From mboxrd@z Thu Jan 1 00:00:00 1970 From: Artem Blagodarenko Subject: [PATCH] ext4: preload block group descriptors Date: Mon, 20 Feb 2017 19:45:53 +0300 Message-ID: <1487609153-3367-1-git-send-email-artem.blagodarenko@gmail.com> Cc: alexey.lyashkov@gmail.com, Andrew Perepechko To: linux-ext4@vger.kernel.org Return-path: Received: from mail-pg0-f68.google.com ([74.125.83.68]:35172 "EHLO mail-pg0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752846AbdBTQri (ORCPT ); Mon, 20 Feb 2017 11:47:38 -0500 Received: by mail-pg0-f68.google.com with SMTP id 1so6401325pgz.2 for ; Mon, 20 Feb 2017 08:47:38 -0800 (PST) Sender: linux-ext4-owner@vger.kernel.org List-ID: From: Andrew Perepechko With enabled meta_bg option block group descriptors reading IO is not sequential and requires optimization. Signed-off-by: Andrew Perepechko --- fs/ext4/super.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/ext4/super.c b/fs/ext4/super.c index a673558..0e52c91 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -3879,6 +3879,12 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) bgl_lock_init(sbi->s_blockgroup_lock); + /* Pre-read the descriptors into the buffer cache */ + for (i = 0; i < db_count; i++) { + block = descriptor_loc(sb, logical_sb_block, i); + sb_breadahead(sb, block); + } + for (i = 0; i < db_count; i++) { block = descriptor_loc(sb, logical_sb_block, i); sbi->s_group_desc[i] = sb_bread_unmovable(sb, block); -- 1.8.3.1