SMR Drives compatible with Drivepool ?

[ABorges]

Western Digital has started to use a version of SMR Hard Drives in their Series of WD Red Hard Drives,  long a favorite of home built servers and NAS enthusiasts

https://blog.westerndigital.com/wd-red-nas-drives/

There has been considerable concern about SMR drives  -  especially used in a RAID -  problems during rebuilding specifically

I see some discussion here  in the past on SMR Tech hard drives and Drivepool -    What is the current thinking ?    

My thought is that Drivepool  ,especially with SSD cache enabled, should be more tolerant of drive types ?  -  Correct

[Umfriend]

I can't imagine DP having issues with drive-managed SMR HDDs.

[Christopher (Drashna)]

No issues.  I've been using SMR drives personally since Seagate released the Archive drives.  And I have a pool of mixed drives.  WD Reds, Seagate NAS, Seagate Archive. 

The only caveat is that the SMR drives have a "write cache" of non-SMR space. If you fill that (fairly easy to do so), the write speeds get atrociously slow.   Because of this, I would recommend using the SSD optimizer, to effectively bypass this issue.  Doesn't matter if balancing is slow, since it is  any ways.

In fact, that's the setup that I have (for years now), and it works wonderfully. 

[TomP]

On 4/28/2020 at 2:23 AM, Christopher (Drashna) said:

...I would recommend using the SSD optimizer, to effectively bypass this issue.  Doesn't matter if balancing is slow, since it is  any ways....

Is there a user guide for SSD Optimizer so I can set it up correctly ?

[Christopher (Drashna)]

No, there isn't.  Basically, it's install it, enable it, select the SSD drives, and that's it.  

[Chris Downs]

On 6/3/2020 at 8:54 AM, TomP said:

Is there a user guide for SSD Optimizer so I can set it up correctly ?

It's a bit too simple for a guide... just remember that you need more than one SSD if your pool has duplication. 2x dupe needs 2x SSD, 3x needs 3 etc. Also, keep in mind that the size of the SSDs determine the maximum filesize you can move onto the pool. I once had a pool with some 64GB SSDs as landing drives, and spend a while scratching my head when I couldn't copy across some large disk-image backups despite the pool having plenty of space.