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, 10 Jan 2001 07:03:41 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 10 Jan 2001 07:03:31 -0500 Received: from colorfullife.com ([216.156.138.34]:8973 "EHLO colorfullife.com") by vger.kernel.org with ESMTP id ; Wed, 10 Jan 2001 07:03:11 -0500 Message-ID: <3A5C4FAC.CA6E46A9@colorfullife.com> Date: Wed, 10 Jan 2001 13:03:56 +0100 From: Manfred Spraul X-Mailer: Mozilla 4.75 [en] (X11; U; Linux 2.2.16-22 i586) X-Accept-Language: en MIME-Version: 1.0 To: mingo@elte.hu CC: linux-kernel@vger.kernel.org Subject: Re: [PLEASE-TESTME] Zerocopy networking patch, 2.4.0-1 In-Reply-To: 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 Ingo Molnar wrote: > > On Wed, 10 Jan 2001, Manfred Spraul wrote: > > > That means sendmsg() changes the page tables? I measures > > smp_call_function on my Dual Pentium 350, and it took around 1950 cpu > > ticks. > > well, this is a performance problem if you are using threads. For normal > processes there is no need for a SMP cross-call, there TLB flushes are > local only. > But that would be ugly as hell: so apache 2.0 would become slower with MSG_NOCOPY, whereas samba 2.2 would become faster. Is is possible to move the responsibility for maitaining the copy to the caller? e.g. use msg_control, and then the caller can request either that a signal is sent when that data is transfered, or that a variable is set to 0. -- Manfred - 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/