Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755079AbYGMNfV (ORCPT ); Sun, 13 Jul 2008 09:35:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754441AbYGMNer (ORCPT ); Sun, 13 Jul 2008 09:34:47 -0400 Received: from mx1.redhat.com ([66.187.233.31]:60369 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754466AbYGMNeq (ORCPT ); Sun, 13 Jul 2008 09:34:46 -0400 Date: Sun, 13 Jul 2008 09:34:33 -0400 (EDT) From: Mikulas Patocka X-X-Sender: mpatocka@devserv.devel.redhat.com To: Andi Kleen cc: sparclinux@vger.kernel.org, linux-kernel@vger.kernel.org, Jens Axboe Subject: Re: [SUGGESTION]: drop virtual merge accounting in I/O requests In-Reply-To: <87iqvb2skz.fsf@basil.nowhere.org> Message-ID: References: <87iqvb2skz.fsf@basil.nowhere.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 880 Lines: 22 > Mikulas Patocka writes: > >> I'm getting crashes with InitIO A100u2w controller on Sparc64 (I had >> to fix the endianity issues in the driver, but that's unrelated). > > x86-64 (and powerpc) solved this a long time ago by only doing > opportunistic merging: as in don't announce to the block layer > that you can merge, but try to merge anyways. This way SG lists > are not necessarily filled completely, but it's still better > than overflowing them in some rare cases. > > -Andi There's option "biomerge" that enables that feature. I'm wondering, if there's some situation when it should be used. Mikulas -- 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/