I connected my fourth 12TB WD My Book and started plotting to it overnight, and was horrified to see that phase 4 is suddenly taking more than 40 minutes instead of 10. All drives are connected to the same root hub, but I’m truly hoping 4 drives should not be a problem since I’m planning to connect a lot more than that.
The other 3 disks weren’t doing any writing, only being harvested so I don’t see the problem. Even after killing the harvesters and unmounting all three of them, the IO for the fourth drive is still abysmal.
What could be going wrong here? I formatted it with
mkfs.ext4 -m 0 -T largefile4 just like the others, mounted it the same, and am plotting to it with the same parameters.
Any help would be much appreciated.
OS : Ubuntu Server 21.04
CPU : AMD Ryzen 9 5900X
RAM : 2x 32GB Mushkin Redline Ridgeback G2 3600
MBD : ASUS Prime B550-Plus
SSD : 2x 1.6TB Intel P4610
HDD : 12TB WD My Book over USB3.2
PSU : Corsair HX750
Kind of stumped nobody has experienced this issue before, couldn’t find any threads here or on reddit describing a similarly massive drop in write speed with only this few drives attached.
I’ve been trying to find out what is wrong all day and am no closer than before, and I can’t keep plotting like this. I really need to know if this problem is only going to get worse as more drives get attached, because if that’s the case I might have to pull the plug on chia.
How do I even properly test the write speed of my drives?
hdparm -t only shows read speeds, and I can’t even make sense of those. They’re all over the place for all of my brand new and completely identical 12TB WD My Book drives, all filled with the same number of plots and formatted the exact same way. Most are somewhere around 180MB/s, one is consistently above 200MB/s and another one isn’t even hitting 40MB/s. This is not the drive I’m getting the 40min phase 4 on by the way, even though that is roughly the write speed that would lead to that. It’s the first drive I ever filled, and I had no problems with it at all.
I thought I could get a decent idea of the write speed for each drive by using
rsync and manually performing a phase 4 on a finished plot, but apparently it’s not that easy. Using this method, all of my drives never write faster than 40MB/s.
That is an odd one. Only phase 4 was affected?