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From: erik quanstrom <quanstro@quanstro.net>
To: 9fans@9fans.net
Subject: Re: [9fans] 9pfuse and O_APPEND
Date: Fri, 19 Dec 2008 14:31:47 -0500	[thread overview]
Message-ID: <35379d4d7cdfa8ead14c7f029ab15bb7@quanstro.net> (raw)
In-Reply-To: <509071940812191121q7cbd36e4yf6ac6abf04cd84c2@mail.gmail.com>

On Fri Dec 19 14:24:52 EST 2008, anothy@gmail.com wrote:
> > client by definition knows more than the server.
>
> i assume you mean "knows less"? the server knows where EOF is and
> which files to enforce append-only on. your #1 seems to only exist
> because the client doesn't have that info.

i think it's deeper than that.

if the server has instructions to stick the write at the
end of the file, the server has the ability to prevent
any other writes while executing the append.  doing
this at the client side is hard because regardless of the
client's knowledge, there can be other clients which also
believe they know things equally well and without some
sort of locking or other shenagins on the side, there's a race.

the server is almost by definition in a better position
to append than the client.

- erik



  reply	other threads:[~2008-12-19 19:31 UTC|newest]

Thread overview: 33+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-12-18 23:34 Roman Shaposhnik
2008-12-18 23:57 ` Russ Cox
2008-12-19  0:03   ` ron minnich
2008-12-19  3:06     ` Roman Shaposhnik
2008-12-19  3:26       ` ron minnich
2008-12-19  3:59         ` Roman Shaposhnik
2008-12-19 16:44           ` ron minnich
2008-12-19 19:21             ` Anthony Sorace
2008-12-19 19:31               ` erik quanstrom [this message]
2008-12-19 19:41               ` ron minnich
2008-12-19 19:59             ` Roman Shaposhnik
2008-12-19 20:06               ` erik quanstrom
2008-12-19 20:18               ` Charles Forsyth
2008-12-21  5:08                 ` Roman V. Shaposhnik
2008-12-19  3:03   ` Roman Shaposhnik
2008-12-19  3:43     ` erik quanstrom
2008-12-19  3:54       ` Roman Shaposhnik
2008-12-19  4:13         ` geoff
2008-12-19  8:23           ` Russ Cox
2008-12-19 19:49             ` Roman Shaposhnik
2008-12-19 19:56               ` erik quanstrom
2008-12-19 20:10                 ` Roman Shaposhnik
2008-12-19 20:22                   ` erik quanstrom
2008-12-19 20:02               ` ron minnich
2008-12-19 14:21           ` erik quanstrom
2008-12-19 21:00 ` ron minnich
2008-12-19 21:32   ` Charles Forsyth
2008-12-19 21:29     ` ron minnich
2008-12-21  5:05   ` Roman V. Shaposhnik
2008-12-21 14:45     ` erik quanstrom
2008-12-22 10:02       ` roger peppe
2008-12-25  6:04       ` Roman Shaposhnik
2008-12-25  6:33         ` erik quanstrom

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