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SubjectRe: [POT] Which journalised filesystem ?
> > We (as in Linux) should make sure that we explicitly tell the disk when
> > we need it to flush its disk buffers. We don't do that right, and
> > because of _our_ problems some people claim that writeback caching is
> > evil and bad.
> Does this even work right for IDE ?

Current IDE drives it may be a NOP. Worse than that it would totally ruin
high end raid performance. We need to pass write barriers. A good i2o card
might have 256Mb of writeback cache that we want to avoid flushing - because
it is battery backed and can be ordered.

By all means have drivers fall back to cache writeback, but don't assume
that is the basic operation.

Indeed a smarter raid card can generally do

"read with readahead"
"read with readahead and some readahead on card only"
"read but dont cache"

"write to cache"
"write through cache"
"write uncached"

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