Review Azure Files provisioned capacity and snapshot storage
On this page
Azure Files provisioned shares bill for provisioned storage and, depending on the model, provisioned IOPS and throughput regardless of use. Check each share's utilization and snapshot storage before reviewing capacity, or you may miss unused capacity or reduce performance resources the workload needs.
What you need first
- Tool
- Azure Monitor Metrics Explorer is the Azure portal tool for viewing Azure Storage metrics. Start at the storage account, choose Monitoring > Metrics, then select File under Metric namespace.
- Access
- If you cannot view the metrics, ask an authorized Azure storage colleague for the read-only results for the selected storage account, provisioned share, and review window.
- If you do not use that tool
- Send the colleague the subscription, storage account, share name, billing model, and start/end times. Request share-filtered utilization, snapshot size and count, bandwidth and IOPS utilization, displayed aggregations, and billing-model confirmation.
Why this is worth a look
Skipping this review can leave provisioned storage, IOPS, or throughput billed regardless of actual use. In provisioned v2, these resources are separately provisioned and billed based on what you provision. In provisioned v1, provisioned storage determines IOPS and throughput, so reducing storage can reduce performance capacity.
Snapshot count does not show snapshot storage use. Snapshots are incremental and billed for changed content. Review snapshot size separately because snapshots do not count toward the maximum share size limit.
Run this check
CHECKLISTUse these read-only Azure Monitor Metrics Explorer steps for one classic provisioned share. Record identical start and end times, share scope, units, and displayed aggregations for each metric.
1. Record the subscription, storage account, share name, and billing model with the share owner. Confirm this is a classic SMB or NFS share under the Microsoft.Storage resource provider, not a Microsoft.FileShares resource.
2. In the Azure portal, open the storage account. Select Monitoring > Metrics, then File under Metric namespace. Azure Files metrics use the Microsoft.Storage/storageAccounts/fileServices resource type.
3. Choose a review window with explicit start and end times. For metrics supporting the File Share dimension, filter to the target share. If you cannot isolate that share, stop the share-level assessment rather than using account totals.
4. Read Percentage File Share Utilization for the selected share. Record the percentage and displayed aggregation. It is used storage divided by provisioned share capacity, expressed as a percentage.
5. Read File Share Snapshot Size and File Share Snapshot Count with the same share filter and time window. Record bytes for snapshot size and count for snapshot count. Do not treat count as storage size.
6. Read Percentage File Share IOPS Utilization and Percentage File Share Bandwidth Utilization with the same scope and time window. Record the percentages and displayed aggregations for the capacity discussion.
7. Keep UsedCapacity out of the share comparison. It measures storage-account usage and, for standard accounts, includes blob, table, file, and queue capacity.
8. Give the results to the share owner for a capacity and performance review. Record any snapshot-retention question separately. Do not change provisioned resources or delete snapshots during this review.How to confirm it
- 01
Confirm the share and billing model
Ask the share owner to confirm that the target is a classic SMB or NFS share under Microsoft.Storage and uses provisioned v1 or v2. Record the model because provisioned v2 separately provisions storage, IOPS, and throughput, while provisioned v1 derives IOPS and throughput from storage.
- 02
Collect comparable metrics
Run the read-only steps for one share and one recorded time window. Filter metrics by File Share where supported. Stop if the share cannot be isolated, because account-level UsedCapacity cannot establish one share's utilization.
- 03
Review capacity with performance needs
Compare storage utilization with IOPS and bandwidth utilization alongside the owner. Flag low storage utilization for review, not an automatic reduction. In provisioned v1, changing provisioned storage changes the performance resources it determines.
- 04
Review snapshot storage separately
Use snapshot size in bytes, rather than snapshot count, to start a retention discussion with the owner. Keep this separate from the provisioned-capacity decision because snapshots do not count toward the maximum share size limit.
Before making changes
This metric review is not an invoice and does not prove that capacity can safely be reduced. Assume the owner confirms the billing model, share filter, time window, and displayed aggregations suit the workload review. Snapshot size is bytes, snapshot count is a count, and utilization is percent. For reservations, pay-as-you-go snapshot differentials use the normal used-storage meter, while provisioned v1 snapshots use a separate meter outside the reservation.