rpl_rli_pdb.cc File Reference

#include "sql/rpl_rli_pdb.h"
#include "my_config.h"
#include <string.h>
#include <sys/time.h>
#include <stdio.h>
#include <algorithm>
#include <atomic>
#include <memory>
#include <string>
#include <unordered_map>
#include <utility>
#include "lex_string.h"
#include "m_string.h"
#include "map_helpers.h"
#include "my_bitmap.h"
#include "my_compiler.h"
#include "my_dbug.h"
#include "my_sys.h"
#include "my_systime.h"
#include "my_thread.h"
#include "mysql/components/services/bits/psi_stage_bits.h"
#include "mysql/components/services/log_builtins.h"
#include "mysql/plugin.h"
#include "mysql/psi/mysql_cond.h"
#include "mysql/psi/mysql_file.h"
#include "mysql/psi/mysql_mutex.h"
#include "mysql/thread_type.h"
#include "mysqld_error.h"
#include "scope_guard.h"
#include "sql/binlog.h"
#include "sql/binlog_reader.h"
#include "sql/current_thd.h"
#include "sql/debug_sync.h"
#include "sql/log.h"
#include "sql/mdl.h"
#include "sql/mysqld.h"
#include "sql/psi_memory_key.h"
#include "sql/raii/sentry.h"
#include "sql/rpl_info_handler.h"
#include "sql/rpl_msr.h"
#include "sql/rpl_replica_commit_order_manager.h"
#include "sql/rpl_reporting.h"
#include "sql/sql_error.h"
#include "sql/sql_lex.h"
#include "sql/table.h"
#include "sql/transaction_info.h"
#include "string_with_len.h"
#include "strmake.h"
#include "thr_mutex.h"

Macros
#define	HASH_DYNAMIC_INIT   4

Enumerations
enum	{ LINE_FOR_CHANNEL = 12 }

Functions
bool	handle_slave_worker_stop (Slave_worker *worker, Slave_job_item *job_item)
	This function is called by both coordinator and workers. More...
bool	set_max_updated_index_on_stop (Slave_worker *worker, Slave_job_item *job_item)
	This function is called by both coordinator and workers. More...
static void	free_entry (db_worker_hash_entry *entry)
bool	init_hash_workers (Relay_log_info *rli)
void	destroy_hash_workers (Relay_log_info *rli)
TABLE *	mts_move_temp_table_to_entry (TABLE *table, THD *thd, db_worker_hash_entry *entry)
	Relocating temporary table reference into entry's table list head. More...
TABLE *	mts_move_temp_tables_to_thd (THD *thd, TABLE *temporary_tables)
	Relocation of the list of temporary tables to thd->temporary_tables. More...
static void	move_temp_tables_to_entry (THD *thd, db_worker_hash_entry *entry)
	Relocating references of temporary tables of a database of the entry argument from THD into the entry. More...
Slave_worker *	map_db_to_worker (const char *dbname, Relay_log_info *rli, db_worker_hash_entry **ptr_entry, bool need_temp_tables, Slave_worker *last_worker)
	The function produces a reference to the struct of a Worker that has been or will be engaged to process the dbname -keyed partition (D). More...
Slave_worker *	get_least_occupied_worker (Relay_log_info *rli, Slave_worker_array *ws, Log_event *ev)
	Get the least occupied worker. More...
static bool	may_have_timestamp (Log_event *ev)
static int64	get_last_committed (Log_event *ev)
static int64	get_sequence_number (Log_event *ev)
static db_worker_hash_entry *	find_entry_from_db_map (const char *dbname, Relay_log_info *rli)
bool	append_item_to_jobs (slave_job_item *job_item, Slave_worker *worker, Relay_log_info *rli)
	Coordinator enqueues a job item into a Worker private queue. More...
static void	remove_item_from_jobs (slave_job_item *job_item, Slave_worker *worker, Relay_log_info *rli)
	Remove a job item from the given workers job queue. More...
static struct slave_job_item *	pop_jobs_item (Slave_worker *worker, Slave_job_item *job_item)
	Worker's routine to wait for a new assignment through append_item_to_jobs() More...
void	report_error_to_coordinator (Slave_worker *worker)
	Report a not yet reported error to the coordinator if necessary. More...
int	slave_worker_exec_job_group (Slave_worker *worker, Relay_log_info *rli)
	apply one job group. More...

