From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 8 Mar 2000 23:39:46 +0100 From: Jamie Lokier Subject: Re: Linux responsiveness under heavy load Message-ID: <20000308233946.A9644@pcep-jamie.cern.ch> References: <20000308223851.A9519@pcep-jamie.cern.ch> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: ; from Rik van Riel on Wed, Mar 08, 2000 at 07:26:22PM -0300 Sender: owner-linux-mm@kvack.org Return-Path: To: riel@nl.linux.org Cc: linux-kernel@vger.rutgers.edu, linux-mm@kvack.org List-ID: Rik van Riel wrote: > > A larger priority for page-in I/O due to interactive process too > > might help too. Some modification of Andrea's elevator. But > > that doesn't seem so easy. > > Read requests are easily tied to a process, so this could > be relatively easy. Doing it properly before 2.5 may be a > little difficult though ... A simple flag with each I/O request meaning "high priority due to interactive process I/O". Make the elevator select high priority requests before low ones, with the same sequence number bound for fairness as has recently been implemented. Maybe even a small holdoff time when going from handling a high priority to a low priority request, to give the interactive process a few microseconds to stimulate another page in. (Actually a small holdoff in general between I/O "here" and I/O "far away" might improve overall seek times, orthogonal to priority issues). It does seem too simple to work, but has anyone tried it? -- Jamie -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux.eu.org/Linux-MM/