drush features-revert-all is very slow on a site with many feature modules. A quick look in the command callback function reveals that drush_invoke_process() is called for each feature, which means that Drupal is bootstrapped once for every feature module on the site. This is should be an easy win, but there might be other performance gains to be had.
PASSED: [[SimpleTest]]: [MySQL] 36 pass(es). View