Variables
ulong	w_rr = 0
uint	mta_debug_concurrent_access = 0
const char *	info_slave_worker_fields []
const ulong	mts_partition_hash_soft_max = 16
const uint	info_slave_worker_table_pk_field_indexes []

Macro Definition Documentation

HASH_DYNAMIC_INIT

#define HASH_DYNAMIC_INIT   4

Enumeration Type Documentation

anonymous enum

anonymous enum

Enumerator
LINE_FOR_CHANNEL

Function Documentation

append_item_to_jobs()

bool append_item_to_jobs	(	slave_job_item *	job_item,
		Slave_worker *	worker,
		Relay_log_info *	rli
	)

Coordinator enqueues a job item into a Worker private queue.

Parameters

job_item	a pointer to struct carrying a reference to an event
worker	a pointer to the assigned Worker struct
rli	a pointer to Relay_log_info of Coordinator

Returns

false Success. true Thread killed or worker stopped while waiting for successful enqueue.

destroy_hash_workers()

void destroy_hash_workers

(

Relay_log_info *

rli

)

find_entry_from_db_map()

static db_worker_hash_entry * find_entry_from_db_map ( const char *  dbname, Relay_log_info *  rli  )

static

free_entry()

static void free_entry ( db_worker_hash_entry *  entry )

static

get_last_committed()

static int64 get_last_committed ( Log_event *  ev )

static

get_least_occupied_worker()

Slave_worker * get_least_occupied_worker	(	Relay_log_info *	rli,
		Slave_worker_array *	ws,
		Log_event *	ev
	)

Get the least occupied worker.

Parameters

rli	pointer to Relay_log_info of Coordinator
ws	dynarray of pointers to Slave_worker
ev	event for which we are searching for a worker

Returns

a pointer to chosen Slave_worker instance

get_sequence_number()

static int64 get_sequence_number ( Log_event *  ev )

static

handle_slave_worker_stop()

bool handle_slave_worker_stop	(	Slave_worker *	worker,
		Slave_job_item *	job_item
	)

This function is called by both coordinator and workers.

Upon receiving the STOP command, the workers will identify a maximum group index already executed (or under execution).

All groups whose index are below or equal to the maximum group index will be applied by the workers before stopping.

The workers with groups above the maximum group index will exit without applying these groups by setting their running status to "STOP_ACCEPTED".

Parameters

worker	a pointer to the waiting Worker struct
job_item	a pointer to struct carrying a reference to an event

Returns

true if STOP command gets accepted otherwise false is returned.

init_hash_workers()

bool init_hash_workers

(

Relay_log_info *

rli

)

map_db_to_worker()

Slave_worker * map_db_to_worker	(	const char *	dbname,
		Relay_log_info *	rli,
		db_worker_hash_entry **	ptr_entry,
		bool	need_temp_tables,
		Slave_worker *	last_worker
	)

The function produces a reference to the struct of a Worker that has been or will be engaged to process the dbname -keyed partition (D).

It checks a local to Coordinator CGAP list first and returns last_assigned_worker when found (todo: assert).

Otherwise, the partition is appended to the current group list:

 CGAP .= D

here .= is concatenate operation, and a possible D's Worker id is searched in Assigned Partition Hash (APH) that collects tuples (P, W_id, U, mutex, cond). In case not found,

 W_d := W_c unless W_c is NULL.

When W_c is NULL it is assigned to a least occupied as defined by get_least_occupied_worker().

 W_d := W_c := W_{least_occupied}

 APH .=  a new (D, W_d, 1)

In a case APH contains W_d == W_c, (assert U >= 1)

 update APH set  U++ where  APH.P = D

The case APH contains a W_d != W_c != NULL assigned to D-partition represents the hashing conflict and is handled as the following:

a. marks the record of APH with a flag requesting to signal in the cond var when ‘U’ the usage counter drops to zero by the other Worker; b. waits for the other Worker to finish tasks on that partition and gets the signal; c. updates the APH record to point to the first Worker (naturally, U := 1), scheduled the event, and goes back into the parallel mode

Parameters

dbname	pointer to c-string containing database name It can be empty string to indicate specific locking to facilitate sequential applying.
rli	pointer to Coordinators relay-log-info instance
ptr_entry	reference to a pointer to the resulted entry in the Assigned Partition Hash where the entry's pointer is stored at return.
need_temp_tables	if false migration of temporary tables not needed
last_worker	caller opts for this Worker, it must be rli->last_assigned_worker if one is determined.

Note

modifies CGAP, APH and unlinks dbname -keyd temporary tables from C's thd->temporary_tables to move them into the entry record.

