Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 9 Oct 2001 10:23:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 9 Oct 2001 10:23:16 -0400 Received: from perninha.conectiva.com.br ([200.250.58.156]:35857 "HELO perninha.conectiva.com.br") by vger.kernel.org with SMTP id ; Tue, 9 Oct 2001 10:23:06 -0400 Date: Tue, 9 Oct 2001 11:01:31 -0200 (BRST) From: Marcelo Tosatti To: BALBIR SINGH Cc: Linus Torvalds , Andrea Arcangeli , lkml Subject: Re: pre6 VM issues In-Reply-To: <3BC30701.2060908@wipro.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 9 Oct 2001, BALBIR SINGH wrote: > Most of the traditional unices maintained a pool for each subsystem > (this is really useful when u have the memory to spare), so not matter > what they use memory only from their pool (and if needed peek outside), > but nobody else used the memory from the pool. > > I have seen cases where, I have run out of physical memory on my system, > so I try to log in using the serial console, but since the serial driver > does get_free_page (this most likely fails) and the driver complains back. > So, I had suggested a while back that important subsystems should maintain > their own pool (it will take a new thread to discuss the right size of > each pool). > > Why can't Linux follow the same approach? especially on systems with a lot > of memory. There is nothing which avoids us from doing that (there is one reserved pool I remeber right now: the highmem bounce buffering pool, but that one is a special case due to the way Linux does IO in high memory and its only needed on _real_ emergencies --- it will be removed in 2.5, I hope). In general, its a better approach to share the memory and have a unified pool. If a given subsystem is not using its own "reversed" memory, another subsystems can use it. The problem we are seeing now can be fixed even without the reserved pools. - 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/