From owner-freebsd-hackers@FreeBSD.ORG Sat Apr 5 01:49:02 2003 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 0B18037B401 for ; Sat, 5 Apr 2003 01:49:02 -0800 (PST) Received: from mail.econolodgetulsa.com (mail.econolodgetulsa.com [198.78.66.163]) by mx1.FreeBSD.org (Postfix) with ESMTP id 9DF1843F85 for ; Sat, 5 Apr 2003 01:49:01 -0800 (PST) (envelope-from user@mail.econolodgetulsa.com) Received: from mail (mail [198.78.66.163])h359n3eq034593 for ; Sat, 5 Apr 2003 01:49:03 -0800 (PST) (envelope-from user@mail.econolodgetulsa.com) Date: Sat, 5 Apr 2003 01:49:03 -0800 (PST) From: Josh Brooks To: freebsd-hackers@freebsd.org Message-ID: <20030405011856.T11740-100000@mail.econolodgetulsa.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Subject: KVA suggestions on 4gig+2gig memory system ? X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 05 Apr 2003 09:49:02 -0000 Hello, I have a new system that has 4gigs of physical memory ... and I am concerned about running into problems due to running out of KVM. I am running FreeBSD 4.8, and in addition to 4gigs of ram, I have configured 2gigs of swap space. The system does not swap much at all, but I need it there just in case. I will be upping shm as follows for database use: options SHMSEG=256 options SEMMNI=384 options SEMMNU=256 options SEMMAP=256 options SEMMNS=512 options SHMMAXPGS=12288 options SHMMAX="(SHMMAXPGS*PAGE_SIZE+1)" and the system will be used as a large multiuser system with a lot of different processes running (1200-1600 processes) So my questions are: 1. Should I change the default value of KVA_PAGES ? I have another system running the same processes and same load as this one, and it does not specify any KVA_PAGES in the kernel config, so it is using the default value - and it works wonderfully. BUT, this other system has 3 physical + 2 swap, and not 4 physical. So will that extra gig of physical demand altering KVA_PAGES ? 2. If I should change it, suggestions ? The default is 260, and I believe 512 splits memory in half ... perhaps 512 is a good number ? 3. are there any other tunables to worry about ? I think the key here is that I am running wonderfully on the 3+2 system without any tunings for KVA, so I am just looking for advice on what the extra gig of physical does for me...it may be useful to mention that the original 3+2 system has 40% swap usage ... but maybe that doesn't matter. thanks!