From owner-freebsd-current@FreeBSD.ORG Fri Mar 27 14:32:32 2009 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id E8A63106564A for ; Fri, 27 Mar 2009 14:32:32 +0000 (UTC) (envelope-from prashant.vaibhav@gmail.com) Received: from wf-out-1314.google.com (wf-out-1314.google.com [209.85.200.170]) by mx1.freebsd.org (Postfix) with ESMTP id BBAD68FC15 for ; Fri, 27 Mar 2009 14:32:32 +0000 (UTC) (envelope-from prashant.vaibhav@gmail.com) Received: by wf-out-1314.google.com with SMTP id 24so1194227wfg.7 for ; Fri, 27 Mar 2009 07:32:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:cc:content-type; bh=IooPuzI9uJ5jBfXDw2ZSnIg/vvBX9oAj9NBllEW9diE=; b=qAZhXsade+SzAja3pHgVLdgAj544BCcnAGAd1YRFZRIgriVYZOXG4ca1D73KLPIC8r AqFp0cXs4XSBX5jUjXWPKQWewHBC9xbs77NAtX3ScDWI5c+2zxvD5xZQ3OlcAuD0VDfq I4e7EusmOOhAXt8HkmhxqBy0IpWUbfn86rCjQ= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; b=O+SAfJaaMvJHPBhbjFLEUJEjTC34u7UTttzQ5V3Y3uMwt5TSljHW0GGIqmyG6A02Qh znubj6D5lmTU5xV5I0cMX1Uazct0Cpf2PZGYgr1QvAEqxJaS8YTkrR6h04JDbJfSZLt5 cFdcZ9uX1oUDFUE7aN74QHXNPOYFldB1qsbmA= MIME-Version: 1.0 Received: by 10.142.242.8 with SMTP id p8mr934097wfh.60.1238164352344; Fri, 27 Mar 2009 07:32:32 -0700 (PDT) In-Reply-To: <49CCDD7D.FA83BF14@kuzbass.ru> References: <17560ccf0903260551v1f5cba9eu87727c0bae7baa3@mail.gmail.com> <49CCDD7D.FA83BF14@kuzbass.ru> Date: Fri, 27 Mar 2009 20:02:32 +0530 Message-ID: <17560ccf0903270732x23970ad4j42c81511a97a1ce8@mail.gmail.com> From: Prashant Vaibhav To: Eugene Grosbein Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: freebsd-current@freebsd.org Subject: Re: Improving the kernel/i386 timecounter performance (GSoC proposal) X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 27 Mar 2009 14:32:33 -0000 Eugene, No I am not. Looking at it now. I'm not familiar with a lot of things specific to the freebsd kernel actually, but familiar with tsc/timing stuff in general and xnu in particular. After seeing this in the gsoc ideas list I decided to apply, assuming it would map well to freebsd too. Best, Prashant 2009/3/27 Eugene Grosbein > Prashant Vaibhav wrote: > > > The primary idea is to improve the performance and resolution of > > gettimeofday() and friends by creating a efficient userspace > implementation > > of these functions, along with some supporting modifications to the > kernel. > > Are you aware of CLOCK_*_FAST family of timecounters present > in FreeBSD 7.x? If not, you may want to take a look: > > http://www.freebsd.org/cgi/cvsweb.cgi/src/sys/sys/time.h#rev1.71 > > Eugene Grosbein >