MySQL master-Slave synchronization delay

[Email protected] (none) 02:48:05>show slave status\g;
1. Row ***************************
Slave_io_state:waiting for Master to send event
master_host:192.168.15.11
Master_user:dbsync
master_port:3306
Connect_retry:60
master_log_file:mysql-bin.002351
read_master_log_pos:276113513
relay_log_file:relaylog.007789
relay_log_pos:178335825
relay_master_log_file:mysql-bin.002339
Slave_io_running:yes
Slave_sql_running:yes
replicate_do_db:
replicate_ignore_db:
Replicate_do_table:
Replicate_ignore_table:
Replicate_wild_do_table:
Replicate_wild_ignore_table:
last_errno:0
Last_error:
skip_counter:0
exec_master_log_pos:178335662
relay_log_space:13178574309
Until_condition:none
Until_log_file:
until_log_pos:0
Master_ssl_allowed:no
Master_ssl_ca_file:
Master_ssl_ca_path:
Master_ssl_cert:
Master_ssl_cipher:
Master_ssl_key:
seconds_behind_master:0

Restart from the library, master-slave synchronization is normal.

Because the read-only synchronization from the library to the main library takes single-threaded synchronization, and the pressure of the main library is concurrent multithreaded writes, this can result in a data delay solution from the library: open read-only from the library of parallel replication is the fundamental way to solve this problem, want to completely solve the business write pressure is normal, Proper optimization or splitting of the business ensures that TPs in the main library does not cause slave delays. Expansion: In MySQL5.6, concurrent replication is introduced, which is the database level, which means that one SQL thread can process a continuous transaction of a database without waiting for other databases to complete. This version of concurrent replication can be understood as a database of one SQL thread. The parameters associated with concurrency are as follows: Slave_parallel_workers//number of worker threads Slave-checkpoint-group//How many transactions to make once Checkpointslave-c Heckpoint-period//How often do you do a checkpointslave-pending-jobs-size-max//, the maximum size of an event that is sent to a worker, in the waiting state

MySQL master-Slave synchronization delay