fsflush consistently 1 of top 5 processes

I consistently see fsflush as one of the top five processes running. Why is this? What should I look at for tuning purposes? We are using a Sun SparcCenter 2000E 1 gig memory (between 800k and 300MB free) 40gig disk (18 disks, 6 controllers Raid 5 Striping 30gig set aside in raw Partitions for INFORMIX Database 18gig of this raw partitions are mirrored) 1.9gig swap (about 1.4gig free) One application running. Three instances of INFORMIX 5.06 User connectivity is mostly TCP/IP from PC's running a custom Powerbuilder application. Average around 30 users (present maximum is 70) a third of which may at times be telnet connections running a 4GL application. Idle time varies between 0 and 15%! Swap and Wait time range between 20 and 40% The application is being provided by a third party, so I do not have access to source code. TIA for any assistance. Robert J. Cline II Cline Enterprises, Inc. semper fi INFORMIX DBA <a href="http://web2.airmail.net/rcline19/resume.htm">Personal Resume</a> <a href="http://web2.airmail.net/rcline19/rj.htm">Personal Home Page</a>