Art, thanks for this post. I use Rackspace cloud sites for all of my projects, and overall I really like them as a company.

But I seem to be more and more running into issues where my Drupal sites are getting the occasional:

"Site temporarily unavailable.
Connection timed out - please try again."

Then I refresh once or twice and the page comes up. I've talked to Rackspace and they've tried to be as helpful as they can, but it seems that something in Drupal itself is causing these queries to take so long. It also seems more frequent in the last year or so, and both with Drupal 6 and Drupal 7 sites. This timeout message seems particularly frequent on the modules page.

To your knowledge are there any key offenders as far as commonly-used modules that might be causing this problem?

Thanks,
Chris