kern/106340: Need to control disk write cache on per-disk basis

[Dieter]

The following reply was made to PR kern/106340; it has been noted by GNATS.

From: Dieter <freebsd at sopwith.solgatos.com>
To: mjacob at freebsd.org
Cc: freebsd-gnats-submit at freebsd.org, freebsd-bugs at freebsd.org
Subject: Re: kern/106340: Need to control disk write cache on per-disk basis 
Date: Mon, 04 Dec 2006 12:27:46 +0000

 In message <20061204104730.H15778 at ns1.feral.com>, mjacob at freebsd.org writes:
 
 > > FreeBSD only allows setting disk write cache mode on a system wide basis,
 > > and only at boot time.  NetBSD allows setting the disk write cache mode
 > > of each disk individually, and does not require a reboot.  See the NetBSD
 > > dkctl(8) man page.
 > 
 > Which disks are you talking about? ATA disks?
 
 Yes, SATA disks. 
 
 > For scsi disks you can do modepage edits via camcontrol that change it 
 > on a per-disk basis, so I assume you must be talking about ATA disks 
 > here, in which case it sounds like a simple addition to atacontrol(8).
 
 I did find camcontrol, but the only drive that shows up in camcontrol devlist
 is the PATA CD/DVD drive.  This system doesn't have any real SCSI drives.