4 ms·
Sure, you can build striped raidz and 3+ way mirrors and other more exotic variants but the two most typical corners of the configuration space are plain raidz2
by barrkel 4y ago
Sure, you can build striped raidz and 3+ way mirrors and other more exotic variants but the two most typical corners of the configuration space are plain raidz2+ for all the drives vs striped mirrors. You lose usable space not putting all your drives into a single parity array and maximizing usable space is usually why you go with parity. Mixing multiple arrays only makes sense from this perspective if you have a mix of drive sizes.
- eatbitseveryday 4y ago> You lose usable space not putting all your drives into a single parity array Well if you're aiming for a specific ratio but want greater capacity without upgrading all disks to larger capacities, your only option is to use more vdevs configured just the same. Example: 66% usable capacity, 6 disks in a raidz2 (4 usable + 2 parity) or 9 disks in a raidz3 (6 usable + 3 parity). If you want to add capacity but maintain your parity ratio (for a given fault tolerance risk) there is no raidzN with N > 3, so you must add vdev. Increasing the size of the raidz vdev means you're reducing your failure tolerance.