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Date: Wed, 13 Sep 2006 17:28:49 +0200
From: Teufel <bsd@kuehlbox.de>
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To: Pawel Jakub Dawidek <pjd@FreeBSD.org>,  freebsd-stable@FreeBSD.org
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Subject: Re: gjournal and Softupdates
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Pawel Jakub Dawidek wrote:
>>> - todays desktop drives can lie about writing data. SoftUpdates relies
>>> on some assumptions about when the data is physically written to
>>> media, and those are not always valid today
>>>       
>> I think journaling relies on the same assumptions.
>>     
>
> Not gjournal, because it uses BIO_FLUSH I/O requests which flushes disk
> write cache when needed
so when the crash occur exactly when BIO_FLUSH is sent or while the 
cache is flushing, there is still no corruption possbile?  If so, this 
would be an advantage over SU, as it does surely not use the new 
introduced BIO_FLUSH. In the other hand i've seen couple of other JFS 
that went corrupt for "no reason". I don't want to be paranoid, but i 
really want to be "sure" that the design is trustable.