/dev/gptid/... is causing slow I/O on pool poolz1-1

[elkmaster]

I do have a zpool made from 3 disks. but since yesterday I get

/dev/gptid/[3diferentids]049226d9b384 is causing slow I/O on pool poolz1-1

for all three disks of the pool.
I do some poool transfer in parallel with zfs send/receive but the send receive isnt interrupted just some "save files" with bigger file size.

What can it be ?

scrub and smart says both no errors

 

[sretalla]

What is your hardware... are those disks SMR? https://www.truenas.com/community/resources/list-of-known-smr-drives.141/

 

[elkmaster]

I dont see any indication for ATA ST4000VN008-2DR1 to be a SMR disk. The main price compare portals say this is an CMR HDD

 

[elkmaster]

I think I do see this after reaching around 75% of pool capacity