Contents
How does PT table sync work?
For each table and range of values that shows differences between the master and slave, pt-table-checksum will sync that table, with the appropriate WHERE clause, to its master. This automatically sets –wait to 60 and causes changes to be made on the master instead of the slave.
How do I know if MySQL replicate is in sync?
Check MySQL Replication Status on Query Servers
- Start the MySQL command-line utility on the slave server: # cd /opt/mysql/mysql/bin.
- Check the replication status using the show slave status command (the status of the slave server is conveyed by the Slave_IO_Running and Slave_SQL_Running column values):
How do I use PT Archiver?
If you want to run pt-archiver with a specific index you can use the “-i” option in –source DSN options. The “-i” option tells pt-archiver which index it should scan to archive. This appears in a FORCE INDEX or USE INDEX hint in the SELECT statements that are used to fetch rows to archive.
Which is the primary source in MySQL to improve performance?
A sample of this structure is shown in Figure 16.3, “Using an Additional Replication Source to Improve Performance” . For this to work, you must configure the MySQL instances as follows: Source 1 is the primary source where all changes and updates are written to the database.
How to improve the performance of the replication process?
One way to improve the performance of the replication process is to create a deeper replication structure that enables the source to replicate to only one replica, and for the remaining replicas to connect to this primary replica for their individual replication requirements.
How to split up responsibility for replicating different databases?
To do this, set the relay_log system variable to specify the location of the relay log. If the replicas are significantly slower than the source, you may want to divide up the responsibility for replicating different databases to different replicas. See Section 16.3.5, “Replicating Different Databases to Different Replicas” .
What do the replicas do in source 2?
Replica 1, Replica 2, and Replica 3 act as replicas to Source 2, and replicate the information from Source 2, which actually consists of the upgrades logged on Source 1.