Storage Systems Capacity report

Shows a chart of the 20 storage systems with the most used space, and a table with details of all storage systems. Use the report to review the space allocation in your storage systems.

Charts

The bar chart shows the used space and available space for pools on storage systems.

Report output

Note: IBM FlashSystem® A9000 and A9000R storage systems are not supported by IBM Spectrum Control for this report.

For each storage system, the following information is provided:

Storage System Name
A user-defined name of the storage system. If a name was not defined, IBM Spectrum Control shows the name that was defined when the storage system was added for monitoring.
Storage System Configuration
Shows whether a storage system is configured as back-end storage or configured to virtualize back-end storage. If this value is Storage System, the storage system is configured as back-end storage. If this value is Storage Virtualizer, the storage system is configured to virtualize back-end storage.
Storage System Type
The type of storage system. For example, the storage system can be an IBM System Storage DS8800 system, an IBM System Storage DS8700 system, an IBM System Storage XIV system, or another type of storage system.
Storage System Location
The physical location of a storage system. The location is defined when a storage system is added to IBM Spectrum Control. You can add or edit the location of the storage system in the Properties pane of the storage system.
Storage System Pool Capacity (GiB)
The amount of storage space in pools that are on the storage system. For an XIV or IBM Storage Accelerate, this value represents the physical capacity of the pool, not the virtual capacity. For other storage systems, this value might also include overhead space if the pool is unformatted.
Storage System Used Pool Space (GiB)
The amount of space that is in use in all pools on a storage system.
Storage System Pool Available Space (GiB)
The amount of unused space that is not reserved for volumes in pools that are on the storage system.
Storage System Physical Allocation Percentage
The percentage of physical space in storage system pools that is reserved for volumes. This value is always less than or equal to 100% because you cannot reserve more physical space than is available in the pools.
IBM Spectrum Control uses the following formula to determine this percentage: 
(allocated pool space ÷ pool capacity) × 100
For example, the physical allocation percentage is 25% for a 200 GiB storage pool. Therefore, the space that is reserved for volumes is 50 GiB.
Storage System Virtual Allocation Percentage
The percentage of physical space in storage system pools that is committed to the total virtual capacity of the volumes in the pool. In thin-provisioned environments, this percentage exceeds 100% if a pool is overcommitted (over-provisioned).
IBM Spectrum Control uses the following formula to determine this percentage: 
(total volume capacity ÷ pool capacity) × 100
For example, for a total pool size of 15 GiB, the allocation percentage might be 200%. Therefore, the virtual capacity that is committed to the volumes in the pools is 30 GiB. This configuration means that twice as much space is committed than is physically contained in the pools. If the allocation percentage is 100% for the same pools, then the virtual capacity that is committed to the pools is 15 GiB. This configuration means that all the physical capacity of the pools is already allocated to volumes.
An allocation percentage that is higher than 100% is considered aggressive. The pools have insufficient physical capacity to satisfy the maximum allocation for all the thin-provisioned volumes in the pools. In such cases, use the Storage System Shortfall Percentage property to estimate how critical the shortage of space is for storage system pools.
Storage System Shortfall Percentage
The percentage of the remaining unallocated volume space in storage system pools that is not available to be allocated. The higher the percentage, the more critical the shortfall of pool space.
IBM Spectrum Control uses the following formula to determine this percentage: 
(unallocatable space ÷ (volume space - used volume space)) × 100
You can use this percentage to determine when the amount of overcommitted space in pools reaches a critically high level. For example, the physical space in pools might be less than the committed virtual space. In this case, the pools do not have enough space to fulfill the commitment to virtual space for a volume.
This value represents the percentage of the committed virtual space that is not available in pools. As more space is used over time by volumes while the pool capacity remains the same, this percentage increases.
For example, the physical capacity of pools is 70 GiB, but 150 GiB of virtual space is committed to thin-provisioned volumes. If the volumes are using 50 GiB, then there is still 100 GiB committed to those volumes (150 GiB - 50 GiB). There is only 20 GiB of available pool space (70 GiB - 50 GiB). Because only 20 GiB of pool space is available, 80 GiB of the committed space cannot be allocated (100 GiB - 20 GiB). In this case, the percentage of committed space that is unavailable is 80% (80 GiB ÷ 100 GiB × 100).
This value is only available for pools with thin-provisioned volumes.
Storage System Volume Capacity (GiB)
The amount of space on all volumes on the storage system.
Storage System Number of Volumes
The number of volumes on a resource.
Storage System Number of Disks
The number of physical disks on the storage system. For a resource that is running IBM Storage Virtualize and is configured as a back-end device, the value is the number of managed disks on the resource.
Storage System Overhead (GiB)
The amount of space that is used for system management. The amount of space also includes space that is reserved for redundancy.
Storage System Unallocated Disk Space (GiB)
The amount of disk space that can be added to a pool.
Storage System Volume Capacity Assigned to MDisks (GiB)
The amount of space that is on volumes that are assigned to a storage virtualizer to use as managed disks.
Storage System Disk Capacity (GiB)
The total amount of space that is on a physical disk on the storage system.
Storage System Total Disk Capacity (GiB)
The amount of space on physical disks on a storage system, including spare disks.
Storage System Cache (GiB)
The size of the cache on the storage system. This value is not shown for resources that are running IBM Storage Virtualize and are configured as back-end storage.
Storage System Assigned Volume Space (GiB)
The amount of space in the pool that is on volumes that are assigned to a server or storage virtualizer.
Storage System Volume Capacity for z/OS
The amount of space on all volumes on the storage system that the z/OS operating system can use.
Storage System Real Available Pool Space (GiB)
The amount of unused space in pools that have an associated soft size on an XIV or IBM Storage Accelerate. The soft size of a pool is the virtual size of a thin-provisioned pool.
Storage System Real Configured Pool Space (GiB)
The amount of storage space that is in pools that have an associated soft size on an XIV or IBM Storage Accelerate. The soft size of a pool is the virtual size of a thin-provisioned pool.
Storage System MDisk Available Space (GiB)
The amount of storage space that is available on a managed disk. This value is only available for resources that are running IBM Storage Virtualize and are configured as back-end storage.

Related reports

To open related reports, click the name of the storage system and then click the name of the report. You can open the following related reports:

  • Storage Systems Historical Capacity
  • Disks Capacity
  • Volumes Capacity
  • Pools Capacity