typo3 extremly slow what could be a reason
<p>I've go a ubuntu 14.04lts vserver with 2 vcores and 4GB ram (only 200MB used)</p>

<p>on this server are running 4 typo3 instances but all are test installations so they don't have lots of visits.</p>

<p>my problem is that they are very very slow.</p>

<p>cpu usage 2%
ram usage 200MB</p>

<p>what could be a reason for a slow typo3 in frontend as well as in backend.</p>

<p>its typo3 7.6.4</p>

<p>thanks</p>