Do I need to be RESIDENT

We currently have RESIDENT set to -1, if I increase BUFFERS above 2M I get the message 07:55:17 Informix Dynamic Server Stopped. 07:56:49 mt_shm_init: can't create resident segment When I change RESIDENT to 0, I can increase the buffers to whatever I want. I know why I'm getting this error, that is not the reason for this posting. What I'm looking for is an informed opinion of why set RESIDENT to -1 in the first place, Is there a real benefit or only a percieved one? Regards Colin Dawson sending to informix-list

What platform are you on? Making memory resident that is not paged out anyway may not make sense. But on Solaris the "RESIDENT -1" setting has a second effect: It creates shared memory with a page size of 4 MB instead of 8k pages (using the SHM_SHARE_MMU flag of shmat()). This speeds up physical to virtual page translation in the cpu and has a performance benefit on large systems. Michael Colin Dawson wrote: > We currently have RESIDENT set to -1, if I increase BUFFERS above 2M I get > the message > > 07:55:17 Informix Dynamic Server Stopped. > 07:56:49 mt_shm_init: can't create resident segment> > When I change RESIDENT to 0, I can increase the buffers to whatever I want. > I know why I'm getting this error, that is not the reason for this posting. > What I'm looking for is an informed opinion of why set RESIDENT to -1 in the > first place, Is there a real benefit or only a percieved one? > > > > > > Regards > > Colin Dawson > > > sending to informix-list