Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753689AbbHMS6J (ORCPT ); Thu, 13 Aug 2015 14:58:09 -0400 Received: from mx1.redhat.com ([209.132.183.28]:48777 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753175AbbHMS6F (ORCPT ); Thu, 13 Aug 2015 14:58:05 -0400 From: Jeff Moyer To: axboe@kernel.dk, hch@infradead.org Cc: ed.cashin@acm.org, linux-kernel@vger.kernel.org Subject: [PATCH 2/2] block: bump BLK_DEF_MAX_SECTORS to 2560 Date: Thu, 13 Aug 2015 14:57:57 -0400 Message-Id: <1439492277-14638-3-git-send-email-jmoyer@redhat.com> In-Reply-To: <1439492277-14638-1-git-send-email-jmoyer@redhat.com> References: <1439492277-14638-1-git-send-email-jmoyer@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1403 Lines: 37 A value of 2560 (1280k) will accommodate a 10-data-disk stripe write with chunk size 128k. In the testing I've done using iozone, fio, and aio-stress across a number of different storage devices, a value of 1280 does not show a big performance difference from 512, but will hopefully help software RAID setups using SATA disks, as reported by Christoph. NOTE: drivers/block/aoe/aoeblk.c sets its own max_hw_sectors_kb to BLK_DEF_MAX_SECTORS. So, this patch essentially changes aeoblk to Use a larger maximum sector size, and I did not test this. Signed-off-by: Jeff Moyer --- include/linux/blkdev.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 1fd459e1..dbc845f 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1138,7 +1138,7 @@ extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm); enum blk_default_limits { BLK_MAX_SEGMENTS = 128, BLK_SAFE_MAX_SECTORS = 255, - BLK_DEF_MAX_SECTORS = 1024, + BLK_DEF_MAX_SECTORS = 2560, BLK_MAX_SEGMENT_SIZE = 65536, BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL, }; -- 1.8.3.1 -- 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/