Windows7ge
Contributor
- Joined
- Sep 26, 2017
- Messages
- 124
VDEV I'm not sure what that is but raidz1/2 (for HDDs at least) does scale well beyond one drive performance with the more you add. My 8 drive raidz2 peaks around 650MB/s writes and 750MB/s readsI'd be interested to see the outcome of that test as I have seen many discussions on a theoretical level cover the fact that a RAID VDEV (RAIDZ1/2 or other types) is only as fast as one of the member devices, hence everybody is saying that a pool of many mirrored VDEVs is the best way to get performance and keep some redundancy.
According to the theory, RAIDZ1/2 should kill over 90% of your potential performance with 12 devices in a single VDEV.
Notably, RAID0 or in FreeNAS terms "stripe" should not be subject to that rule as it is the same as each device in the pool being its own VDEV.
Now an OS that does what you just explained is UnRAID. That's the drawback to being able to throw together just any drives (but you can use an SSD cache so that negates the drawback, also drive failure only costs you the data on that one disk but you can still have parity to negate that, I'm getting off topic...)
Yes RAID0 would just give you ALL the performance but even with a backup array rebuilding the SSD array after drive failure would suck & I couldn't utilize that much throughput even with 20Gbit. 40Gbit couldn't even give me what it'd be capable of so I'd rather build in redundancy.