How to run Solaris 2.3 with little or no swap
My understanding is that Solaris 2.3's virtual memory equals
real memory plus swap. Is it possible to run Solaris 2.3 with
little or no swap? If it is, does anything special, other than
plenty of real memory, have to be done?
Many thanks to the following who replied:
steve@cegelecproj.co.uk (Steve_Kilbane)
epl@Kodak.COM (Gene Loriot (epl@Caps.Kodak.COM.))
Casper Dik <casper@fwi.uva.nl>
Birger.Wathne@vest.sdata.no (Birger A. Wathne)
"John Strupp" <strupp@geronimo.drad.umn.edu>
peter.allan@aea.orgn.uk (Peter Allan)
louis@meg.meg.saic.com (Dances on keyboards (Louis Brune))
Jun Wu <jun@crick.ssctr.bcm.tmc.edu>
glenn@uniq.com.au (Glenn Satchell - Uniq Professional Services)
stern@sunrise.East.Sun.COM (Hal Stern - NE Area Systems Engineer)
Eckhard.Rueggeberg@ts.go.dlr.de (Eckhard Rueggeberg)
The general concensus is that Solaris 2.3 can run swapless with
nothing special to be done. However, some swap is needed to
prevent deadlocks when available memory gets scarce.
epl@Kodak.COM was ajusting his swap to zero dynamically while the
machine was running; the machine didn't fall over but a lot of error
messages in the console. Birger.Wathne@vest.sdata.no's Solaris 2.3
was still running when a drive holding the swap failed.
louis@meg.meg.saic.com ran his machine well without swap by accident.
steve@cegelecproj.co.uk was concerned about crash dumps on a
machine with little or no swap. peter.allan@aea.orgn.uk questioned
how one would load MINIROOT on a swapless machine.
glenn@uniq.com.au suggested to try it out by commenting out the
primary swap device entry in /etc/vfstab and rebooting.
My conclusion: I will configure a Solaris 2.3 Sybase server with
512 MB memory and 20 MB swap for the reasons above and due to the
fact that Sybase uses pre-allocated memory size and that no other
memory intensive processes are supposed to run on the server.
Anchi
