JacksonRiver/springboard_modules — pull request #147 by pcave (2012-09-28 15:34:10+00:00)
Title: T465 - Add exclusive lock to the queue processor routine.

This change will prevent multiple processes from running the
standalone queue processor cron routine simultaneously. It uses
the Drupal function lock_aquire() to prevent race conditions
during processing of the queue.

The existing locking system was not strong enough to prevent these
race conditions, therefore items could end up in multiple batches
during a single cron run. This leads to an almost endless cycle of
retries when an item that has already been created tries to be
created again and again.