Returns

the pointer to a Worker struct

may_have_timestamp()

static bool may_have_timestamp ( Log_event *  ev )

static

move_temp_tables_to_entry()

static void move_temp_tables_to_entry ( THD *  thd, db_worker_hash_entry *  entry  )

static

Relocating references of temporary tables of a database of the entry argument from THD into the entry.

Parameters

thd	THD pointer of the source temporary_tables list
entry	a pointer to db_worker_hash_entry record containing database descriptor and temporary_tables list.

mts_move_temp_table_to_entry()

TABLE * mts_move_temp_table_to_entry	(	TABLE *	table,
		THD *	thd,
		db_worker_hash_entry *	entry
	)

Relocating temporary table reference into entry's table list head.

Sources can be the coordinator's and the Worker's thd->temporary_tables.

Parameters

table	TABLE instance pointer
thd	THD instance pointer of the source of relocation
entry	db_worker_hash_entry instance pointer

Note

thd->temporary_tables can become NULL

Returns

the pointer to a table following the unlinked

mts_move_temp_tables_to_thd()

TABLE * mts_move_temp_tables_to_thd	(	THD *	thd,
		TABLE *	temporary_tables
	)

Relocation of the list of temporary tables to thd->temporary_tables.

Parameters

thd	THD instance pointer of the destination
temporary_tables	the source temporary_tables list

Note

destroying references to the source list, if necessary, is left to the caller.

Returns

the post-merge value of thd->temporary_tables.

pop_jobs_item()

static struct slave_job_item * pop_jobs_item ( Slave_worker *  worker, Slave_job_item *  job_item  )

static

Worker's routine to wait for a new assignment through append_item_to_jobs()

Parameters

worker	a pointer to the waiting Worker struct
job_item	a pointer to struct carrying a reference to an event

Returns

NULL failure or a-pointer to an item.

remove_item_from_jobs()

static void remove_item_from_jobs ( slave_job_item *  job_item, Slave_worker *  worker, Relay_log_info *  rli  )

static

Remove a job item from the given workers job queue.

It also updates related status.

param[in] job_item The job item will be removed param[in] worker The worker which job_item belongs to. param[in] rli slave's relay log info object.

report_error_to_coordinator()

void report_error_to_coordinator

(

Slave_worker *

worker

)

Report a not yet reported error to the coordinator if necessary.

All issues detected when applying binary log events are reported using rli->report(), but when an issue is not reported by the log event being applied, there is a workaround at handle_slave_sql() to report the issue also using rli->report() for the STS applier (or the MTS coordinator).

This function implements the workaround for a MTS worker.

Parameters

worker

the worker to be evaluated.

set_max_updated_index_on_stop()

bool set_max_updated_index_on_stop	(	Slave_worker *	worker,
		Slave_job_item *	job_item
	)

This function is called by both coordinator and workers.

Both coordinator and workers contribute to max_updated_index.

Parameters

worker	a pointer to the waiting Worker struct
job_item	a pointer to struct carrying a reference to an event

Returns

true if STOP command gets accepted otherwise false is returned.

slave_worker_exec_job_group()

int slave_worker_exec_job_group	(	Slave_worker *	worker,
		Relay_log_info *	rli
	)

apply one job group.

Note

the function maintains worker's CGEP and modifies APH, updates the current group item in GAQ via slave_worker_ends_group().

param[in] worker the worker which calls it. param[in] rli slave's relay log info object.

return returns 0 if the group of jobs are applied successfully, otherwise returns an error code.

Variable Documentation

info_slave_worker_fields

const char* info_slave_worker_fields[]

Initial value:

= {
    "id",
    
    "group_relay_log_name", "group_relay_log_pos", "group_source_log_name",
    "group_source_log_pos",
 
    
    "checkpoint_relay_log_name", "checkpoint_relay_log_pos",
    "checkpoint_source_log_name", "checkpoint_source_log_pos",
 
    
    "checkpoint_seqno",
    
    "checkpoint_group_size",
    
    "checkpoint_group_bitmap",
    
    "channel_name"}

info_slave_worker_table_pk_field_indexes

const uint info_slave_worker_table_pk_field_indexes[]

Initial value:

= {
    LINE_FOR_CHANNEL,
    0,
}

mta_debug_concurrent_access

uint mta_debug_concurrent_access = 0

mts_partition_hash_soft_max

const ulong mts_partition_hash_soft_max = 16

w_rr

ulong w_rr = 0