Message-ID: <1424964150.13431.57.camel@willson.usersys.redhat.com>
Subject: Re: File Read Returns Non-existent Null Bytes
From: Simo Sorce <simo@redhat.com>
To: Chris Perl <cperl@janestreet.com>
Cc: Trond Myklebust <trond.myklebust@primarydata.com>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>,
        Chris Perl <chris.perl@gmail.com>
Date: Thu, 26 Feb 2015 10:22:30 -0500
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On Thu, 2015-02-26 at 09:10 -0500, Chris Perl wrote:
> > However if you are asking us for an extensive list of "this is what I
> > can expect if I ignore these rules", then I don't think you will find
> > much traction. Such a list would be committing us to defining a model
> > for "non-close-to-open" semantics, which isn't of interest to me at
> > least, and I doubt anyone else is interested in committing to
> > maintaining that.
> 
> One more point on this.  I wasn't really asking for a list of what I
> can expect if I ignore the rules (although I think pointing out that
> reading corrupt data from the cache is worth mentioning), I was asking
> what the rules for close-to-open consistency were so I can follow
> them.  I now know one of them is that if a file is open for writing on
> one client then it can't be read on another.  Are there others?

Is this a rule or a bug ?
How does an application know that the file is open elsewhere for
writing ?

Simo.

-- 
Simo Sorce * Red Hat, Inc * New York