Why read stale data from an asynchronous MySQL replica (slave)? Fetch it from a local cache instead! Good for the clusters overall load, good for your applications performance. And, possible with PECL/mysqlnd_ms 1.3, the replication and load balancing plugin for PHP MySQL users.
The idea is simple
Any application using asynchronous MySQL replication must be capable of handling stale results read from a slave (replica) that is lagging behind the master. The quality of service that the application needs from the database cluster is low. If an application explicitly states the minimum service quality it needs, the underlying systems can adopt to it. That’s a cool thing, because the underlying systems don’t need to do more work than necessary. In the case of a PHP MySQL user, the first underlying system is the database driver library, which is mysqlnd.
Tell mysqlnd …
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