Usually, we never spontaneously shut down sites. We are fairly liberal when it comes to server usage as long as no one abuses it.
If we find a script you are running is draining more than your fair share of the server's resources we will give you a warning and ask that you discontinue using it, or trim it down. If you are looking to run resource intensive scripts we suggest a dedicated server.
Since you are on shared hosting environment other customers sites will be affected.