Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 19 Mar 2002 11:38:37 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 19 Mar 2002 11:38:29 -0500 Received: from tmr-02.dsl.thebiz.net ([216.238.38.204]:9996 "EHLO gatekeeper.tmr.com") by vger.kernel.org with ESMTP id ; Tue, 19 Mar 2002 11:38:10 -0500 Date: Tue, 19 Mar 2002 11:35:39 -0500 (EST) From: Bill Davidsen To: Daniel Phillips cc: Linus Torvalds , linux-kernel@vger.kernel.org Subject: Re: [Lse-tech] Re: 10.31 second kernel compile In-Reply-To: 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 Sat, 16 Mar 2002, Daniel Phillips wrote: > It breaks down somewhat as virtual memory range goes way beyond 4GB. > There's the relatively minor issue of extra levels of tree traversal, > currently limited to 4 by AMD's architecture but not so limited on other > architectures. A bigger problem is what to do about internal fragmentation > in the page table tree, say if somebody mmaps a 2 TB sparse file, then writes > one byte every 2 meg. Bang, 4 gig worth of page tables, this is probably not > what we want. IMHO, 'don't do that then' isn't a reasonable response. Perhaps not, but "if you do that it will be slow" is a reasonable response when any operation requires an unusual resource to complete. The best solution is to reduce the resources needed by being clever, but the next best is to prevent one process from beating the machine to death for all others (if any). -- bill davidsen CTO, TMR Associates, Inc Doing interesting things with little computers since 1979. - 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/