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Date:   Thu, 27 Sep 2018 09:18:36 +0200
From:   Rogier Wolff <R.E.Wolff@BitWizard.nl>
To:     Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Cc:     "Theodore Y. Ts'o" <tytso@mit.edu>,
        Jeff Layton <jlayton@redhat.com>,
        =?utf-8?B?54Sm5pmT5Yas?= <milestonejxd@gmail.com>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: POSIX violation by writeback error
Message-ID: <20180927071836.GU16802@BitWizard.nl>
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On Wed, Sep 26, 2018 at 07:10:55PM +0100, Alan Cox wrote:
> > And I think that's fine.  The only way we can make any guarantees is
> > if we do what Alan suggested, which is to imply that a read on a dirty
> > page *block* until the the page is successfully written back.  This
> > would destroy performance.
> 
> In almost all cases you don't care so you wouldn't use it. In those cases
> where it might matter it's almost always the case that a reader won't
> consume it before it hits the media.

Wait! Source code builds (*) nowadays are quite fast because
everything happens without hitting the disk. This means my compile has
finished linking the executable by the time the kernel starts thinking
about writing the objects to disk.

	Roger. 

(*) Of projects smaller than the Linux kernel. 

-- 
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