used to track bugs which cause hangs. */ #ifndef __WIN__ void* #else ulint #endif srv_error_monitor_thread( /*=====================*/ /* out: a dummy parameter */ void* arg) /* in: a dummy parameter required by os_thread_create */ { ulint cnt = 0; UT_NOT_USED(arg); loop: srv_error_monitor_active = TRUE; cnt++; os_thread_sleep(2000000); if (difftime(time(NULL), srv_last_monitor_time) > 60) { /* We referesh InnoDB Monitor values so that averages are printed from at most 60 last seconds */ srv_refresh_innodb_monitor_stats(); } /* mem_print_new_info(); if (cnt % 10 == 0) { mem_print_info(); } */ sync_array_print_long_waits(); /* Flush stdout and stderr so that a database user gets their output to possible MySQL error file */ fflush(stderr); fflush(stdout); if (srv_shutdown_state < SRV_SHUTDOWN_LAST_PHASE) { goto loop; } srv_error_monitor_active = FALSE; #ifndef __WIN__ return(NULL); #else return(0); #endif } /*********************************************************************** Tells the InnoDB server that there has been activity in the database and wakes up the master thread if it is suspended (not sleeping). Used in the MySQL interface. Note that there is a small chance that the master thread stays suspended (we do not protect our operation with the kernel mutex, for performace reasons). */ void srv_active_wake_master_thread(void) /*===============================*/ { srv_activity_count++; if (srv_n_threads_active[SRV_MASTER] == 0) { mutex_enter(&kernel_mutex); srv_release_threads(SRV_MASTER, 1); mutex_exit(&kernel_mutex); } } /*********************************************************************** Wakes up the master thread if it is suspended or being suspended. */ void srv_wake_master_thread(void) /*========================*/ { srv_activity_count++; mutex_enter(&kernel_mutex); srv_release_threads(SRV_MASTER, 1); mutex_exit(&kernel_mutex); } /************************************************************************* The master thread controlling the server. */ #ifndef __WIN__ void* #else ulint #endif srv_master_thread( /*==============*/ /* out: a dummy parameter */ void* arg) /* in: a dummy parameter required by os_thread_create */ { os_event_t event; time_t last_flush_time; time_t current_time; ulint old_activity_count; ulint n_pages_purged; ulint n_bytes_merged; ulint n_pages_flushed; ulint n_bytes_archived; ulint n_tables_to_drop; ulint n_ios; ulint n_ios_old; ulint n_ios_very_old; ulint n_pend_ios; ulint i; UT_NOT_USED(arg); srv_main_thread_process_no = os_proc_get_number(); srv_main_thread_id = os_thread_pf(os_thread_get_curr_id()); srv_table_reserve_slot(SRV_MASTER); mutex_enter(&kernel_mutex); srv_n_threads_active[SRV_MASTER]++; mutex_exit(&kernel_mutex); os_event_set(srv_sys->operational); loop: srv_main_thread_op_info = (char*) "reserving kernel mutex"; n_ios_very_old = log_sys->n_log_ios + buf_pool->n_pages_read + buf_pool->n_pages_written; mutex_enter(&kernel_mutex); old_activity_count = srv_activity_count; mutex_exit(&kernel_mutex); for (i = 0; i < 10; i++) { n_ios_old = log_sys->n_log_ios + buf_pool->n_pages_read + buf_pool->n_pages_written; srv_main_thread_op_info = (char*)"sleeping"; os_thread_sleep(1000000); /* ALTER TABLE in MySQL requires on Unix that the table handler can drop tables lazily after there no longer are SELECT queries to them. */ srv_main_thread_op_info = (char*)"doing background drop tables"; row_drop_tables_for_mysql_in_background(); srv_main_thread_op_info = (char*)""; if (srv_force_recovery >= SRV_FORCE_NO_BACKGROUND) { goto suspend_thread; } /* We flush the log once in a second even if no commit is issued or the we have specified in my.cnf no flush at transaction commit */ srv_main_thread_op_info = (char*)"flushing log"; log_flush_up_to(ut_dulint_max, LOG_WAIT_ONE_GROUP); log_flush_to_disk(); /* If there were less than 10 i/os during the one second sleep, we assume that there is free disk i/o capacity available, and it makes sense to do an insert buffer merge. */ n_pend_ios = buf_get_n_pending_ios() + log_sys->n_pending_writes; n_ios = log_sys->n_log_ios + buf_pool->n_pages_read + buf_pool->n_pages_written; if (n_pend_ios < 3 && (n_ios - n_ios_old < 10)) { srv_main_thread_op_info = (char*)"doing insert buffer merge"; ibuf_contract_for_n_pages(TRUE, 5); srv_main_thread_op_info = (char*)"flushing log"; log_flush_up_to(ut_dulint_max, LOG_WAIT_ONE_GROUP); log_flush_to_disk(); } if (srv_fast_shutdown && srv_shutdown_state > 0) { goto background_loop; } if (srv_activity_count == old_activity_count) { if (srv_print_thread_releases) { printf("Master thread wakes up!\n"); } goto background_loop; } } if (srv_print_thread_releases) { printf("Master thread wakes up!