From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Heffner Subject: Re: [PATCH] fix up sysctl_tcp_mem initialization Date: Wed, 15 Nov 2006 12:46:00 -0500 Message-ID: <455B5258.5090504@psc.edu> References: <455A20BD.6010508@psc.edu> <20061114.203118.35665382.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org Return-path: Received: from mailer1.psc.edu ([128.182.58.100]:32201 "EHLO mailer1.psc.edu") by vger.kernel.org with ESMTP id S1030736AbWKORqF (ORCPT ); Wed, 15 Nov 2006 12:46:05 -0500 To: David Miller In-Reply-To: <20061114.203118.35665382.davem@davemloft.net> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org David Miller wrote: >> However, I wonder if we want to set this differently than the way this >> patch does it. Depending on how far off the memory size is from a power >> of two (exactly equal to a power of two is the worst case), and if total >> memory <128M, it can be substantially less than 3/4. > > Longer term, yes, probably a better way exists. > > So you concern is that when we round to a power of 2 like we do > now, we often mis-shoot? I'm not that concerned about it, but basically yes, there are big (x2) jumps on power-of-two memory size boundaries. There's also a bigger (x8) discontinuity at 128k pages. It could be smoother. -John