On 27/11/2018 21:27, Havard Eidnes wrote:
Just checked that and the settings are the same. I've also disassembled and re-assembled the machine after the reconstruct completed (after 3 days). The write performance of the real raid is now just as slow with one disk showing 100% busy and the other showing 1% busy in systat vmstat. This was using fresh cables and I also swapped the 2 raid disks around on the motherboard connection. The slow performance followed the disk and didn't stay bound to the port.It could be that the caching settings on the new drive is different from the old one. Check and adjust with "dkctl", using "getcache" and "setcache" as required.
Based on that and the rather more sensible performance of the raid1 set in my other NetBSD 8 system I'm just going to assume the disk is bad and replace it ASAP.
I have just got some 4TB disks to replace the existing 2TB volumes so once I've done a data copy I'll have the opportunity to rede a reconstruct on the new disks.
So for now just assume duff hardware. Sorry for the noise and thanks for the suggestions.
Mike