From owner-freebsd-net@FreeBSD.ORG Tue Apr 16 05:57:01 2013 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.FreeBSD.org [8.8.178.115]) by hub.freebsd.org (Postfix) with ESMTP id 16D78980; Tue, 16 Apr 2013 05:57:01 +0000 (UTC) (envelope-from brde@optusnet.com.au) Received: from fallbackmx08.syd.optusnet.com.au (fallbackmx08.syd.optusnet.com.au [211.29.132.10]) by mx1.freebsd.org (Postfix) with ESMTP id A72F7E1D; Tue, 16 Apr 2013 05:56:59 +0000 (UTC) Received: from mail10.syd.optusnet.com.au (mail10.syd.optusnet.com.au [211.29.132.191]) by fallbackmx08.syd.optusnet.com.au (8.13.1/8.13.1) with ESMTP id r3G5urRE026761; Tue, 16 Apr 2013 15:56:53 +1000 Received: from c211-30-173-106.carlnfd1.nsw.optusnet.com.au (c211-30-173-106.carlnfd1.nsw.optusnet.com.au [211.30.173.106]) by mail10.syd.optusnet.com.au (8.13.1/8.13.1) with ESMTP id r3G5ueud025474 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Tue, 16 Apr 2013 15:56:42 +1000 Date: Tue, 16 Apr 2013 15:56:40 +1000 (EST) From: Bruce Evans X-X-Sender: bde@besplex.bde.org To: sbruno@freebsd.org Subject: Re: bge(4) sysctl tuneables -- a blast from the past. In-Reply-To: <1366065356.1350.7.camel@localhost> Message-ID: <20130416152121.G904@besplex.bde.org> References: <1365781568.1418.1.camel@localhost> <20130413200512.G1165@besplex.bde.org> <1366065356.1350.7.camel@localhost> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed X-Optus-CM-Score: 0 X-Optus-CM-Analysis: v=2.0 cv=HfxM1V48 c=1 sm=1 a=vYrNp6gXSs8A:10 a=kj9zAlcOel0A:10 a=PO7r1zJSAAAA:8 a=JzwRw_2MAAAA:8 a=_Js9cBt6JEEA:10 a=6I5d2MoRAAAA:8 a=ff2JBTCXWveTg0XuEZwA:9 a=CjuIK1q_8ugA:10 a=TEtd8y5WR3g2ypngnwZWYw==:117 Cc: "pyunyh@gmail.com" , "freebsd-net@freebsd.org" , bde X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 16 Apr 2013 05:57:01 -0000 On Mon, 15 Apr 2013, Sean Bruno wrote: >> FreeBSD has too many knobs, but it would be nice if the bge defaults weren't >> so broken, so that they don't need overriding. > > So many knobs ... well here's more. :-) Yes, adding more knobs would subtract value. > http://people.freebsd.org/~sbruno/bge_config_update.txt > > At least this gets a man page update with references to manuals. I didn't notice before that these are tunables and not sysctls. That's much more broken. Actually tuning using them like I do with sysctls would take ~10000 reboots. Tunables are bogus for anything that isn't needed for booting. Optimizations are needed for booting. Technical bugs include: - wrong defaults are claimed for *coal_ticks. The defaults are 150, but are claimed to be 150 milliseconds. These values are dimensionless, but since ticks take 1 microsecond each, 150 gives 150 microseconds, not 150 milliseconds. - *coal_bds is claimed to be a count of packes (sic). Actually, it is a count of buffer descriptors. Small packets take 1 bd, but normal packets take 2, and jumbo packets many (?). The best tuning may be depend on the average bds/packet. - the new tunables are in the wrong namespace (hw instead of dev) - the new tunables are too global (bge instead of bge.N) There are only 2 bge tunables now, and they only have half of these bugs: - hw.bge.allow_asf is in the wrong namespace - hw.bge.allow_asf is too global - dev.bge.%d.msi seems to be correct. Both of the old tunables are needed for boot-time configuration. Bruce