From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 1 Nov 2000 16:36:28 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 1 Nov 2000 16:36:18 -0500 Received: from vger.timpanogas.org ([207.109.151.240]:61709 "EHLO vger.timpanogas.org") by vger.kernel.org with ESMTP id ; Wed, 1 Nov 2000 16:36:15 -0500 Message-ID: <3A008BEB.D33EE394@timpanogas.org> Date: Wed, 01 Nov 2000 14:32:27 -0700 From: "Jeff V. Merkey" Organization: TRG, Inc. X-Mailer: Mozilla 4.7 [en] (WinNT; I) X-Accept-Language: en MIME-Version: 1.0 To: Daniel Phillips CC: linux-kernel@vger.kernel.org Subject: Re: 2.2.18Pre Lan Performance Rocks! In-Reply-To: <39FF3D53.C46EB1A8@timpanogas.org> <20001031140534.A22819@work.bitmover.com> <39FF4488.83B6C1CE@timpanogas.org> <20001031142733.A23516@work.bitmover.com> <39FF49C8.475C2EA7@timpanogas.org> <20001101023010.G13422@athlon.random> <20001031183809.C9733@.timpanogas.org> <20001101164106.F9774@athlon.random> <3A005217.88D2CA0D@timpanogas.org> <3A005476.17F0F253@timpanogas.org> <20001101190732.A19767@athlon.random> <3A00621F.7CC77F5A@timpanogas.org> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Daniel Phillips wrote: > > "Jeff V. Merkey" wrote: > > > > Andrea Arcangeli wrote: > > > > > > Speaking only for myself: on the technical side I don't think you can't be much > > > faster than moving the performance critical services into the kernel and by > > > skipping the copies (infact I also think that for fileserving skipping the > > > copies and making sendfile to work and to work in zero copy will be enough). > > > So I don't think losing robusteness this way can be explained in any technical > > > way and no, it's not by showing me money that you'll convince me that's a good > > > idea. > > > > This would help, but not as much as full ring 0. > > My experience is that I can get pretty much the same performance in ring > 3 as ring 0 as long as I don't reload segment registers or take CR3. Is > this right, or am I missing some fundamental kind of ring 3 overhead? > > Even in ring 0, you can mostly protect processes from each other using > segments: if you don't reload the segments you can restrict damage to > your own segment. It's not 100% safety but it is an enormous > improvement over running in the same address space as the OS kernel. I > don't have any problem at all with the idea of running a lot of parallel > tasks in the same address space: the safety of this comes down to the > compiler you use to compile the processes. If the compiler doesn't have > ops that let processes damage each other then you won't get damage, > assuming no bugs in your underlying implementation. > > BTW, let me add my 'me too': go for it, there is obviously a pot of gold > there, just don't let Sauron^H^H^H^H^H^H Bill get to it first. Amen to that one. BTW. The package we mailed out to you from Brian went yesterday. Let me know when it arrives. I sent it to the address in Berlin you provided. :-) Jeff > > -- > Daniel > - > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > Please read the FAQ at http://www.tux.org/lkml/ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/