This issue is very common and commonly faced by DBA, developers and server management team on production server i.e. SQL server leads into 100% CPU usage and also start consuming all available memory. Now most of the time you have seen technical people restarting sql services, or killing long running processes and even restarting complete server, and they can avoid this situation. Before starting any thing I would like to discuss a common myth people have that this is happening because of long running queries only. Which is not all ways true, some times:
Longer running query can be problem
Query having maximum worker time are also problem
Query execution count can also cause problem
Now in order to fix this issue you have to go through below video:
