<br><br><div class="gmail_quote">On Fri, Dec 19, 2008 at 12:37 PM, Greg Woods <span dir="ltr"><<a href="mailto:greg@gregandeva.net">greg@gregandeva.net</a>></span> wrote:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div class="Ih2E3d">On Fri, 2008-12-19 at 11:50 -0600, Carl Fongheiser wrote:<br>
<br>
> I think you're tilting at windmills here. At least where I live, it<br>
> costs about 1 cent a day to let a hard drive spin at idle.<br>
<br>
</div>Power cost isn't really the major issue. I'm more worried about drive<br>
lifetime. Even the cost of a new drive isn't the major problem, it's the<br>
major hassle involved in pulling the system out of the rack,<br>
disconnecting and reconnecting all the cables, opening it up, and<br>
replacing a drive, plus losing those recordings. My time to do that is<br>
worth way more than a year of electricity to run a hard drive. I know<br>
that spinning up and down is more stressful per second than just letting<br>
it run, but the truth is that my Myth system is only in use perhaps 4-5<br>
hours a day on average, including recordings (more on weekends when<br>
there are football games, less during the week when the system might be<br>
idle for several days). I have not, as you say, "done the math", but I<br>
have to believe that I'm better off having the drives idle for 19-20<br>
hours a day than having them run all the time. Heat generation is also a<br>
factor, especially in the summer.</blockquote><div><br>You should look at the research done by google on drive failures and see that what you're doing probably isn't helping this at all<br><br><a href="http://research.google.com/archive/disk_failures.pdf">http://research.google.com/archive/disk_failures.pdf</a><br>
<br>They pretty much concluded that temp and activity had very little to do with failure rates. If you're concerned with drive replacement/time/loss, you should consider a RAID 5 option as this will allow you to recover in the event of a single drive failure without data loss and most of the time, without downtime.<br>
<br>Kevin</div></div><br>