On 01/01/2017 05:38 PM, Andrei Borzenkov wrote:
Which is exact definition of "hot spare". Drive that is used to restore redundancy *automatically*, without involving manual actions. I do not see what magic in btrfs suddenly makes it "meaningless".
+ BIGNUM ! ! Indeed. "Hot Spare" that way pre-dates BtrFS! It pre-dates Linux, it pre-dates the PC, it pre-dates UNIX, it pre-dates the mainframe, it pre-dates digital and analog computers. it probably pre-dates steam engines. I'm pretty sure that if I dig I can find examples of ancient Greek or Roman imaginary (the Romans were good, inventive engineers) that automatically tripped over to a standby if the primary failed. "Mirror standby" is remarkably easy to engineer in many situations. There is a philosophical argument that what causes the failure of the primary may be a design or implement flaw that means the mirror will fail exactly the same way at the same time, and we've touched on that here a few times (e.g. having drives from the same production batch). Savvy engineers usually foresee this possibility and navigate around it. Andrei is right! Whatever advantages BtrFS offers, it does not make simple good engineering practices irrelevant! -- A: Yes. > Q: Are you sure? >> A: Because it reverses the logical flow of conversation. >>> Q: Why is top posting frowned upon? -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org