Is putting the hard disks to sleep when possible a good idea?

What OS is on the Wen Server?

I'm not sure anybody knows for sure, but from my experience if the heat in the Drive bay isn't oner 115°F, then spining down/up more than once a day likely shortens their lives.

The newer the version of OSX, the more it beats the drives, imo.

Get Temperature Monitor to check the temps...

http://www.macupdate.com/info.php/id/12381/temperature-monitor

And/or iStat Pro...

http://www.islayer.com/apps/istatpro/

In my own humble (or otherwise) opinion, the power use in a modern hard drive is so minimal that spinning it down does not make sense. It's almost like dimming three LEDs in effect. On the other hand, spinning any motor up to 7200 RPM repeatedly is not doing that motor and its associated circuitry any good.

The energy required to do that does find its way into heat for the mechanism as a whole and stresses other components, like the controller in the drive. It's been maybe 34-35 years since I was in a rotating machinery lab, but I do have vivid memory of starting versus running current and the ratio is pretty high.

I've never considered checking the "let the drives spin down" box; equilibrium state is a good thing in almost any system you could encounter.

Look at this link. http://www.thexlab.com/faqs/harddrivesleep.html

 Cheers, Tom 😉

old comm guy wrote:

The energy required to do that does find its way into heat for the mechanism as a whole and stresses other components, like the controller in the drive. It's been maybe 34-35 years since I was in a rotating machinery lab, but I do have vivid memory of starting versus running current and the ratio is pretty high.

As I recall, the inrush current for induction motors of fractional horsepower size is 10 times or more that of the normal running current.

Don Archibald wrote:

As I recall, the inrush current for induction motors of fractional horsepower size is 10 times or more that of the normal running current.

I would offer that as a lower bound, for sure.

I just looked at the OEM spec for the Hitachi Deskstars I am running right now, and the difference between idle and low RPM idle is 3 watts. One KWH every 13-7/8 days of continuous operation, minus the extra energy consumed in the multiple spin ups. At my usage, that's about $15 a year, cheap insurance to keep the drives happy.

Actually, that's a pretty good number for larger motors, though some of them might double or triple that ratio pretty easily depending on how they are loaded. I noticed on an "open house" at my alma mater a few years ago that they were using very small motors in the lab, as opposed to the seven and 10 HP motors we were using. Cheaper and maybe a little less dangerous. I won't tell the story that scared the stuffing out of a class of EEs one time, except that we definitely learned the meaning of starting torque in a very dramatic fashion.

Its never a good idea to let a hard drive constantly spin up and down, its the primary reason WD's "Green" drives have such an extremely poor lifespan compared to their "blue".

If you're worried about power consumption, skip eating out one night. That money saved will cover more than a decade of a hard drive running.

The worst enemy of a HD is heat, but not only for the obvious reason: When a HD is running all the time the plates (metal) will have a tendency of expanding. Today's controlers can tolerate those minuite changes, but after a few years it will expand quite a bit (talking about microns here). When you turn off that "always spining drive", there's a strong change that metal contration (after cooling down) will prevent the heads from reading due to misalignment and cause errors at boot time, thus rendering the HD unreadable. This is one of the worst IT nightmare for restarting servers after a long shutdown! 😐

Keep them running. Shutting down the drives when not in use is only useful for laptops saving battery life. In a desktop it adds a second of lag waiting to restart it and the electrical savings is minimal.

Your G5 has an actively controlled fan directly blowing on the drives, heat is not an issue.

Agreed. In my 25 years of experience with computers and hard drives, I've found that drives last longest if they rarely are allowed to spin-down. The systems that are powered off nightly or otherwise have the drives spinning up/down all the time tend to go through drives at the rate of one every 3-4 years. The systems that are up and running 24/7 with the drives powered the entire time tend to last 5-7 years and sometimes longer.

If you have a laptop, then that's different. You need to maximize your battery, so powering down whenever possible is a good thing. But for a desktop or server system, no. Disable all power management for the hard drive. And avoid using "green" drives that will power themselves down independently of your operating system's commands.

Dunestrider wrote:

On my personal computers, I've always chose the option to "Put the hard disk(s) to sleep when possible".

But is that really a good idea? Sure, it saves energy,

Even that is questionable, it takes far more power to spin up a drive from standstill than it does to keep it revolving, If it stops and starts a lot you will use extra power as well as cause extra stress on the drive.

Overall it's about as sensible as driving your car by continually accelerating to full speed and then stopping again. Unless the gaps between the two are lengthy.