[linux-lvm] Re: [PATCH] 64 bit scsi read/write

[Alan Cox <alan lxorguk ukuu org uk>]

> 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.

Hohohoho.

> 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

Alan