I have try Cyrus IMAP 2.0.13 before i use Cyrus IMAP 1.6.22 (on solaris 2.6). We use only imap and pop with 20,000 users. I have put this in my cyrus.conf imap cmd="imapd" listen="imap" prefork=2 maxchild=30 pop3 cmd="pop3d" listen="pop3" prefork=2 But i don't understand how work the master process. When an imapd ( or pop) process stop ( on timeout )? Can we configure the maximum number of connection for on process ? I was suprised when I saw the the size of one imapd process. If I use the ps command, i saw that each process's size is 22Mo. Why does they so large ? Thank to give me informations. Server : Solaris 2.6 SUN Ultra Entreprise 450 1 Go Of RAM Hard Drive : 2*4,2 Go 3*9,1 Go 1*18 Go -- Julien Marchal -- Email : [EMAIL PROTECTED] Université NANCY 2 - C.R.I. 13, Rue Michel Ney CO 75 - 54037 Nancy Cédex