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From: "Daniel O'Connor" <doconnor@gsoft.com.au>
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Date: Tue, 12 Sep 2006 23:28:35 +0930
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Cc: Christian Laursen <xi@borderworlds.dk>
Subject: Re: gjournal and Softupdates
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On Tuesday 12 September 2006 19:34, Christian Laursen wrote:
> Ivan Voras <ivoras@fer.hr> writes:
> > - 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.

You can disable write caching on your disks (most even honour it :) however=
 a=20
lot of people choke at the performance hit..

One big problem is that high capacity disks use track writing - if you modi=
fy=20
a single sector the disk re-writes the whole track.

If the power fails during the track write then you lose potentially complet=
ely=20
unrelated data. This affects all file systems equally though.

=2D-=20
Daniel O'Connor software and network engineer
for Genesis Software - http://www.gsoft.com.au
"The nice thing about standards is that there
are so many of them to choose from."
  -- Andrew Tanenbaum
GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C

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