We at Tag1 have used the Cacti Memcache templates many times. (http://dealnews.com/developers/cacti/memcached.html) They have become a staple for us and many others. However, we and one of our clients have had issues making them work for monitoring multiple Memcache instances (running on different ports) on the same host. It is possible to make this work with the vanilla templates, but it is a bit difficult.

There are some standard tools in every MySQL DBA's back pocket, these include maatkit, mysqlreport and mysqlsla. I have a new addition to this: statpack (http://www.markleith.co.uk/?p=21)

There are few options for sharing webroots among multiple webnodes. This is especially true for Drupal, which has a files directory that could be constantly diverging on each webnode. Usually people decide to go with NFSv3. This is what we do on drupal.org and most of my clients do at Tag1. Sadly, this is not really a decision on merit, but on a lack of other options. NFSv3 is pretty much like communicating with two cans and a string.

I've had the opportunity in the last few days to use quite a few cool little utilities that made my life considerably easier. I've known about most of them for awhile, but discovered some new tools or new uses for old tools and wanted to share two of them.

I recently joined Tag1 Consulting full time. My main project since I joined was building up our monitoring infrastructure. My personal goal being world domination, but first the best monitoring system I can build. Baby steps...baby steps. For quite awhile now, I've used the monitoring system we built at the Open Source Lab to detect and diagnose problems with drupal.org, apache.org, kerneltrap.org and many more Free Software projects hosted at the lab. These experiences convinced me of the absolute necessity of a robust monitoring system.

The following collection of patches are useful performance and scalability tweaks that can be applied to Drupal websites. This collection will continue to grow, and is being maintained as a reference page for our online performance and scalability book. As new versions of Drupal are released, updated version of these patches will be added to this page.

To learn more about how these patches work, where they came from, and if they've been merged upstream, you can click the readme link following each patch's brief description. We welcome all feedback, and suggestions for other patches that should be included in this collection.

Until recently, I was a student employee at the Oregon State University Open Source Lab. My career there ended, like many, with that painful process known as graduation. I got invaluable experience at the lab, not the least of which being the knowledge gained as their main (only) database administrator. One of my great pleasures in that position, was learning how to configure MySQL replication and manage clusters of replicating database servers. Even the simple case of a single master and a single slave has its edge cases.

I have completed a rough draft of the first chapter of "Drupal Performance and Scalability". The first chapter of this online book is divided into four sections, the first of which focuses on the importance of fully defining your performance and scalability goals, helping you to identify what you need to accomplish and how to set concrete and attainable goals. The second section discusses monitoring and measuring your ongoing progress, helping you decide what you need to monitor, and how to monitor it. The third section stresses the importance of making regular backups, discussing what needs to be backed up, and offering example scripts for backing up your entire website, including the database. Finally, the fourth section takes an in depth look at using revision control tools to manage your website, providing useful recipes showing how Git can track changes to your website, helping you update to new releases and push those updates into production.

It is important to realize that this is a rough draft, and as such it may contain spelling or grammatical errors, it may be missing key points, and the writing style may not be very polished. However, the book has to start somewhere, and this is the first step toward the end goal of publishing a useful and freely available online resource. I welcome all criticisms, suggestions and feedback. If you find errors in the text or have specific comments, you can help with this writing project by posting your feedback on the appropriate page. The current status of this project is tracked here.

In previous search benchmarks, I utilized random content generated with Drupal's devel module. In these latest benchmarks, I used an actual sanitized copy of the Drupal.org community website database, with email addresses and passwords removed. The first tests were intended to confirm that Xapian continues to perform well with large amounts of actual data. Additional tests were performed to measure the effect of various MySQL tunings and configurations. The following data was derived from several hundred benchmarks run on an Amazon AWS instance over the past week using the SearchBench module.

These tests confirm that Xapian continues to offer better search performance than Drupal's core search module. Contrary to popular belief, the data also shows that using the InnoDB storage engine for search tables significantly outperforms using the MyISAM storage engine for search tables, especially when your database server has sufficient RAM. The data also confirms that allocating additional RAM for MySQL's temporary tables can also improve search performance.

Tag1 Consulting is focused on improving Drupal's performance and scalability. We also believe that when information is freely shared, everyone wins. Toward these ends, we are working on an online book titled, "Drupal Performance and Scalability". The book is divided into five main sections, Drupal Performance, Front End Performance, Improved Caching and Searching, Optimizing the Database Layer, and Drupal In The Cloud. The book is primarily aimed toward users running Drupal on the LAMP stack, with chapters applicable to everything from low-end shared hosts to large-scale multi-server installations.

By publishing on-line, we aim to encourage you to participate in the book writing process as an editor and a technical reviewer. You will currently find the book's complete outline online, along with descriptions of each planned section and chapter. As the book evolves, it will continue to be updated online in real time. We encourage you to post comments with suggestions, critical feedback, grammatical corrections, or anything else relevant to our ongoing effort.