From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from dggsgout12.his.huawei.com (dggsgout12.his.huawei.com [45.249.212.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7111E7485; Mon, 24 Feb 2025 01:59:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740362393; cv=none; b=WlBrGcCi8fQksRRTIMNu8DNCNCgrLtXn8p2OeDYs/ZHwFYKRhR6riuK7fEz7WGvTtS5Rq7lXF8kYIwLxoSzSquTSVlbx8cWxyMW26LiHhT0BRDKCYgAqiCdf/D6tFE7w0RLN+ML9ztNiKfG1vWqltbvMKWYCzBihkXoBKFsTS6Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740362393; c=relaxed/simple; bh=fKrszG9NHCY6e29PEfyo0QFYgGgQ/ryEJE73agr7ors=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=YbNpcSXuivyNjkAwnm7xT+y7fsvvw3TdFBUbWa9K4stm3HCkIshA+aYOq/26Cb/yINeMglhJb1CKFYdH8ZKVV6cxyL0b4CzVBfth7MlOGzl9g94fM50CieoErxSAFUbYOtOXhxNsPzSJxTcHMGyj9FVlgewFuWIy5XI44P1yAhg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.235]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4Z1P6t4Lykz4f3js1; Mon, 24 Feb 2025 09:59:18 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.128]) by mail.maildlp.com (Postfix) with ESMTP id 5D43E1A06D7; Mon, 24 Feb 2025 09:59:40 +0800 (CST) Received: from [10.174.179.80] (unknown [10.174.179.80]) by APP4 (Coremail) with SMTP id gCh0CgBXul6K0rtnie_kEg--.41699S3; Mon, 24 Feb 2025 09:59:40 +0800 (CST) Message-ID: <18453da2-35f1-4f65-b84e-d62a89ff3bab@huaweicloud.com> Date: Mon, 24 Feb 2025 09:59:38 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] ext4: Modify the comment about mb_optimize_scan To: Zizhi Wo Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-ext4@vger.kernel.org, jack@suse.com, tytso@mit.edu, yangerkun@huawei.com References: <20250224012005.689549-1-wozizhi@huawei.com> Content-Language: en-US From: Zhang Yi In-Reply-To: <20250224012005.689549-1-wozizhi@huawei.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-CM-TRANSID:gCh0CgBXul6K0rtnie_kEg--.41699S3 X-Coremail-Antispam: 1UD129KBjvJXoW7Cr1rtFy7uF13JFy5ur1kuFg_yoW8Zr4rp3 9xCF18GF1rWr45Cw47Wa4ku3WYqws7Gw48XF1Yvw1Y9FZrCFZ2yasFyw18uFyUArZ5Za45 XFnFgFn5C3Z093DanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUylb4IE77IF4wAFF20E14v26r4j6ryUM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rwA2F7IY1VAKz4 vEj48ve4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_Ar0_tr1l84ACjcxK6xIIjxv20xvEc7Cj xVAFwI0_Gr1j6F4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x 0267AKxVW0oVCq3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG 6I80ewAv7VC0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFV Cjc4AY6r1j6r4UM4x0Y48IcVAKI48JMxkF7I0En4kS14v26r126r1DMxAIw28IcxkI7VAK I48JMxC20s026xCaFVCjc4AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7 xvwVAFwI0_JrI_JrWlx4CE17CEb7AF67AKxVWUAVWUtwCIc40Y0x0EwIxGrwCI42IY6xII jxv20xvE14v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY1x0267AKxVWUJVW8JwCI42IY6xAIw2 0EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x02 67AKxVWUJVW8JbIYCTnIWIevJa73UjIFyTuYvjxUwxhLUUUUU X-CM-SenderInfo: d1lo6xhdqjqx5xdzvxpfor3voofrz/ On 2025/2/24 9:20, Zizhi Wo wrote: > Commit 196e402adf2e ("ext4: improve cr 0 / cr 1 group scanning") introduces > the sysfs control interface "mb_max_linear_groups" to address the problem > that rotational devices performance degrades when the "mb_optimize_scan" > feature is enabled, which may result in distant block group allocation. > > However, the name of the interface was incorrect in the comment to the > ext4/mballoc.c file, and this patch fixes it, without further changes. > > Signed-off-by: Zizhi Wo Looks good to me. Reviewed-by: Zhang Yi > --- > fs/ext4/mballoc.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c > index b25a27c86696..68b54afc78c7 100644 > --- a/fs/ext4/mballoc.c > +++ b/fs/ext4/mballoc.c > @@ -187,7 +187,7 @@ > * /sys/fs/ext4//mb_min_to_scan > * /sys/fs/ext4//mb_max_to_scan > * /sys/fs/ext4//mb_order2_req > - * /sys/fs/ext4//mb_linear_limit > + * /sys/fs/ext4//mb_max_linear_groups > * > * The regular allocator uses buddy scan only if the request len is power of > * 2 blocks and the order of allocation is >= sbi->s_mb_order2_reqs. The > @@ -209,7 +209,7 @@ > * get traversed linearly. That may result in subsequent allocations being not > * close to each other. And so, the underlying device may get filled up in a > * non-linear fashion. While that may not matter on non-rotational devices, for > - * rotational devices that may result in higher seek times. "mb_linear_limit" > + * rotational devices that may result in higher seek times. "mb_max_linear_groups" > * tells mballoc how many groups mballoc should search linearly before > * performing consulting above data structures for more efficient lookups. For > * non rotational devices, this value defaults to 0 and for rotational devices