mod_overload error in server log?

i am getting a lot of this error in my server log and a lot 500 server errors on the site.

[Fri Nov 23 14:22:13 2012] [notice] mod_overload: Overloaded, 1 minute load average, current load: 71, max load allowed: 64

Can anyone explain what this means and how to resolve it. Thanks
Chris

You possibly have web server issues at the looks of it. mod_overload is a simple module to prevent web server from overloading, by checking load averages. Rarely do you ever see this show up. I would contact your web host about that one. About the 500 errors:
Read: http://forum.opencart.com/viewtopic.php?f=144&t=50555