On: Why are my ZFS disks so noisy?

[Maledictus]

I expected a way to find out what the heck the system is sending to those disks. Like per process and what the the Kernel/ZFS is adding.

[M95D → Maledictus]

It can be done with CONFIG_DM_LOG_WRITES and another set of drives, but AFAIK, it needs to be set up before (or more exactly under) zfs.

[hi-v-rocknroll → Maledictus]

I'd have a look at jobs like scrubbing.

[Sesse__ → Maledictus]

blktrace is fairly useful in this regard.