have to wait for disk to spin up - why?

Doug Lassiter · 12-23-2012, 12:34 PM

I have a LaCie Quadra d2 attached to my iMac (10.6.8) as a backup disk. I do scheduled backups early each morning (SuperDuper). The disk, of course, spins down when it's not being used.

Often when I want to open up a document on my boot disk (e.g. Office) and I pull down to "Open", I have to wait for the backup disk to spin up before I can select my target file (which is NEVER on the backup disk). Why? It's a bit annoying having to wait for that disk to spin up, when that backup disk is irrelevant to the operation I'm trying to perform. OK, I just have to wait five seconds or so, but it's still peculiar.

It doesn't do that every time, and I haven't puzzled out the systematics. Not even sure if this is a system issue or an application issue.

DeltaMac · 12-23-2012, 12:50 PM

Seems like your system (or the app) is simply polling the directory, sees that device mounted, and orders the spinup, perhaps to provide access if a save to some other part of the directory is called (even you wouldn't do a manual save to your backup disk) just to keep it actively available for use.
So, your situation is that the disk, even though it's "spun-down", is still mounted.
If you don't need access to that disk, except for your once-a-day backups, then one easy fix is to unmount the disk, and disconnect.

Doug Lassiter · 12-23-2012, 01:09 PM

Seems like unmounting the disk and remounting it every day would be far more annoying. Although yes, I guess I could do up a script that automatically mounts the volume just for the scheduled backup.

Not clear why an application should, by default, want to have all mounted volumes available when any file is being saved. That is, if I want to open, or save to a despun disk then sure, spin it up!

I'm just not sure I understand what the advantage to the system is, of spinning up disks to enable volumes that aren't being requested.

DeltaMac · 12-23-2012, 01:37 PM

I think the idea, as I see it, is that your system makes your whole file system directory available, even though you only need some small part of it. The system can't read your mind, so activates the directory, even for drives that are spun down. Then you get to wait for those few moments until all parts to become active.
Is this something you have only recently noticed, and your system has operated some other way in the past?
You could go into System Preferences, and turn off "Put hard disk to sleep when possible" in the Energy Saver pref pane. Some manufacturer's have a different setup on their external drives, so that might not affect your LaCie, idk.

NaOH · 12-23-2012, 01:43 PM

Quote:

Originally Posted by Doug Lassiter


	Although yes, I guess I could do up a script that automatically mounts the volume just for the scheduled backup.

If you need a script, something like this will work. I use it for the same purposes as you describe with Keyboard Maestro, but you could simply have iCal/Calendar use it with a repeating event.

Code:

set theDisk to "InsertDiskNameHere"
do shell script "diskutil mount `diskutil list | awk '/ " & theDisk & " / {print $NF}'`"

An unmount script shouldn't be necessary since SuperDuper can handle that when a scheduled backup is completed.

Doug Lassiter · 12-23-2012, 02:03 PM

Thanks for all of this.

In the meantime, I've discovered this ...

http://tntluoma.com/shell-scripts/su...mount-unmount/

which looks to be exactly what I want. I found my self wondering why SuperDuper can't be set up mount or unmount the disk it's cloning to. It can! That is, SuperDuper is smart enough to offer to execute scripts before and after the clone job. You just have to have the right scripts on hand.

acme.mail.order · 12-23-2012, 06:49 PM

Before you go that route, consider that spinup causes most of the wear & tear on a drive. Once it's running it's generally considered that drives have nearly zero wear. So unless you are running the LaCie's on a battery....

anthlover · 12-24-2012, 12:47 PM

And of course the issue your concerned about the latency, you can turn off the disk spin down from Energy Saver settings, I believe the Lacie drives respect that control.

Doug Lassiter · 12-25-2012, 07:34 PM

As a result of a current discussion on the SuperDuper forum site, I see that SuperDuper does in fact do mounts and dismounts automatically. So the simple answer is to keep my backup disk dismounted, such that applications won't want to poll them. If I want to pull something off a backup disk, I just go in there and mount it. That was easy!

Still not quite sure why the applications want to spin up a mounted disk. True, they don't know what I want to do, but I guess the assumption is that if you have a disk mounted, you must want to poll it.

