From owner-freebsd-stable@FreeBSD.ORG Fri Jan 23 09:44:22 2009 Return-Path: Delivered-To: stable@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 117B31065672; Fri, 23 Jan 2009 09:44:22 +0000 (UTC) (envelope-from oleg@lath.rinet.ru) Received: from lath.rinet.ru (lath.rinet.ru [195.54.192.90]) by mx1.freebsd.org (Postfix) with ESMTP id BF8658FC13; Fri, 23 Jan 2009 09:44:21 +0000 (UTC) (envelope-from oleg@lath.rinet.ru) Received: by lath.rinet.ru (Postfix, from userid 222) id BAF427015; Fri, 23 Jan 2009 12:44:20 +0300 (MSK) Date: Fri, 23 Jan 2009 12:44:20 +0300 From: Oleg Bulyzhin To: Luigi Rizzo Message-ID: <20090123094420.GC54838@lath.rinet.ru> References: <20090123081028.GA38763@onelab2.iet.unipi.it> <20090123085337.GB54838@lath.rinet.ru> <20090123092312.GC40642@onelab2.iet.unipi.it> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090123092312.GC40642@onelab2.iet.unipi.it> User-Agent: Mutt/1.5.18 (2008-05-17) Cc: stable@FreeBSD.org, re@FreeBSD.org Subject: Re: backporting dummynet's q_time change ? (svn 184414) X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 23 Jan 2009 09:44:22 -0000 On Fri, Jan 23, 2009 at 10:23:12AM +0100, Luigi Rizzo wrote: > this is also in RELENG_7 but i am not sure whether this workaround > has any drawback e.g., when curr_time passes a 32-bit boundary > there seems to be an incorrect setting of q->numbytes Workaround is fine in average. It may fail for: 1) _very_ idle flow (more than 2^32 ticks) while calculating q->avg 2) any flow once per 2^32 ticks then q_time will be updated and things will be ok again. -- Oleg. ================================================================ === Oleg Bulyzhin -- OBUL-RIPN -- OBUL-RIPE -- oleg@rinet.ru === ================================================================