Is Drupal 7 slower than Drupal 6?

Question

One of the problems with Drupal in general is that it is slow. We run Pressflow 6 in a high traffic production environment and it consumes a lot of resources for a site of its size.

Much has been made of whether Drupal 7 is slower than Drupal 6: http://drupal.org/node/615822

It appears that this is indeed the case, but can anybody confirm?

Many thanks, Chris.

Answer 1

Yes. I can confirm. However.

First the bad news:

• Drupal7 core is more complex. Complexity costs performance.
• Drupal7 core is bigger: more features, more in core. more equals slower.

Then the theory:

• In Drupal6, approx. 95% of the projects included CCK. Call that Drupal+. Drupal7 comes with CCK out of the box. Drupal6+ is slower then Drupal7.
• Drupal7 offers a lot of enterpris-ish abilities for performance tuning. Memcached, (Varnished)Proxy support, Database balancing (master/slave etc). Something that Drupal6 could not do.

However, Drupal6 pressflow had these enterprise-ish things build in (in fact: these pressflow features made it into core, offering the basis for Drupal7).

Drupal7 is slower then Pressflow Drupal6. Drupal7 offers performance features that Drupal6 did not offer, but that PressflowDrupal6 did offer.

Many projects also have views module enabled. Views3 in Drupal7 offer a lot of performance improvements (enterprise-ish features) over Views2 for Drupal6.

My advice: untill there is a performance-optimised Drupal7 (Pressflow Drupal7, for example) Just stay with your Pressflow Drupal 6. It is in both theory and practice a lot faster. If you can benefit from the Views3 improvements and features, then go for Drupal7+views3, that will give you more options to tune performanceissues.