From owner-freebsd-stable@FreeBSD.ORG Thu Mar 4 11:20:29 2004 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 444B516A4CE for ; Thu, 4 Mar 2004 11:20:29 -0800 (PST) Received: from carver.gumbysoft.com (carver.gumbysoft.com [66.220.23.50]) by mx1.FreeBSD.org (Postfix) with ESMTP id 3A12D43D41 for ; Thu, 4 Mar 2004 11:20:29 -0800 (PST) (envelope-from dwhite@gumbysoft.com) Received: by carver.gumbysoft.com (Postfix, from userid 1000) id 31A8672DCB; Thu, 4 Mar 2004 11:20:29 -0800 (PST) Received: from localhost (localhost [127.0.0.1]) by carver.gumbysoft.com (Postfix) with ESMTP id 2CB3572DB5; Thu, 4 Mar 2004 11:20:29 -0800 (PST) Date: Thu, 4 Mar 2004 11:20:29 -0800 (PST) From: Doug White To: mikej@rogers.com In-Reply-To: <20040304145356.EWCI144376.web02-imail.rogers.com@localhost> Message-ID: <20040304111724.K21028@carver.gumbysoft.com> References: <20040304145356.EWCI144376.web02-imail.rogers.com@localhost> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE cc: stable@freebsd.org Subject: Re: Semaphore scaling X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 04 Mar 2004 19:20:29 -0000 Don't crosspost lists. Thanks. On Thu, 4 Mar 2004 mikej@rogers.com wrote: > I am running an application (Plesk) on a 4.9 system that is eating up > all the semaphores and as a result some processes can=92t run. I have > contacted the software company, and they asked me to increase the > semaphore limits in the kernel. However their suggested settings seemed > very unproportional to me. > > So my question is, how should I adjust the values, while keeping things > in proportion? I wish to increase the default semaphore limit of 10 to > 20. Can I simply double the semaphore related values? The semaphore tunables aren't quite as obvious as they look. There are limits on the size of various clusters of things whos usage is heavily application-dependent. That being said, FreeBSD traditionally has very low SYSVSHM/SEM/MSG limits, so doubling them should be safe. I suggest using the ipcs(8) command to monitor the usage and adjust accordingly. The Plesk-supplied limits seem OK to me too. I've put Oracle-sized values in there and haven't had any bad effects .. yet :) Note that you can adjust these with loader tunables as well, if you don't want to rebuild the kernel. They have the same name as the sysctls that show the current values in kern.ipc. --=20 Doug White | FreeBSD: The Power to Serve dwhite@gumbysoft.com | www.FreeBSD.org