gjournal and Softupdates

[Daniel O'Connor]

On Tuesday 12 September 2006 19:34, Christian Laursen wrote:
> Ivan Voras <ivoras at 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 
lot of people choke at the performance hit..

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

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

-- 
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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