Hi,

although maybe not the cause of your problem I experienced something similar recently. The reason in my case was that the queue of the computation cluster was full, causing a large backlog of submitted processes - in my case it took almost 24 hours for my submitted jobs to actually start running. You can check the status of your jobs with
If the second last column ('S') says R then your job is running currently. Otherwise you can look for the name of the queue you submitted to in the third column ('Queue') and then enter the following command:
There you should look for the columns 'Que' and 'Run' to get an idea of how many jobs are waiting to be executed. If you don't want to keep running these commands over and over, just add 'watch ' in front to have a continuous report.