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Subject: Re: [PATCH RFC] mm: implement write-behind policy for sequential file
 writes
To: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>,
        linux-fsdevel@vger.kernel.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Cc: Jens Axboe <axboe@kernel.dk>, Michal Hocko <mhocko@suse.com>,
        Mel Gorman <mgorman@suse.de>, Johannes Weiner <hannes@cmpxchg.org>,
        Tejun Heo <tj@kernel.org>, Andrew Morton <akpm@linux-foundation.org>,
        Linus Torvalds <torvalds@linux-foundation.org>
References: <150693809463.587641.5712378065494786263.stgit@buzz>
From: Florian Weimer <fweimer@redhat.com>
Message-ID: <c684ee77-27a6-1522-b443-0c6d33d569a0@redhat.com>
Date: Mon, 2 Oct 2017 13:23:18 +0200
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On 10/02/2017 11:54 AM, Konstantin Khlebnikov wrote:
> This patch implements write-behind policy which tracks sequential writes
> and starts background writeback when have enough dirty pages in a row.

Does this apply to data for files which have never been written to disk 
before?

I think one of the largest benefits of the extensive write-back caching 
in Linux is that the cache is discarded if the file is deleted before it 
is ever written to disk.  (But maybe I'm wrong about this.)

Thanks,
Florian