From owner-svn-src-head@FreeBSD.ORG Sat Mar 21 14:27:43 2015 Return-Path: Delivered-To: svn-src-head@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id C9A50AB4; Sat, 21 Mar 2015 14:27:43 +0000 (UTC) Received: from kib.kiev.ua (kib.kiev.ua [IPv6:2001:470:d5e7:1::1]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 38231CA3; Sat, 21 Mar 2015 14:27:43 +0000 (UTC) Received: from tom.home (kostik@localhost [127.0.0.1]) by kib.kiev.ua (8.14.9/8.14.9) with ESMTP id t2LERcQU001456 (version=TLSv1/SSLv3 cipher=DHE-RSA-CAMELLIA256-SHA bits=256 verify=NO); Sat, 21 Mar 2015 16:27:38 +0200 (EET) (envelope-from kostikbel@gmail.com) DKIM-Filter: OpenDKIM Filter v2.9.2 kib.kiev.ua t2LERcQU001456 Received: (from kostik@localhost) by tom.home (8.14.9/8.14.9/Submit) id t2LERcF8001455; Sat, 21 Mar 2015 16:27:38 +0200 (EET) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: tom.home: kostik set sender to kostikbel@gmail.com using -f Date: Sat, 21 Mar 2015 16:27:38 +0200 From: Konstantin Belousov To: Kubilay Kocak Subject: Re: svn commit: r280308 - head/sys/fs/devfs Message-ID: <20150321142737.GJ2379@kib.kiev.ua> References: <201503210114.t2L1ECcB075556@svn.freebsd.org> <550D5D49.6020503@FreeBSD.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <550D5D49.6020503@FreeBSD.org> User-Agent: Mutt/1.5.23 (2014-03-12) X-Spam-Status: No, score=-2.0 required=5.0 tests=ALL_TRUSTED,BAYES_00, DKIM_ADSP_CUSTOM_MED,FREEMAIL_FROM,NML_ADSP_CUSTOM_MED autolearn=no autolearn_force=no version=3.4.0 X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on tom.home Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org, src-committers@freebsd.org, Xin LI X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 21 Mar 2015 14:27:43 -0000 On Sat, Mar 21, 2015 at 11:00:09PM +1100, Kubilay Kocak wrote: > On 21/03/2015 12:14 PM, Xin LI wrote: > > Author: delphij > > Date: Sat Mar 21 01:14:11 2015 > > New Revision: 280308 > > URL: https://svnweb.freebsd.org/changeset/base/280308 > > > > Log: > > Disable timestamping on devfs read/write operations by default. > > > > Currently we update timestamps unconditionally when doing read or > > write operations. This may slow things down on hardware where > > reading timestamps is expensive (e.g. HPET, because of the default > > vfs.timestamp_precision setting is nanosecond now) with limited > > benefit. > > > > A new sysctl variable, vfs.devfs.dotimes is added, which can be > > set to non-zero value when the old behavior is desirable. > > Perhaps *devfs_timestamp_update* is a better name. thoughts? > > If something shorter is desired: devfs_ts_update might be ok, though I > prefer the former. > > Let's not forget these are user visible system control knobs, not just > code variables, though I do understand the desire to shorten them, and > that we do have descriptions for them ... mostly :) should it be vfs.devfs.devfs_ts_devfs_ts_devfs_update_devfs so that user is _absolutely_ sure that it is devfs related, if 'devfs' used only one time in the MIB prevents him from realizing this ?