\n"); } #ifdef MEM_PERIODIC_CHECK /* Check magic numbers of every allocated mem block once in 10 seconds */ mem_validate_all_blocks(); #endif /* If there were less than 200 i/os during the 10 second period, we assume that there is free disk i/o capacity available, and it makes sense to do a buffer pool flush. */ n_pend_ios = buf_get_n_pending_ios() + log_sys->n_pending_writes; n_ios = log_sys->n_log_ios + buf_pool->n_pages_read + buf_pool->n_pages_written; if (n_pend_ios < 3 && (n_ios - n_ios_very_old < 200)) { srv_main_thread_op_info = (char*) "flushing buffer pool pages"; buf_flush_batch(BUF_FLUSH_LIST, 100, ut_dulint_max); srv_main_thread_op_info = (char*) "flushing log"; log_flush_up_to(ut_dulint_max, LOG_WAIT_ONE_GROUP); log_flush_to_disk(); } /* We run a batch of insert buffer merge every 10 seconds, even if the server were active */ srv_main_thread_op_info = (char*)"doing insert buffer merge"; ibuf_contract_for_n_pages(TRUE, 5); srv_main_thread_op_info = (char*)"flushing log"; log_flush_up_to(ut_dulint_max, LOG_WAIT_ONE_GROUP); log_flush_to_disk(); /* We run a full purge every 10 seconds, even if the server were active */ n_pages_purged = 1; last_flush_time = time(NULL); while (n_pages_purged) { if (srv_fast_shutdown && srv_shutdown_state > 0) { goto background_loop; } srv_main_thread_op_info = (char*)"purging"; n_pages_purged = trx_purge(); current_time = time(NULL); if (difftime(current_time, last_flush_time) > 1) { srv_main_thread_op_info = (char*) "flushing log"; log_flush_up_to(ut_dulint_max, LOG_WAIT_ONE_GROUP); log_flush_to_disk(); last_flush_time = current_time; } } background_loop: /* In this loop we run background operations when the server is quiet and we also come here about once in 10 seconds */ srv_main_thread_op_info = (char*)"doing background drop tables"; n_tables_to_drop = row_drop_tables_for_mysql_in_background(); srv_main_thread_op_info = (char*)""; srv_main_thread_op_info = (char*)"flushing buffer pool pages"; /* Flush a few oldest pages to make the checkpoint younger */ if (srv_fast_shutdown && srv_shutdown_state > 0) { n_pages_flushed = buf_flush_batch(BUF_FLUSH_LIST, 100, ut_dulint_max); } else { n_pages_flushed = buf_flush_batch(BUF_FLUSH_LIST, 10, ut_dulint_max); } srv_main_thread_op_info = (char*)"making checkpoint"; /* Make a new checkpoint about once in 10 seconds */ log_checkpoint(TRUE, FALSE); srv_main_thread_op_info = (char*)"reserving kernel mutex"; mutex_enter(&kernel_mutex); if (srv_activity_count != old_activity_count) { mutex_exit(&kernel_mutex); goto loop; } old_activity_count = srv_activity_count; mutex_exit(&kernel_mutex); /* The server has been quiet for a while: start running background operations */ srv_main_thread_op_info = (char*)"purging"; if (srv_fast_shutdown && srv_shutdown_state > 0) { n_pages_purged = 0; } else { n_pages_purged = trx_purge(); } srv_main_thread_op_info = (char*)"reserving kernel mutex"; mutex_enter(&kernel_mutex); if (srv_activity_count != old_activity_count) { mutex_exit(&kernel_mutex); goto loop; } mutex_exit(&kernel_mutex); srv_main_thread_op_info = (char*)"doing insert buffer merge"; if (srv_fast_shutdown && srv_shutdown_state > 0) { n_bytes_merged = 0; } else { n_bytes_merged = ibuf_contract_for_n_pages(TRUE, 20); } srv_main_thread_op_info = (char*)"reserving kernel mutex"; mutex_enter(&kernel_mutex); if (srv_activity_count != old_activity_count) { mutex_exit(&kernel_mutex); goto loop; } mutex_exit(&kernel_mutex); srv_main_thread_op_info = (char*)"flushing buffer pool pages"; n_pages_flushed = buf_flush_batch(BUF_FLUSH_LIST, 100, ut_dulint_max); srv_main_thread_op_info = (char*)"reserving kernel mutex"; mutex_enter(&kernel_mutex); if (srv_activity_count != old_activity_count) { mutex_exit(&kernel_mutex); goto loop; } mutex_exit(&kernel_mutex); srv_main_thread_op_info = (char*) "waiting for buffer pool flush to end"; buf_flush_wait_batch_end(BUF_FLUSH_LIST); srv_main_thread_op_info = (char*)"making checkpoint"; log_checkpoint(TRUE, FALSE); srv_main_thread_op_info = (char*)"reserving kernel mutex"; mutex_enter(&kernel_mutex); if (srv_activity_count != old_activity_count) { mutex_exit(&kernel_mutex); goto loop; } mutex_exit(&kernel_mutex); srv_main_thread_op_info = (char*)"archiving log (if log archive is on)"; log_archive_do(FALSE, &n_bytes_archived); if (srv_fast_shutdown && srv_shutdown_state > 0) { if (n_tables_to_drop + n_pages_flushed + n_bytes_archived != 0) { goto background_loop; } } else if (n_tables_to_drop + n_pages_purged + n_bytes_merged + n_pages_flushed + n_bytes_archived != 0) { goto background_loop; } /* mem_print_new_info(); */ #ifdef UNIV_SEARCH_PERF_STAT /* btr_search_print_info(); */ #endif /* There is no work for background operations either: suspend master thread to wait for more server activity */ suspend_thread: srv_main_thread_op_info = (char*)"suspending"; mutex_enter(&kernel_mutex); if (row_get_background_drop_list_len_low() > 0) { mutex_exit(&kernel_mutex); goto loop; } event = srv_suspend_thread(); mutex_exit(&kernel_mutex); srv_main_thread_op_info = (char*)"waiting for server activity"; os_event_wait(event); goto loop; #ifndef __WIN__ return(NULL); #else return(0); #endif }