When discussing availability of a service, it is common to hear the term “Five Nines” referring to a service being available 99.999% of the time but “Five Nines” are relative.
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In reality, none of those calculations are relevant because no one cares if a service is unavailable for 10 hours, as long as they…

The following table shows the difference between 146GB RAID 5 IOPS/TB and 300GB RAID 10 IOPS/TB.
Each column represents a different Read percentage (the Write percentage is the inverse).
Negative numbers mean that for this Read percentage and IOPS requirement, RAID 10 gives more IOPS/TB of disk. Positive numbers mean that RAID 5 gives better…