I have a VPS which hosts a site (http://www.tanguay.info/web) which gets about 1800 unique visitors per day.
The site ran fine getting 3-second response times for weeks.
All of a sudden on Friday at 4PM the site became inaccessible with response times at 30+ seconds and has been down ever since. Here is the pingdom graph:
Even after rebooting it numerous times, I cannot get response times back below 30 seconds. With the "top" command I see that there are 30+ Apache processes running which seem to be taking up over 90% of the memory.
What could be causing this? Why would there be so many Apache processes open, especially since the site is basically inaccessible now anyway? Could it be that these processes are simply not getting closed somehow?