Brian K. White wrote:
----- Original Message ----- From: "Matt Archer"
To: "opensuse" Sent: Wednesday, June 18, 2008 3:22 PM Subject: Re: [opensuse] Computer freezes a lot Carlos E. R. wrote:
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The Wednesday 2008-06-18 at 06:05 -0400, Matt Archer wrote:
Ask your HD manufacturer. Once we asked Seagate about the life expectancy of disks continuously on, or automatically standed down (not spinning). The said: "the same, no effect".
You didn't ask about reduced disk-head movement, and the life span of reducing it by spreading filesystems over more disks. Sleep mode, means no motor, and no head movement. Common sense say they'd last longer that way. Manufacturer says "no".
Well of course-- the motor bearing is generally NOT the point of failure -- the far more fragile read/write arm assembly bearing often is.
It doesn't matter if you spin down the disk if you still do the same amount of disk-head movement per day.
Also, when you spin down the disk, the head touches the platter and suffers friction both while coming to a stop and while starting up.
The whole time the disk is spinning, the head never touches the platter but floats on a film of air.
Also, all electrical circuits suffer a surge when going from off to on, that they don't suffer while merely on, and that surge is worse than some large number of hours or days of contiuous "on", so that is yet another way that spinning up/down produces more wear than merely being on continuously.
Similarly but to an even larger extent, the main motor works a lot harder to spin a drive up than to maintain it's running rpm. That translates to higher current going through various parts of the motor coils and the driver circuit, which means heat and/or chance of burnout of some part.
I can very easily imagine that modern drives will last longer if running continuously for 5 years than if spun down 10 times a day and asleep 8 hours a day for 5 years.
Fans last a lot longer when they are spun down because their bearings are garbage compared to whats inside a disk, the balance of the impeller is garbage compared to a disk platter, and a disk is a sealed pristine environment while a fan bearings are hardly protected at all. That little sticker on the back means nothing, dust gets in though the other side under the impeller quite readily.
Very true. One year in the Iraq/Kuwait desert turned a laptop fan into a real noise-maker -- and that was operating ONLY indoors, and usually with a thick blanket between my legs and the bottom of the laptop (providing some filtering mechanism) primarily because roomies always cranked the A/C as if living in the desert meant that indoors it should be 60F (15C) -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org