DrupalCon is the twice-yearly gathering of Drupalistas to learn about, discuss, and contribute to Drupal, networking with other Drupal community members in the process.

Here is the video of Rasmus Lerdorf, the creator of PHP discussing certain performance-related topics with a focus on Drupal.

This particular video shows all the coverage from the first day of Drupal Copenhagon, including an interview with Dries Buytart himself.