Avoiding Deadlocks in Galera – Setting Up HAProxy for Single-Node Writes and Multi-Node Reads
Galera cluster has known limitations, one of them is that it uses cluster-wide optimistic locking. This may cause some transactions to rollback. With an increasing number of writeable masters, the transaction rollback rate may increase, especially...
NoSQL Battle of the East Coast – Benchmarking MongoDB vs TokuMX Cluster
In this post we will compare performance of MongoDB and TokuMX, a MongoDB performance engine from Tokutek. We will conduct three simple experiments that (almost) anyone without any programming skills can try and reproduce. In...
Scaling WordPress and MySQL on Multiple Servers for Performance
Over the years, WordPress has evolved from a simple blogging platform to a CMS. Over seven million sites use it today, including the likes of CNN, Forbes, The New York Times and eBay. So, how...
Turning a MongoDB Replica Set into a Sharded Cluster
Replica Sets or Sharded Clusters? ** Diagrams updated on May 22nd. Thanks to Leif Walsh from Tokutek for his feedback. Replica Sets are a great way to replicate MongoDB data across multiple servers and have...
Using HAProxy with Your Database Cluster
Severalnines s9s_haproxy script allows you to install HAProxy and loadbalance over the MySQL servers in your cluster. To learn more about HAProxy and SQL load balancing, see this HAProxy Tutorial. By defauly s9s_haproxy installs HAProxy...
Scaling Drupal on Multiple Servers with Galera Cluster for MySQL
This post shows you how to move from a single instance Drupal/MySQL to a multi-server environment. A well designed multi-server deployment not only allows Drupal to scale, but will also enhance redundancy by removing single...