Storage Spaces won't use all disk space

Question

I have allocated 5 drives (3x 4TB HDD, 2x 8TB HDD) to my storage space and created a simple pool on it. (No redundancy)

While total disk space is 25.4 TB (3.633 + 7.272) and I've allocated all of it to my pool my programs fails to write anything more to the pool.

It says no space is available although there are still approx. 25% disk space left on both of my 8TB drives.

I've already allocated all the space to the pool as you can see in the screenshots. (Well during various attempts it gradually risen to 25.5 because it won't let me shrink the pool size. But I don't think that's the problem here, right?)

"Optimizing drive usage" doesn't do anything. It should move some data from my 4TB drives into 8TB drive thus balancing the usage but it does nothing.

(I've tried this on legacy control panel, new settings page, and also via powershell.)

It used to be able to use up all the drives up to 100% before but this behavior is new to me.

Answer 1

Hello there,

If Storage Spaces is not utilizing all the available disk space, there could be several reasons for this behavior. Here are a few possible causes and troubleshooting steps:

Disk formatting and size reporting: Verify that the disks in your Storage Spaces pool are correctly formatted and reporting their full capacity. Sometimes, the reported size of a disk may be slightly smaller due to the way manufacturers calculate storage capacity. Check the disk properties in Disk Management or using disk management tools to ensure the disks are recognized at their full capacity.

Provisioning type: Check the provisioning type set for your Storage Spaces pool. Storage Spaces offers two provisioning types: "Simple" and "Mirror" or "Parity." Simple provisioning uses all available space immediately, while Mirror and Parity provisioning reserve some space for redundancy and data protection. Ensure that you have selected the appropriate provisioning type based on your requirements.

Reservations and over-provisioning: Storage Spaces may reserve a portion of the available disk space for metadata, system use, or other purposes. This is known as over-provisioning. The amount of reserved space depends on the configuration and settings of your Storage Spaces pool. It is normal for some disk space to be reserved and not immediately available for data storage.

I used AI provided by ChatGPT to formulate part of this response. I have verified that the information is accurate before sharing it with you.

Hope this resolves your Query !!

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Answer 2

I've created a new pool in the same primordial pool and moving files into that pool.

So far new pool is working correctly and my 8TB drives show more than 75% usage.

I think my current pool is somehow corrupted thus resulting in this behavior.

I'll add more info after some time.