Upgrading from Drupal to Pressflow

I have drupal based website (Drupal version is 6.19), it is very heavy content website (about 400K articles in it).

By following Rule one of using Drupal, I didnt make any change on the core. but i have a lot of enabled modules and some of them were customized.

Now, I am suffering of the performace and I need to enhance it. I never us开发者_开发技巧ed Pressflow before, but I have read some articles saying that pressflow is better than Drupal. is it safe to upgrade from Drupal to Pressflow? and if so, how to do it?

Thanks for your help

Pressflow adds the following features to Drupal.

• Support for database replication
• Support for Squid and Varnish reverse proxy caching
• Optimization for MySQL
• Optimization for PHP 5

Pressflow is a 100% api-compliant replacement for your standard Drupal Core. There are no database schema changes. So long as you are running a normal Drupal core and meet the other system requirements (PHP5.x, MySQL 5.x), Pressflow is a "drop in" replacement.

Short answer: probably not. Especially since you state that you "have a lot of enabled modules and some of them were customized."

Longer answer: Pressflow's changes are relatively small, and hardly break the APIs. However, there are some incompatibilities, most in the area of database-access and caching. Especially modules that knowingly or unknowingly don't play by Drupals coding guidelines, will probably break. My suggestion: just try, if a module breaks: fix it (and file a patch).

But the real question is: are you going to benefit from Pressflow? It is not simply "better". It allows database-replication, such as load-balancing or master-slaves. Do you intend to use that? It introduces better support for caching proxies. Are you planning to run a squid or some other caching proxy? It has some small changes in, for example, the area of caching, that may (but may not) help you; depending on your current usage.

My suggestion: first see how to improve performance without Pressflow. Then, once you come across an area where Drupal is of little help, but which is "fixed" in Pressflow, consider changing.

Few modules have issues with Pressflow and if they do, someone else probably found them. Try searching if any of you modules is incompatible.

Its actually slowed out websites down. This is due to too many modules setup and no caching of our blocks. I am working through things now trying to setup caching and memcache. The issue I have though is that our editors want to see changes now. So some of this might be training. The other issue I have is that we have the fimage module setup and it does not work with the minimum cache lifetime setting so we do not get that benifit at all. In theory it should speed up your site but just let it be known it might do the opposite.