On 2013-05-12 08:34, Tim Mohlmann wrote:
As for choking the backplane: That would just slow things down a bit, am I right?
A bit, a lot, or not at all -- I think IRL you'll have to test it under your workload and see.
[ WD performance ]
Did not know that. Do you have any references. Does this also apply for the enterprise disks?
Here's one write-up: https://wiki.archlinux.org/index.php/Advanced_Format Have not tested "enterprise" disks.
Another question: do you use desktop or enterprise disks in your cluster? I am having trouble finding a MTBFs for desktop drives. And if I find them, they are almost the same as enterprise drives. Is there a caveat in there? Is the failure test done is different conditions? (Not that you have to know that) If the annual failure rate would be double, it would still be cheaper to use desktop drives in a large cluster, but I just like to know to be sure.
I don't think anyone knows for sure how much of it is marketing bull. One rumour is the difference between "enterprise" and "desktop" drives is very often only the firmware and the price tag. So yeah, we use desktop versions because it's cheaper, but we use them in raids (usually 1/10 - and it's still cheaper), and we don't do super high performance i/o on them. (Our requirements are size rather than speed.)
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