Hello Zahid If you've set threads (-t 1) then Zope should run singlethreaded. The prformance of pages beeng rendered should be unchanged. The problem would be that two or more surfers cannot access the site at the same time. Check the Appendix of http://www.zope.org/Members/glpb/solaris. There is a script & explanation on how to test this behaviour. Regards Oliver Erlewein