Ajax.php eating up memory? Setting up cache?

[6ironmaiden9]

Hi ajax.php is eating up memory on my server and my server people at hostgator (I'm on a vps) Told me to setup a caching mechanism for the forum script. How do i go about this?

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Actually i located it down its the shoutbox script that is hogging resources as soon as i take it down we stop getting internal server errors etc. Its vbshout the latest version. (pro)