Option to choose how data can be written

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Brief description of the problem

[Disk fillup]

Detailed step by step instructions to reproduce the problem

[I want to know how the disk fillup works on Rockstor. I´m a using Unraid since 5 years and their you have the option how you want your data can be written to the disks. I have monitoring the disks written under pool>poolname and I see its started to write to the largest disk first then to the second largest disk and so on. My question is if theirs´s an option to choose how the data can be written to the disks.]

Web-UI screenshot



Error Traceback provided on the Web-UI

[paste here]

Hi @AndreasG79 welcome to the Rockstor community.

I believer, part of the strategy on how it initially writes to the various disks depends a bit on the RAID set up that you have chosen. What RAID level have you set up your system with?

Part of the imbalance is typically addressed over time when using a scheduled task that performs the balancing to more evenly utilize disk space across the array. I’m not the expert obviously, but I think I also remember that in arrays with different disk sizes the the btrfs strategy will favor the larger disks first (but I don’t have a fact sheet to back that up).

Just as a general comment, whatever btrfs management does comes from upstream, as Rockstor only exposes the functionalities of btrfs (and other components), as opposed to superseding its functionality with something different. And, of course, as btrfs continues to evolve, not all options/features are realized within Rockstor (things like full block device usage, even though other designs are technically possible, etc.).

1 Like

Thank you for the information. I have for now various disk size just for testing out Rockstor to see if it is good for my needs. I will make another test when my 2 new 12TB HDD arrives then I will replace my 4 2TB HDD. Thanks again for your help.
Best regards!