Once installed, you can view the Cron table by navigating to System > Cron Doctor, which will then bring up a table of all Cron Jobs> This is where you can view complete Cron schedule of tasks, delete Cron entries (useful when stuck at processing), check execution times and view any errors produced.
Additionally, if Cron jobs are processing for an extended period, an email alert will notify the store owner (or whichever email address is added to the configuration screen) so that the situation can be investigated.
You can set up with notification by navigating to System > Configuration > Advanced > Cron Doctor. It is here that you can determine how and to whom you would like notification to be made should a nominated amount of time pass that a job has been running before reporting it as a zombie.
Once installed and configured, you can find the Cron Doctor Dashboard by navigating to System > Cron Doctor.
Once on the Cron Doctor, you will find a detailed list of all cron jobs and the corresponding time and date that they had been created, scheduled, executed and finished at. Just as you can on another Magento Dashboards, you can also sort by any of detailed criteria so as to isolate the last time a cron job had been executed, whether it ran successfully, or perhaps how long it took to finish.
In the below example, I have searched by the Job Code 'Enterprise Reward Expire Points' which will then bring up a detailed history of all past records of this cron job running.