From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 9 Aug 2001 15:40:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 9 Aug 2001 15:40:37 -0400 Received: from alfik.ms.mff.cuni.cz ([195.113.19.71]:25870 "EHLO alfik.ms.mff.cuni.cz") by vger.kernel.org with ESMTP id ; Thu, 9 Aug 2001 15:40:22 -0400 Message-ID: <20010809212730.C25162@bug.ucw.cz> Date: Thu, 9 Aug 2001 21:27:30 +0200 From: Pavel Machek To: Alan Cox , "Dirk W. Steinberg" Cc: "linux-kernel@vger.kernel.org" Subject: Re: Swapping for diskless nodes In-Reply-To:

Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.93i In-Reply-To: ; from Alan Cox on Thu, Aug 09, 2001 at 10:08:37AM +0100 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi! > > what is the best/recommended way to do remote swapping via the network > > for diskless workstations or compute nodes in clusters in Linux 2.4?=20 > > Last time i checked was linux 2.2, and there were some races related=20 > > to network swapping back then. Has this been fixed for 2.4? > > The best answer probably is "don't". Networks are high latency things for > paging and paging is latency sensitive. If performance is not an issue then > the nbd driver ought to work. You may need to check it uses the ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Alan, are you saying it should work reliably? > right > GFP_ levels to avoid deadlocks and you might need to up the amount of atomic > pool memory. Hopefully other hacks arent needed There still may be some deadlocks. Swapping over nbd seemed to work for me... until I used mem=8M and did two ping -f's to the victim. Issue is that you not only need to check nbd, you need to check whole network layer, too. Pavel -- I'm pavel@ucw.cz. "In my country we have almost anarchy and I don't care." Panos Katsaloulis describing me w.r.t. patents at discuss@linmodems.org