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Date:   Wed, 2 Mar 2022 12:43:32 -0800
From:   Luis Chamberlain <mcgrof@kernel.org>
To:     "hch@infradead.org" <hch@infradead.org>
Cc:     Kanchan Joshi <joshiiitr@gmail.com>,
        Damien Le Moal <Damien.LeMoal@wdc.com>,
        Jens Axboe <axboe@kernel.dk>,
        Pavel Begunkov <asml.silence@gmail.com>,
        Kanchan Joshi <joshi.k@samsung.com>,
        "viro@zeniv.linux.org.uk" <viro@zeniv.linux.org.uk>,
        "bcrl@kvack.org" <bcrl@kvack.org>,
        Matthew Wilcox <willy@infradead.org>,
        "linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-aio@kvack.org" <linux-aio@kvack.org>,
        "io-uring@vger.kernel.org" <io-uring@vger.kernel.org>,
        "linux-block@vger.kernel.org" <linux-block@vger.kernel.org>,
        "linux-api@vger.kernel.org" <linux-api@vger.kernel.org>,
        SelvaKumar S <selvakuma.s1@samsung.com>,
        Nitesh Shetty <nj.shetty@samsung.com>,
        Javier Gonzalez <javier.gonz@samsung.com>,
        Johannes Thumshirn <Johannes.Thumshirn@wdc.com>,
        Naohiro Aota <Naohiro.Aota@wdc.com>,
        Adam Manzanares <a.manzanares@samsung.com>,
        "Remzi H. Arpaci-Dusseau" <remzi@cs.wisc.edu>
Subject: Re: [PATCH v4 6/6] io_uring: add support for zone-append
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On Tue, Sep 08, 2020 at 04:18:01PM +0100, hch@infradead.org wrote:
> On Mon, Sep 07, 2020 at 12:31:42PM +0530, Kanchan Joshi wrote:
> > But there are use-cases which benefit from supporting zone-append on
> > raw block-dev path.
> > Certain user-space log-structured/cow FS/DB will use the device that
> > way. Aerospike is one example.
> > Pass-through is synchronous, and we lose the ability to use io-uring.
> 
> So use zonefs, which is designed exactly for that use case.

Using zonefs to test append alone can introduce a slight overhead with
the VFS if we want to do something such as just testing any hot path
with append and the block layer. If we want to live with that, that's
fine!

Just saying.

  Luis