> If, after a power outage, the IDE disk can keep going for long enough
to write its write cache out to the reserved vendor area (which will
only take 20-30 milliseconds) then the data may be considered *safe*
as soon as it hits writecache.
In which case it is perfectly legitimate and sensible for the drive
to ignore flush commands, and to ack data as soon as it hits cache.
Since the flushing commands are 'optional' it can legitimately ignore them
If I'm right then the only open question is: which disks do and
do not do the right thing when the lights go out.
As far as I can tell none of them at least in the IDE world