Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965622AbXBTARl (ORCPT ); Mon, 19 Feb 2007 19:17:41 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965614AbXBTARF (ORCPT ); Mon, 19 Feb 2007 19:17:05 -0500 Received: from rgminet01.oracle.com ([148.87.113.118]:59744 "EHLO rgminet01.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965642AbXBTAQI (ORCPT ); Mon, 19 Feb 2007 19:16:08 -0500 Date: Mon, 19 Feb 2007 19:13:51 -0500 From: Chris Mason To: Miklos Szeredi Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: dirty balancing deadlock Message-ID: <20070220001351.GJ6133@think.oraclecorp.com> References: <20070218125307.4103c04a.akpm@linux-foundation.org> <20070218145929.547c21c7.akpm@linux-foundation.org> <20070218155916.0d3c73a9.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.12-2006-07-14 X-Whitelist: TRUE X-Whitelist: TRUE X-Brightmail-Tracker: AAAAAQAAAAI= Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1243 Lines: 31 On Mon, Feb 19, 2007 at 06:11:55PM +0100, Miklos Szeredi wrote: > How about this? > > Solves the FUSE deadlock, but not the throttle_vm_writeout() one. > I'll try to tackle that one as well. > > If the per-bdi dirty counter goes below 16, balance_dirty_pages() > returns. > > Does the constant need to tunable? If it's too large, then the global > threshold is more easily exceeded. If it's too small, then in a tight > situation progress will be slower. Ok, what is supposed to happen here is that filesystems are supposed to be throttled from making more dirty pages when the system is over the threshold. Even if filesystem A doesn't have much to contribute, and filesystem B is the cause of 99% of the dirty pages, the goal of the threshold is to prevent more dirty data from happening, and filesystem A should block. But, with the producer consumer setup of fuse, I think this is a pretty good compromise. 16 dirty/writeback pages shouldn't hurt the overall limits too badly. -chris - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/