RE: Long checkpoint duration

Try checking to see if any user is in a critical section. Checkpoints wait for all sessions to exit a critical section before proceeding. Run: select username,sid,pid,is_incrit from syssessions where is_incrit = 1 against the sysmaster database. HTH, Bill > -----Original Message----- > From: owner-informix-list@iiug.org [SMTP:owner-informix-list@iiug.org] > On Behalf Of Ruediger Maehl > Sent: Thursday, September 15, 2005 5:49 AM > To: informix-list@iiug.org > Subject: Long checkpoint duration > > Hi folks, > > I do have a severe problem with checkpoint durations on > a Windows 2003 Server with Informix 9.40.TC6. > > Well, it does not look like a performance problem, there > are only 5 to 8 users on that database and a script that > checks regularly Informix for current performance > information. > > The system runs fine for days, checkpoint time is 0 secs. > But sometimes (I cannot define that more precisely) the > script hangs when requesting the current DBSpace usage > with this statement (which looks ordinary to me and runs > fine against many other Informix installations on Unix): > > select name, sum(chksize), sum(nfree) > from sysdbspaces, syschunks > where sysdbspaces.dbsnum=syschunks.dbsnum > and is_sbspace = 0 > and is_blobspace = 0 > group by name > order by name;> > "onstat -" then shows a CKPT REQ. > "onstat -u" then shows a 'C' at flag 1 for the corresponding > user thread. > > The checkpoint may take several hundred seconds, even more than 30000. > > Any ideas what is happening? What the problem can be? > > Any, really any hint is highly appreciated! > > R|diger sending to informix-list