From: Matthew Wilcox <willy@infradead.org>
To: Qu Wenruo <quwenruo.btrfs@gmx.com>
Cc: "linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
linux-btrfs <linux-btrfs@vger.kernel.org>,
"linux-block@vger.kernel.org" <linux-block@vger.kernel.org>
Subject: Re: Why a lot of fses are using bdev's page cache to do super block read/write?
Date: Wed, 9 Jul 2025 13:01:25 +0100 [thread overview]
Message-ID: <aG5aFfflP_OPE_ND@casper.infradead.org> (raw)
In-Reply-To: <5459cd6d-3fdb-4a4e-b5c7-00ef74f17f7d@gmx.com>
On Wed, Jul 09, 2025 at 06:35:00PM +0930, Qu Wenruo wrote:
> This leads more digging, and to my surprise using bdev's page cache to do
> superblock IOs is not an exception, in fact f2fs is doing exactly the same
> thing.
Almost all filesystems use the page cache (sometimes the buffer cache
which amounts to the exact same thing). This is a good thing as many
filesystems put their superblock in the same place, so scanning block
devices to determine what filesystem they have results in less I/O.
next prev parent reply other threads:[~2025-07-09 12:01 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-07-09 9:05 Why a lot of fses are using bdev's page cache to do super block read/write? Qu Wenruo
2025-07-09 12:01 ` Matthew Wilcox [this message]
2025-07-09 15:04 ` Darrick J. Wong
2025-07-09 20:40 ` Qu Wenruo
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