Restarts are required for certain, infrequent maintenance activities. Note that there is no loss of service while a single node restarts.

When a data node restarts, it first attempts to load the data into memory from the local log files and then it will catch up with any subsequent changes by retrieveing them from the surviving node(s) in its node group.

 Based on this, you would expect the time taken to restart a data node to be influenced by:

1. The amount of data that was stored on the data node before the restart
2. Rate of updates being made to the data during the restart
3. Network performance (assuming the data is being updated during recovery)

The times will also be influenced bycertain configuration parameters, performance of the host machine and whether the multi-threaded data node (ndbmtd) is being used.

To provide some insight into how these …

There is another live webinar on MySQL Cluster 7.0 scheduled for 27th May 09:00 (Western European time) / 08:00 (UK time) / 11:00 (Eastern European time) and you can register here.

Alternatively, if you can’t wait that long then you can watch/listen to the play-back of the original webinar.

Note that you may need to install the WebEx Player (Windows and Mac) - unfortunately, there doesn’t seem to be a simple, supported solution for LINUX users but you can always download the slides (PDF format) from the same link or else wait until 27th May and view it live.

What’s New in the Next Generation of MySQL Cluster?
Thursday, April 30, 2009

The answer is yes – kind of.

Stored procedures are implemented in a MySQL Server and can be used regardless of the storage engine being used for a specific table. One inference from this is that they won’t work when accessing the Cluster database directly through the NDB API.

This leads to the question of whether or not that limitation actually restricts what you can achieve. This article gives a brief introduction to stored procedures and looks at how the same results can be achieved using the NDB API.

Stored procedures provide a rudimentary way of implementing functionality within the database (rather than in the application code). They are implemented by the database designer and have the ability to perform computations as well as make changes to the data in the database. A typical use of stored procedures would be to control all access to the data by a user or application – for example, to impose extra checks on …