Here's a quick tip for people running multiple Drupal instances on one server: don't run cron for all sites on the same moment but try to spread it.
Suppose I have 5 sites: site1.tld, site2.tld, ... and I want to run cron each 12 hours. I would enter the following using crontab:
Packt Publishing is on a roll. They have been releasing a few Drupal books recently on a broad variety of topics. We have seen books on Social Networking with Drupal, JavaScript and jQuery, multimedia, ...
Last week they have released a new book focusing on performance and maintenance, called Drupal 6 Performance Tips. Although the title focusses on the performance topic, a lot of tips are also provided for maintaining or developing your site.
I just pulled my hair out looking for what caused this, but eventually found it after scanning the module files. The issue was that overriding hook_theme_blocks wasn't possible in some theme. The version in the theme wouldn't get called at all, even after rebuilding the theme registry by clearing the cache. The culprit was the Block Translation module.
There's quite a few information available on how to install Apache Solr for your Drupal website. One of the best places to start is the Apache Solr Search Integration module documentation page. In this post I will gather all the bits and pieces for installing Solr in Tomcat on one specific platform: Snow Leopard. This is the platform I'm developing Drupal sites on and the great thing is it has all the needed Java stuff built in, so it's quite easy to install Solr and Tomcat. This method might work on some other systems too having Java 1.6 (with mostly some minor adjustments) but I've not tested this.
Search is ubiquitious. It's available on all sites, desktop applications, ... A good search engine is something essential for letting your users get what they want. There's a lot of factors that define what a makes a good search engine: speed, accuracy of the results, ...
Drupal has already a plethora of solutions these problems. There is a search module in core. We also have integration with Google Search Appliance, Custom search, Lucene, ... But most recently Apache Solr is hotter than hot and seems to become the standard replacement for Drupal's core search solution. Even more now since Acquia uses it as the core of one of its flag products, Acquia Search.