I'm having a problem with shitty programmed site reload apps for iphone causing big bandwidth issue, I don't know the name of the app, but it's resulting in 100K reloads from one user a day.
If it's just that one app, you could ban its user agent (if it's unique). If you're looking for a more general solution instead, take a look at mod_evasive and/or mod_throttle (edit: actually, make that mod_cband...? Haven't used Apache for some time) for Apache.
Post a few lines of the log with the GET info in it, blank out the ip, i can probably get you sorted out. Which apache ver are you using? Edit: This smells more like ddos than a 'normal' app btw.
Really sorry for the delay guys having some offline issues. (Re: PM @retro) I'm not sure what could be causing this but it sounds like a bot or some infected app. If you could PM me with some logs I'll take a look later tonight. Worst case you could always block the ip's used. EDIT: @assembler_EX was thinking about this while waiting for my taxi. It could be a DOS/DDoS. Are you by chance running Apache 2.x? There's one type of attack that sends multiple requests to an Apache server which in turns overloads it to the point it would become unresponsive. (Won't name it just incase your server is vulnerable to this attack.)