From owner-freebsd-fs Fri Mar 23 5:44:58 2001 Delivered-To: freebsd-fs@freebsd.org Received: from fledge.watson.org (fledge.watson.org [204.156.12.50]) by hub.freebsd.org (Postfix) with ESMTP id 9974037B71F; Fri, 23 Mar 2001 05:44:52 -0800 (PST) (envelope-from robert@fledge.watson.org) Received: from fledge.watson.org (robert@fledge.pr.watson.org [192.0.2.3]) by fledge.watson.org (8.11.1/8.11.1) with SMTP id f2NDi9h27008; Fri, 23 Mar 2001 08:44:29 -0500 (EST) (envelope-from robert@fledge.watson.org) Date: Fri, 23 Mar 2001 08:44:09 -0500 (EST) From: Robert Watson X-Sender: robert@fledge.watson.org To: "Alexey V. Neyman" Cc: "Michael C . Wu" , fs@FreeBSD.ORG, hackers@FreeBSD.ORG Subject: Re: tuning a VERY heavily (30.0) loaded s cerver In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-fs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Fri, 23 Mar 2001, Alexey V. Neyman wrote: > On Thu, 22 Mar 2001, Michael C . Wu wrote: > > >(Why is vfs.vmiodirenable=1 not enabled by default?) > By the way, is there any all-in-one-place description of sysctl tuneables? > Looking all the man pages and collecting notices about MIB variables seems > rather tiresome and, I think, pointless. I doubt if they are all > documented in man pages. sysctl(3) describes a number of the constant-named sysctl variables, and a number of sysctl's are described in the man pages associated with the features tweaked by the sysctl's. For example, the jail(8) man page describes the jail.* namespace. However, you're right that there are vast hoards of under-documented sysctl's. That said, probably only the "tweakable" (writable) sysctl's need to be documented in the general case, since many are used for the sole purpose of exporting kernel data for supported interfaces, whereas the sysctl's are subject to change. For example, a large number of read-only sysctl's were introduced to support the non-setgid-kmem operation of top, systat, and various other *stat's recently. Also, many sysctl's are "self-documenting", in that the declaration of the sysctl macros in-kernel include a description field. I don't think sysctl(8) currently knows how to read that field, but if you look at the SYSCTL definitions in the kernel source, they're probably a decent starting point. A magic script to extract the sysctl names, types, and descriptions might be useful.. Robert N M Watson FreeBSD Core Team, TrustedBSD Project robert@fledge.watson.org NAI Labs, Safeport Network Services To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-fs" in the body of the message