Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 6 Feb 2001 13:59:12 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 6 Feb 2001 13:59:02 -0500 Received: from chiara.elte.hu ([157.181.150.200]:27658 "HELO chiara.elte.hu") by vger.kernel.org with SMTP id ; Tue, 6 Feb 2001 13:58:43 -0500 Date: Tue, 6 Feb 2001 19:58:04 +0100 (CET) From: Ingo Molnar Reply-To: To: Ben LaHaise Cc: "Stephen C. Tweedie" , Linus Torvalds , Alan Cox , Manfred Spraul , Steve Lord , Linux Kernel List , , Ingo Molnar Subject: Re: [Kiobuf-io-devel] RFC: Kernel mechanism: Compound event wait 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 Tue, 6 Feb 2001, Ben LaHaise wrote: > - reduce the overhead in submitting block ios, especially for > large ios. Look at the %CPU usages differences between 512 byte > blocks and 4KB blocks, this can be better. my system is already submitting 4KB bhs. If anyone's raw-IO setup submits 512 byte bhs thats a problem of the raw IO code ... > - make asynchronous io possible in the block layer. This is > impossible with the current ll_rw_block scheme and io request > plugging. why is it impossible? > You mentioned non-spindle base io devices in your last message. Take > something like a big RAM disk. Now compare kiobuf base io to buffer > head based io. Tell me which one is going to perform better. roughly equal performance when using 4K bhs. And a hell of a lot more complex and volatile code in the kiobuf case. Ingo - 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/