How can soft-updates assume a certain write order?

[Loren M. Lang]

How does freebsd gaurentee that meta data is truely written out in the
correct order to ensure data integrity?  Does freebsd specifically wait
for a response to come all the way from the disk drive itself before it
schedules any dependent data to be written?  And if so, is there any
garuntee that any disk controllers, disk drives with their 16 meg
caches, raid controllers or anything else won't change that order in an
attempt to optimize?

Or has the data truely been written to the disk by the time that the
response comes back saying that the data's been written?

-- 
I sense much NT in you.
NT leads to Bluescreen.
Bluescreen leads to downtime.
Downtime leads to suffering.
NT is the path to the darkside.
Powerful Unix is.

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