[Retric]

It depends on what you’re doing and what you’re concerned about.

For a simplified example suppose you have X drives storing 20TB vs 2X drives with 10TB in a simple RAID 1 configuration. When a drive fails there’s a risk period before its contents are replicated on another drive. At constant transfer speeds larger disks double that period per drive but half the number of failures. Net result the risk is identical in both setups.

However, that assumes a constant transfer speeds, faster transfer rates reduce overall risks.

[rcthompson]

Hmm, I hadn't considered that doubling the drive size doubles the resilver time and therefore doubles the exposure time for risk of array loss. I guess the math gets complicated depending on RAID topology.