12-23-2012, 12:34 PM	#1
Doug Lassiter Major Leaguer Join Date: Apr 2004 Location: Burnett, Texas Posts: 289	have to wait for disk to spin up - why? I have a LaCie Quadra d2 attached to my iMac (10.6.8) as a backup disk. I do scheduled backups early each morning (SuperDuper). The disk, of course, spins down when it's not being used. Often when I want to open up a document on my boot disk (e.g. Office) and I pull down to "Open", I have to wait for the backup disk to spin up before I can select my target file (which is NEVER on the backup disk). Why? It's a bit annoying having to wait for that disk to spin up, when that backup disk is irrelevant to the operation I'm trying to perform. OK, I just have to wait five seconds or so, but it's still peculiar. It doesn't do that every time, and I haven't puzzled out the systematics. Not even sure if this is a system issue or an application issue.

12-24-2012, 12:47 PM	#8
anthlover Hall of Famer Join Date: Apr 2003 Posts: 2,670	Yup And of course the issue your concerned about the latency, you can turn off the disk spin down from Energy Saver settings, I believe the Lacie drives respect that control.

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12-23-2012, 12:50 PM	#2
DeltaMac League Commissioner Join Date: Jan 2002 Posts: 7,958	Seems like your system (or the app) is simply polling the directory, sees that device mounted, and orders the spinup, perhaps to provide access if a save to some other part of the directory is called (even you wouldn't do a manual save to your backup disk) just to keep it actively available for use. So, your situation is that the disk, even though it's "spun-down", is still mounted. If you don't need access to that disk, except for your once-a-day backups, then one easy fix is to unmount the disk, and disconnect.

12-23-2012, 01:09 PM	#3
Doug Lassiter Major Leaguer Join Date: Apr 2004 Location: Burnett, Texas Posts: 289	Seems like unmounting the disk and remounting it every day would be far more annoying. Although yes, I guess I could do up a script that automatically mounts the volume just for the scheduled backup. Not clear why an application should, by default, want to have all mounted volumes available when any file is being saved. That is, if I want to open, or save to a despun disk then sure, spin it up! I'm just not sure I understand what the advantage to the system is, of spinning up disks to enable volumes that aren't being requested.

12-23-2012, 01:37 PM	#4
DeltaMac League Commissioner Join Date: Jan 2002 Posts: 7,958	I think the idea, as I see it, is that your system makes your whole file system directory available, even though you only need some small part of it. The system can't read your mind, so activates the directory, even for drives that are spun down. Then you get to wait for those few moments until all parts to become active. Is this something you have only recently noticed, and your system has operated some other way in the past? You could go into System Preferences, and turn off "Put hard disk to sleep when possible" in the Energy Saver pref pane. Some manufacturer's have a different setup on their external drives, so that might not affect your LaCie, idk.

12-23-2012, 02:03 PM	#6
Doug Lassiter Major Leaguer Join Date: Apr 2004 Location: Burnett, Texas Posts: 289	Thanks for all of this. In the meantime, I've discovered this ... http://tntluoma.com/shell-scripts/su...mount-unmount/ which looks to be exactly what I want. I found my self wondering why SuperDuper can't be set up mount or unmount the disk it's cloning to. It can! That is, SuperDuper is smart enough to offer to execute scripts before and after the clone job. You just have to have the right scripts on hand.

12-23-2012, 06:49 PM	#7
acme.mail.order League Commissioner Join Date: Sep 2003 Location: Tokyo Posts: 6,046	Before you go that route, consider that spinup causes most of the wear & tear on a drive. Once it's running it's generally considered that drives have nearly zero wear. So unless you are running the LaCie's on a battery....

12-25-2012, 07:34 PM	#9
Doug Lassiter Major Leaguer Join Date: Apr 2004 Location: Burnett, Texas Posts: 289	As a result of a current discussion on the SuperDuper forum site, I see that SuperDuper does in fact do mounts and dismounts automatically. So the simple answer is to keep my backup disk dismounted, such that applications won't want to poll them. If I want to pull something off a backup disk, I just go in there and mount it. That was easy! Still not quite sure why the applications want to spin up a mounted disk. True, they don't know what I want to do, but I guess the assumption is that if you have a disk mounted, you must want to poll it.