From owner-freebsd-fs Tue Mar 20 10:35:21 2001 Delivered-To: freebsd-fs@freebsd.org Received: from fw.wintelcom.net (ns1.wintelcom.net [209.1.153.20]) by hub.freebsd.org (Postfix) with ESMTP id C64F737B71A; Tue, 20 Mar 2001 10:35:14 -0800 (PST) (envelope-from bright@fw.wintelcom.net) Received: (from bright@localhost) by fw.wintelcom.net (8.10.0/8.10.0) id f2KIVUc23476; Tue, 20 Mar 2001 10:31:30 -0800 (PST) Date: Tue, 20 Mar 2001 10:31:30 -0800 From: Alfred Perlstein To: "Michael C . Wu" Cc: Matt Dillon , "Michael C . Wu" , izero@ms26.hinet.net, cross@math.psu.edu, grog@FreeBSD.ORG, fs@FreeBSD.ORG, hackers@FreeBSD.ORG Subject: Re: tuning a VERY heavily (30.0) loaded scerver Message-ID: <20010320103130.Y29888@fw.wintelcom.net> References: <20010320111144.A51924@peorth.iteration.net> <20010320092717.R29888@fw.wintelcom.net> <20010320113818.B52586@peorth.iteration.net> <20010320120112.C52586@peorth.iteration.net> <200103201815.f2KIFR594803@earth.backplane.com> <20010320122350.F52586@peorth.iteration.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <20010320122350.F52586@peorth.iteration.net>; from keichii@iteration.net on Tue, Mar 20, 2001 at 12:23:50PM -0600 X-all-your-base: are belong to us. Sender: owner-freebsd-fs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org * Michael C . Wu [010320 10:27] wrote: > On Tue, Mar 20, 2001 at 10:15:27AM -0800, Matt Dillon scribbled: > | > | :Another problem is that we have around 4000+ processes accessing > | :lots of SHM at the same time.. > | > | How big is 'lots'? If the shared memory segment is smallish, e.g. > | less then 64MB, you should be ok. If it is larger then you will > | have to do some kernel tuning to avoid running out of pmap entries. > > This is exactly what happens to us sometimes. We run out of pmap entries. :) > But what can we tune? If this is a result of the shared memory, then my sysctl should fix it. Be aware, that it doesn't fix it on the fly! You must drop and recreate the shared memory segments. better to reboot actually and set the variable before any shm is allocated. -- -Alfred Perlstein - [bright@wintelcom.net|alfred@freebsd.org] To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-fs" in the body of the message