Hello, @novaspirit , and everyone,
I really liked your recent Youtube video:
…and I’m trying to get a sense of how stably those JMS561 controllers perform in the current Raspbian. Can you please tell us the firmware version for those controllers, shown by a command, such as:
sudo JMS561FwUpdate -d /dev/sda -v
(maybe /dev/md0 instead of /dev/sda)?
I would also really appreciate seeing a further Youtube video which does some torture testing on that NAS, to check how stably that RAID runs under pressure (without any disk controller-related kernel errors or freezes).
I also have a further question. You chose to format your /dev/md0 as ext4. And you got a very decent 90-100 MB/sec through SMB, using the GbE of the Raspberry Pi 4. But what if you decided to use BTRFS, not ext4? Yes, I know BTRFS has built-in RAID, and that would be the normal and tempting thing to use, but BTRFS is not really trusted at present to be used in RAID 5 with this built-in RAID. But NAS appliances out there (such as Synology’s) use BTRFS with RAID5, just not using the built-in RAID which comes with BTRFS.
Can you please tell us what kind of disk performance (same SMB file sharing test) you get with BTRFS, when you format that same /dev/md0 using a command like:
sudo mkfs.btrfs -d single -m single /dev/md0