I want to adjust storage job priority levels which will speed up storage rebalancing in our S2D cluster.

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Based on the description, it appears that the previously suggested commands are not supported methods for increasing Storage Spaces Direct (S2D) repair or rebalancing speed. That's likely why you did not see the expected behavior when trying them.

In S2D, repair and rebalance operations are managed automatically by the storage subsystem. For Windows Server 2019 and later, the supported method for influencing how much resource is allocated to repair and resync activities is the Storage Repair Speed setting.

You can check the current setting by running:

Get-StorageSubSystem -FriendlyName "<Cluster Name>" |

Select FriendlyName, VirtualDiskRepairQueueDepth

To modify the repair speed, use:

Set-StorageSubSystem -FriendlyName "<Cluster Name>" `

-VirtualDiskRepairQueueDepth <value>

The available values are:

• 1 = Very Low
• 2 = Low
• 4 = Medium (default)
• 8 = High
• 16 = Very High

Higher values allocate more resources to repair and resync operations, which can help restore resiliency more quickly after a disk replacement. However, increasing the repair speed may also affect application and workload performance while the repair is in progress.

If your concern is specifically related to balancing data after replacing or adding drives, you can also manually initiate a pool optimization:

Optimize-StoragePool -FriendlyName "<Pool Name>"

Please note that this operation can be I/O intensive and may temporarily increase storage activity.

For additional information, please visit:

Set-StorageSubSystem (Storage) | Microsoft Learn

Adjust storage repair speed in Azure Local and Windows Server clusters | Microsoft Learn

Optimize-StoragePool (Storage) | Microsoft Learn

Understand and monitor storage resync | Microsoft Learn

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Hello,

By default, Storage Spaces Direct (S2D) relies on background storage jobs that run with low priority to avoid impacting production workloads. These jobs include repair, rebalancing, and scrubbing. When you replace a failed HDD, the cluster automatically triggers a repair job to redistribute data, but the priority is intentionally throttled to minimize performance disruption. That’s why you’re seeing localized high disk utilization during rebuilds-it’s working, but not aggressively enough to finish quickly.

You can adjust this behavior using PowerShell. The relevant cmdlet is Set-StorageSubSystem -ThrottleLimit. For example, running:

Get-StorageSubSystem | Set-StorageSubSystem -ThrottleLimit 100

will increase the throttle limit to 100 percent, effectively allowing repair and rebalancing jobs to consume more I/O and CPU resources. The default is usually 30, which keeps jobs in the background. Raising it speeds up rebalancing significantly, but you must be aware that it can impact live workloads if the cluster is under heavy use.

Another option is to use Set-StorageJob to change the priority of a currently running job. For example:

Get-StorageJob | Set-StorageJob -Priority High

This forces the repair/rebalance job to run at higher priority immediately. It’s particularly useful right after replacing a failed drive when you want the cluster to heal faster.

Best practice is to temporarily raise the throttle or job priority during maintenance windows or after hardware replacement, then return it to default once the cluster is healthy again. This balances recovery speed with workload stability.

I hope you've found something useful here. If it helps you get more insight into the issue, it's appreciated to accept the answer. Should you have more questions, feel free to leave a message. Have a nice day!

HP.