From owner-freebsd-questions Mon Nov 24 08:54:06 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id IAA14986 for questions-outgoing; Mon, 24 Nov 1997 08:54:06 -0800 (PST) (envelope-from owner-freebsd-questions) Received: from implode.root.com (implode.root.com [198.145.90.17]) by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id IAA14981 for ; Mon, 24 Nov 1997 08:54:03 -0800 (PST) (envelope-from root@implode.root.com) Received: from implode.root.com (localhost [127.0.0.1]) by implode.root.com (8.8.5/8.8.5) with ESMTP id IAA06743; Mon, 24 Nov 1997 08:55:56 -0800 (PST) Message-Id: <199711241655.IAA06743@implode.root.com> To: "Gregory, Scott, SrA, SAF/AADXT" cc: "'freebsd-questions@freebsd.org'" Subject: Re: Mbuf allocation or lack there of In-reply-to: Your message of "Mon, 24 Nov 1997 08:34:13 EST." From: David Greenman Reply-To: dg@root.com Date: Mon, 24 Nov 1997 08:55:56 -0800 Sender: owner-freebsd-questions@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk >Thanks for the info, but now I have a few more questions. > >1. I specified that "NMBCLUSTERS=4096". Does this mean that the system >has 4096 Mbuf clusters available? Yes. >2. If #1 is yes, then why did I get an "out of mbuf clusters" error >when the system had only used 1136? (I was reading the numbers >correctly, I just explained it poorly :-) ) It sounds like you either forgot to do a 'config' after changing the kernel config file, or didn't install the new kernel after it was rebuilt. >3. Does the generic kernel (with max users set to 100 and maxmem set to >96megs) allocate more mbufs than my custom kernel with maxusers set to >128 and NMBCLUSTERS set to 4096? The reason I ask this is because the >slightly modified kernel was able to attain a maximum of 2318 mbufs >where as the modified kernel was only able to get to 1136. No, GENERIC is set to 10 users which would yield about 672 mbuf clusters. The formula in the absense of NMBCLUSTERS is (512 + maxusers * 16). >4. What would you suggest I set NMBCLUSTERS and/or maxusers to? 4096 and 128 is probably fine for a medium loaded WWW server. It all depends on how heavy the traffic is. -DG David Greenman Core-team/Principal Architect, The FreeBSD Project