Re: True fsync() in Linux (on IDE)

[Christoffer Hall-Frederiksen]

Matthias Andree wrote:
> Jens Axboe schrieb am 2004-03-22:
>
>
> > There's no such thing as atomic writes bigger than a sector really, we
> > just pretend there is. Timing usually makes this true.

;)

> If there is no such atomicity (except maybe in ext3fs data=journal or
> the upcoming reiserfs4 - isn't there?), then nobody should claim so. If
> the kernel cannot 100.00000000% guarantee the write is atomic, claiming
> otherwise is plain fraud and nothing else.
>
> Some people bet their whole business/company and hence a fair deal of
> their belongings on a single data base, and making them believe facts
> that simply aren't reality is dangerous. These people will have very
> little understanding for sloppiness here. Linux has no obligation to be
> fast or reliable, but it MUST PROPERLY AND TRUTHFULLY state what it can
> guarantee and what it cannot guarantee.

Some databases (eg. oracle) can write a checksum for each database page 
to overcome this problem, as this is not just "a linux problem".


--
	Christoffer

	Topper Harley: Interesting perfume.
	Ramada Thompson: It's Vicks. I have a cold.
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