From owner-freebsd-questions Mon Jan 6 16:10:18 2003 Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 11C2337B401 for ; Mon, 6 Jan 2003 16:10:17 -0800 (PST) Received: from rapidash.its.hawaii.edu (rapidash.its.hawaii.edu [128.171.94.83]) by mx1.FreeBSD.org (Postfix) with ESMTP id 5A68B43EA9 for ; Mon, 6 Jan 2003 16:10:16 -0800 (PST) (envelope-from jljennin@hawaii.edu) Received: from conversion-daemon.mail.hawaii.edu by mail.hawaii.edu (iPlanet Messaging Server 5.1 HotFix 1.4 (built Aug 5 2002)) id <0H8B00G01HNF0H@mail.hawaii.edu>; Mon, 06 Jan 2003 14:10:10 -1000 (HST) Received: from hawaii.edu (mail.hawaii.edu [128.171.94.84]) by mail.hawaii.edu (iPlanet Messaging Server 5.1 HotFix 1.4 (built Aug 5 2002)) with ESMTP id <0H8B00G9SHS5AX@mail.hawaii.edu>; Mon, 06 Jan 2003 14:09:41 -1000 (HST) Received: from [66.157.189.195] by mail.hawaii.edu (mshttpd); Mon, 06 Jan 2003 18:09:41 -0600 Date: Mon, 06 Jan 2003 18:09:41 -0600 From: Jonathan Louis Jennings Subject: Problem with buffer space To: freebsd-questions@FreeBSD.ORG Message-id: <3ecb2c3e5dd4.3e5dd43ecb2c@hawaii.edu> MIME-version: 1.0 X-Mailer: iPlanet Messenger Express 5.1 HotFix 1.4 (built Aug 5 2002) Content-type: text/plain; charset=us-ascii Content-language: en Content-transfer-encoding: 7bit Content-disposition: inline X-Accept-Language: en Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Greetings! My friend and I are running FreeBSD 4.7 and are connected to a DSL line with an Alcatel Speedtouch USB ADSL modem. We are able to successfully establish a connection to our DSL provider and can successfully access all network services. The box in question serves as a gateway for a LAN (using ppp nat) and the internal clients are capable of accessing all network services as well. However, periodically, all network services become heavily lagged and eventually cease functioning entirely. At such times, ping reports the following: "sendto: buffer space not available" The maximum transmission unit size for our ppp interface is set to 1500. (this may have no relation to the problem) Also, after about 10 minutes the buffer clears and is capable of sending and receiving packets again. After using the network for a given period, the buffer again becomes full and all network services lag heavily and eventually cease functioning entirely. And the process continues in this manner indefinitely, even after rebooting. We compiled a new kernel, raising "maxusers" to 64, but the problem still persists. I have researched buffer space allocation and cannot find any articles or explanations for beginners. (I have no experience with the concept of buffers and how they work, etc.) In any case, I found two options in the LINT kernel: NMBCLUSTERS and NMBUFS. Are these two related to raising the amount of TCP buffer space? If so, how might I determine what values to use for the above two options? Also, if the above two options are not related, where might I read about buffer space (particularly sockets, tcp, etc) and how might I fix the problem? Any help is greatly appreciated. Thanks in advance, John jljennin at hawaii dot edu To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message