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Search Results for: read write slave

Changing an async slave of a PXC cluster to a new Master

Async and PXC A common question I get about Percona XtraDB Cluster is if you can mix it with asynchronous replication, and the answer is yes!  You can pick any node in your cluster and …


Disconnecting a replication slave is easier with MySQL 5.5+ (RESET SLAVE vs. RESET SLAVE ALL)

It’s not uncommon to promote a server from slave to master. One of the key things to protect your data integrity is to make sure that the promoted slave is permanently disconnected from its old …


Read/Write Splitting with PHP Webinar Questions Followup

Today I gave a presentation on “Read/Write Splitting with PHP” for Percona Webinars.  If you missed it, you can still register to view the recording and my slides. Thanks to everyone who attended, and especially …


Webinar on Read/Write Splitting with PHP

I’ll be presenting a webinar next Wednesday, January 23 at 10 a.m. (Pacific Time), about issues application developers should think about for scaling out read-query traffic using multiple MySQL instances in a replication pair. Specifically, …


How to lag a slave behind to avoid a disaster

MySQL Replication is useful and easy to setup. It is used for very different purposes. For example: split read and writes run data mining or reporting processes on them disaster recovery Is important to mention …


TokuDB v6.0: Getting Rid of Slave Lag

Master/slave replication is an important tool that gets used in many ways: distributing read loads among many slaves for performance, using a slave for backups so the master can handle live load, geographically distributed disaster …


How FLUSH TABLES WITH READ LOCK works with Innodb Tables

Many backup tools including Percona Xtrabackup, MyLVMBackup and others use FLUSH TABLES WITH READ LOCK to temporary make MySQL read only. In many cases the period for which server has to be made read only …


How to know if you’re updating Slave you should not ?

When replication runs out of sync first question you often ask is if someone could be writing to the slave. Of course there is read_only setting which is good to set in the slave but …


How SHOW SLAVE STATUS relates to CHANGE MASTER TO

As you probably know MySQL Replication (statement based) works by fetching statements from MASTERs binary log and executing them on the SLAVE. Since MySQL 4.0 this process is a bit more involved having events passing …


Managing Slave Lag with MySQL Replication

The question I often get is how far MySQL may fall behind and how to keep replication from lagging. The lag you will see will vary a lot from application to the application and from …