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Re: Safe File Update (atomic)

> Getting people to believe that you can't square a circle[1] 
> is very hard, 

Just allow an infinite number of steps and it's almost trivial ;-)

> It's like trying teaching a pig to sing. 

Well, that works, just sounds a bit like vogon poetry ;-o

> If you give me a specific approach, I can tell you why it won't work,
> or why it won't be accepted by the kernel maintainers (for example,
> because it involves pouring far too much complexity into the kernel).

To come back to the original question, I'd like to know which concrete
realworld problems should be solved by that. One thing an database-like
transactional filesystem (w/ MVCC) would be nice is package managers: 
we still have the problem that within the update process there may be
inconsistent states (yes, this had already bitten me!) - if it would
be possible to make an update visible atomically, that would be a 
big win for critical 24/7 systems.

My approach to this would be an special unionfs with transactional
semantics (I admit: no idea how complex it would be implementing this)

 Enrico Weigelt, metux IT service -- http://www.metux.de/

 phone:  +49 36207 519931  email: weigelt@metux.de
 mobile: +49 151 27565287  icq:   210169427         skype: nekrad666
 Embedded-Linux / Portierung / Opensource-QM / Verteilte Systeme

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