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Date: Tue, 28 May 2024 12:09:02 +0100
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Subject: Re: [LSF/MM/BPF TOPIC] untorn buffered writes
To: Christoph Hellwig <hch@infradead.org>
Cc: Theodore Ts'o <tytso@mit.edu>, lsf-pc@lists.linux-foundation.org,
        linux-fsdevel@vger.kernel.org, linux-mm <linux-mm@kvack.org>,
        Luis Chamberlain <mcgrof@kernel.org>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        Matthew Wilcox <willy@infradead.org>,
        Dave Chinner <david@fromorbit.com>, linux-kernel@vger.kernel.org
References: <20240228061257.GA106651@mit.edu>
 <9e230104-4fb8-44f1-ae5a-a940f69b8d45@oracle.com>
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From: John Garry <john.g.garry@oracle.com>
Organization: Oracle Corporation
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On 28/05/2024 11:57, Christoph Hellwig wrote:
> On Tue, May 28, 2024 at 10:21:15AM +0100, John Garry wrote:
>> If so, I am not sure if a mmap interface would work for DB usecase, like
>> PostgreSQL. I can ask.
> Databases really should be using direct I/O for various reasons.  And if
> Postgres still isn't doing that we shouldn't work around that in the
> kernel.

As I understand, direct IO support for that DB is a work-in-progress, 
but if and ever it is completed I don't know.

Regardless, my plan is to work towards direct IO kernel support now.