Date: Wed, 16 Sep 1998 21:36:40 -0600 (MDT) From: "Kenneth D. Merry" <ken@plutotech.com> To: matt@clintondale.com (Matt Hamilton) Cc: current@FreeBSD.ORG Subject: Re: SCSI spindowns and CAM Message-ID: <199809170336.VAA29729@panzer.plutotech.com> In-Reply-To: <Pine.BSF.3.96.980916222947.9619B-100000@boris.clintondale.com> from Matt Hamilton at "Sep 16, 98 10:35:42 pm"
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Matt Hamilton wrote... > Dear All, > I've been meaning to ask this for a while,a nd I wonder if now anything > has changed with CAM being introduced: Is it possible to spin down SCSI > disks when not in use? Somehow send them a STOP command after a certain > amount of inactivity? Or trigger it from APM or something? My old IDE > disks used to spin down after inactivity via a bios setting, and I seem to > remember FreeBSD had no problems with this. There isn't any code in the kernel to do that at the moment. I would only try to do that on a laptop, though. Stopping and starting drives a lot will probably only wear them out sooner. If you want to manually send a stop command to the drive in question, you can do something like: camcontrol stop -n da -u 0 You could probably even write some code to periodically poll the devstat information for the drive in question and then use camcontrol to spin it down. CAM will automatically spin the drives up again when you try to access them. > For the record my controller is an onboard AIC7880 and I'm running > -current with CAM (aout) > > Also I get this: > > da0 at ahc0 bus 0 target 1 lun 0 > da0: <IBM DFHSS2W 1717> Fixed Direct Access SCSI2 device > da0: 10.0MB/s transfers (10.0MHz, offset 15), Tagged Queueing Enabled > da0: 2150MB (4404489 512 byte sectors: 255H 63S/T 274C) > da1 at ahc0 bus 0 target 2 lun 0 > da1: <IBM DFHSS2W 4G4G> Fixed Direct Access SCSI2 device > da1: 10.0MB/s transfers (10.0MHz, offset 15), Tagged Queueing Enabled > da1: 2150MB (4404489 512 byte sectors: 255H 63S/T 274C) > > Both the drives are WIDE SCSI-II and I thought they are meant to run at > 20MB/s (I have 20Mb/s set in my Adaptec BIOS)? I haven't had them very > long and so I'm not sure if they were indeed running 20MB/s before CAM was > introduced. > > Any insight? Do you have wide negotiation turned on in the Adaptec bios? It could be that they're wide, non-Ultra drives and you just don't have wide negotiation turned on. If you do have wide negotiation turned on in the bios, we'll need to know what sort of motherboard you've got, termination settings in the bios, and so on. Ken -- Kenneth Merry ken@plutotech.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message
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