Hi Jens I knew of the 7 thread limit of the DB connections but I wanted to make sure. The tests are nearly finished and I have bad news. As it appears the values for -t and -i are extremely dependant on the type of hardware used and the type of coding (mainly static or manny loops,.-..). E.g. I have noticed, that when using 20 concurrent users the max time for an answer was generally lower when using -t 3 than when using -t 7 (2%-28% faster)! This was a totally unexpected result. As I said before this seems to be a really individual thing. This means that I have to do the same tests on my production system (taking it down for that time), which means LONG nights :-( Now I'm going to test the effect of the Object Cache and -if time allows- the RAM & other caches of Zope. I hope that the performance curve there is a little more predictable.... ;-) regards Oliver Erlewein