Tungsten clusters use the Tungsten Connector to ensure your applications transparently connect to the master. This enables failover and seamless switching of masters for maintenance. However, you can do far more. Tungsten Connector allows you to make better use of hardware by load balancing SQL traffic to slaves. There is also a wealth of configuration settings to help Tungsten Connector manage

It is time for christmas presents: some sharding support and cache locality optimizations are coming with PECL/mysqlnd_ms 1.5. PECL/mysqlnd_ms is a plugin for the mysqlnd library. The plugin adds replication and load balancing support to any PHP MySQL API (mysql, mysqli, PDO_MySQL) if compiled to use the mysqlnd library.

As a MySQL user you can choose between a wide variety of clustering solutions to scale-out. Your options range from eventual consistent solutions to strong consistent ones, from built-in (MySQL Replication, MySQL Cluster) to third party or home-grown. PECL/mysqlnd_ms is a client side load balancer that aims to serve all. …

Here's a neat tip posted by Henrik Ingo from the MySQL Telecom Team

It's not really properly documented in the manual part, but I found in the changelogs, and confirmed on IRC that to do load-balancing across the SQL nodes in MySQL Cluster, you would use a different JDBC connection string with the "loadbalance" keyword added...

jdbc:mysql:loadbalance://host-1,host-2,...host-n/database?loadBalanceBlacklistTimeout=5000

mysql-proxy defaults to round-robin load balancing. There are fancy tricks around to get mysql-proxy to balance connections based on how many idle connections there are in a proxy-based connection pool.

But there is no code that I found that would simply load balance based on “always go to one server, go to another server only when the first server is down.”

Well, I spent way too long figuring this out today, again running into the problem where the manual hasn’t been updated. I have indeed made a Forge snippet of this code, but it does not hurt to post it here.

This was in fact taken from …

Whew! I just finished a marathon of revisions. It's been a while since I posted about our progress, so here's an update for the curious readers.

Continuing in the tradition, which I hope has been as helpful to you as it has been to me, I'm opening the floor for suggestions on chapter 9 of the upcoming High Performance MySQL, Second Edition. Unlike the other chapters for which I've listed outlines, this one isn't substantially written yet. It's in detailed outline form at this point (a tactic that has worked very well for us so far -- I'll write about that someday).

I'm trying to get feedback much earlier in this chapter's lifecycle, for several reasons. Two of the most important are that this is one of the first chapters I've had a chance to really take from scratch, and the chapters I haven't written from scratch have been harder to organize, as you've probably seen from the last few outlines I posted. There's a lot of value in working top-down on this deep encyclopedia-style material.

Read on for the outline and more thoughts I just can't keep to myself.