From: Olaf van der Spek <olafvdspek@gmail.com>
Subject: Re: Atomic non-durable file write API
Date: Mon, 27 Dec 2010 20:07:01 +0100
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Cc: linux-fsdevel <linux-fsdevel@vger.kernel.org>,
	linux-ext4@vger.kernel.org, "Ted Ts'o" <tytso@mit.edu>,
	Nick Piggin <npiggin@gmail.com>
To: Christian Stroetmann <stroetmann@ontolinux.com>
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On Mon, Dec 27, 2010 at 4:30 PM, Christian Stroetmann
<stroetmann@ontolinux.com> wrote:
>> Like I've said dozens of times, this is not about full DB functionality.
>> Why do you keep making false analogies?
>
> The analogy is not so wrong. The concepts atomicity and abort/rollback your
> are talking about are also concepts of the field of database management
> systems (DBMSs). And once you have established the Atomicity, which is the A
> of the principle ACID of DBMSs, you have the basis for establishing the
> rest, the CID.
>
> And you even went further into this DBMS direction by letting down the
> requirement of non-durability.

Of course the concepts are the same. That doesn't mean the analogy is valid.

>> Still waiting on any hint for why that performance loss would happen.
>
> From my point of view, the loss of performance depends on what is
> benchmarked in which way.

Maybe, but still no indication of why.

Olaf