D5-300 Poor Write Speeds

[TentativelyIrritated]

I recently purchased the D5-300, and after a complete nightmare of the raid manager not finding drives and then the created raids never showing up in Disk Manager, I finally managed to get it set up with 5 4TB Seagate Ironwolf NAS drives in a RAID 5 configuration.

When I started to copy things over however, the write speed from an external hard drive to the RAID bottlenecked at 33 MB/s. I thought that might be a limitation of the other drive, so I copied it to an internal SSD then to the RAID. Same issue. I read that RAID 5 is notoriously slower, so I reconfigured to RAID 10 and this time I got between 35 and 40 MB/s.

I've tried different USB ports, I'm currently using Type C to Type C and the write speed remains absurdly slow. Unusably slow. I'm trying to copy 500 GB of large files over, and this isn't acceptable.

That's without mentioning the age and many false starts it takes when booted before the computer or laptop can find it.

Can someone please help me with this?

[whmaurer]

I didn't have any issues with the set up and software, that part was very straightforward for me, but having similar write speed issue here - I set up a D5-300 in RAID 5 with 5 8TB WDC white label drives. According to CrystalDiskMark, the read speeds seem about where I'd expect, but the write speeds are horrendously slow (~260 MB/s read, ~14 MB/s write, see screengrab):

https://imgur.com/a/079220H

I'm running the DAS on my Windows PC to back up about 11TB of data, and it is going to take about a week and a half to complete at this rate. Is this likely a hardware issue, or is there potentially a software/configuration fix in Windows?

[RobertB]

Listen, I really think this is quite normal for RAID 5 write speeds. RAID 5 has a built in redundancy system, like parity or whatnot, so the writes take multiple paths for insurance of resilience. Right?