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>From: "Mike Schmidt" <address@hidden> >Organization: UCAR/Unidata >Keywords: 200306091657.h59GvRLd029618 McIDAS-XCD FreeBSD shared memory Mike (with CC to Mark Tucker of Lyndon State), re: shared memory tuning on FreeBSD >sysctl -A > and >man sysctl.conf Since the shared memory parameters are only read when the system goes from single user to multi user mode, I added the setting of shared memory max to /etc/sysctl.conf on one of our FreeBSD machines (FreeBSD emo.unidata.ucar.edu 4.7-STABLE FreeBSD 4.7-STABLE): # $FreeBSD: src/etc/sysctl.conf,v 1.1.2.3 2002/04/15 00:44:13 dougb Exp $ # # This file is read when going to multi-user and its contents piped thru # ``sysctl'' to adjust kernel values. ``man 5 sysctl.conf'' for details. # kern.ipc.shmmax=536870912 and then rebooted. After it came back up, things look like what was expected: /local/ldm% sysctl -A | grep shm kern.ipc.shmmax: 536870912 kern.ipc.shmmin: 1 kern.ipc.shmmni: 192 kern.ipc.shmseg: 128 kern.ipc.shmall: 8192 kern.ipc.shm_use_phys: 0 Thanks for the tuning help! Tom >From address@hidden Tue Jun 10 08:41:27 2003 Tom, One clarification -- while the file /etc/sysctl.conf is read only once as you specified, many of the kernel tunables can be set on the fly thus averting a reboot. I'd make the change to /etc/sysctl.conf and then make the changes to the running kernel, one at a time; sysctl kern.ipc.shmmax=536870912 mike >From address@hidden Tue Jun 10 12:21:32 2003 > >sysctl -A > > and > >man sysctl.conf > > Since the shared memory parameters are only read when > the system goes from single user to multi user mode, I added the setting > of shared memory max to /etc/sysctl.conf on one of our FreeBSD > machines (FreeBSD emo.unidata.ucar.edu 4.7-STABLE FreeBSD 4.7-STABLE): > > # $FreeBSD: src/etc/sysctl.conf,v 1.1.2.3 2002/04/15 00:44:13 dougb Exp $ > # > # This file is read when going to multi-user and its contents piped thru > # ``sysctl'' to adjust kernel values. ``man 5 sysctl.conf'' for details. > # > kern.ipc.shmmax=536870912 Tom, This seems to work as advertised. Thanks. -- Mark Tucker Meteorology Dept. Systems Administrator Lyndon State College http://apollo.lsc.vsc.edu address@hidden (802)-626-6328