I'd like to thank all of the DrupalCamp Ottawa organizers. Everything appeared to run smoothly, and there was a great turnout for the second annual event.
I gave a presentation on Drupal performance to a completely-packed room. Either the subject matter interested a lot of people, or the room was too small. From my perspective, it's difficult to say which, but I'd like to think my topic was something folks wanted to hear.
As great as Drupal 7 core can be, it doesn't scale well for Web sites with a lot of content and/or a lot of users. To make it perform better under these scenarios, it's necessary to make use of several strategies, tools and techniques.
If your site is left for a while, say throughout the night, and you find that hitting it for the first time in the morning (i.e. a cold start, an initial run) takes longer to load than after clearing your caches, then it's fair to assume that it's not merely a problem of caches expiring and refilling.