Subject: Re: wd, disk write cache, sync cache, and softdep.
To: Bill Studenmund <>
From: Manuel Bouyer <>
List: tech-kern
Date: 12/18/2004 09:33:43
On Sat, Dec 18, 2004 at 09:07:56AM +0100, Manuel Bouyer wrote:
> The FUA bit should for the media acess, so in this case the cache flush
> for A3, and any commands queued before A3 if A3 is queued with
> ordered queue tag + FUA.

Hum, FUA and simple/ordered tasks are defined in 2 different SCSI drafts
(SCSI block command and SCSI Architecture model), so things are not that
clear. We may need to set the FUA bit on all 3 commands to make sure A1 and A2
reach the platters before A3.

Manuel Bouyer <>
     NetBSD: 26 ans d'experience feront toujours la difference