Registry Entries for StorPort Miniport Drivers

StorPort defines a set of registry entries to configure the behavior of StorPort and miniport operations. Values are set in the scope of the miniport driver or per instance.

Service Entries

Registry entries for the miniport are keyed by the \Parameters subkey and the \Parameters\Device subkey of the miniport's services key. For individual adapter entries, the subkey is extended to include the adapter index, such as \Parameters\Device1.

Name: DriverParameter

  • Type: Any
  • Path:
    • Miniport scope: HKLM\System\CurrentControlSet\Services<miniport name>\Parameters\Device
    • Adapter scope: HKLM\System\CurrentControlSet\Services<miniport name>\Parameters\Device<adapter#>
  • Value : Any miniport specific data.
  • Description: Storport retrieves this registry data, and passes the buffer to the miniport as Parameter when it calls the miniport’s HwStorFindAdapter
  • Applies: Starting with Windows Server 2003.

Name: LinkDownTimeoutValue

  • Type: REG_DWORD
  • Path:
    • Miniport scope: HKLM\System\CurrentControlSet\Services<miniport name>\Parameters\Device<
    • Adapter scope: HKLM\System\CurrentControlSet\Services<miniport name>\Parameters\Device<adapter#>
  • Value:
    • Default: 30
    • Maximum: 600
    • Units: seconds
  • Description: This value is used by miniport driver to inform Storport, after the link goes down, how long StorPort should wait before restarting I/O to the miniport driver.
  • Applies: Starting with Windows Server 2003.

Name: MaximumLogicalUnit

  • Type: REG_DWORD
  • Path:
    • Miniport scope: HKLM\System\CurrentControlSet\Services<miniport name>\Parameters\Device
    • Adapter scope: HKLM\System\CurrentControlSet\Services<miniport name>\Parameters\Device<adapter#>
  • Value:
    • Default: 255
    • Maximum: 8 when set in the registry
  • Description: This value sets the maximum number of logical units (LUN) for a target device.
  • Applies: Starting with Windows Server 2003.

Name: MaximumUCXAddress

  • Type: REG_BINARY
  • Path:
    • Miniport scope: HKLM\System\CurrentControlSet\Services<miniport name>\Parameters\Device
    • Adapter scope: HKLM\System\CurrentControlSet\Services<miniport name>\Parameters\Device<adapter#>
  • Value:
    • Default: 0xffffffff
    • When 0, StorPort uses the default value.
  • Description: This value sets the maximum address value of an uncached extension.
  • Applies: Starting with Windows Server 2003.

Name: MinimumUCXAddress

  • Type: REG_BINARY
  • Path:
    • Miniport scope: HKLM\System\CurrentControlSet\Services<miniport name>\Parameters\Device
    • Adapter scope: HKLM\System\CurrentControlSet\Services<miniport name>\Parameters\Device<adapter#>
  • Value:
    • Default: 0x00000000
    • When MinimumUCXAddress >= MaximumUCXAddress - PAGE_SIZE, StorPort uses the default value.
  • Description: This value sets the minimum address value of an uncached extension.
  • Applies: Starting with Windows Server 2003.

Name: UncachedExtAlignment

  • Type: REG_DWORD
  • Path:
    • Miniport scope: HKLM\System\CurrentControlSet\Services<miniport name>\Parameters\Device
    • Adapter scope: HKLM\System\CurrentControlSet\Services<miniport name>\Parameters\Device<adapter#>
  • Value:
    • Default: 0
    • Minimum: 3
    • Maximum: 16
  • Description: StorPort uses this value to calculate a base 2 exponent (e.g. 1 << value) to use as an alignment value for the uncached extension buffer allocation.
  • Applies: Starting with Windows Server 2003.

Name: NumberOfRequests

  • Type: REG_DWORD
  • Path:
    • Miniport scope: HKLM\System\CurrentControlSet\Services<miniport name>\Parameters\Device
    • Adapter scope: HKLM\System\CurrentControlSet\Services<miniport name>\Parameters\Device<adapter#>
  • Value:
    • Default: 1000
    • Minimum: 16
    • Maximum: 255
  • Description: The number or requests that an adapter can process. When set, the range is smaller than the default.

Name: BusType

  • Type: REG_DWORD
  • Path:
    • Miniport scope: HKLM\System\CurrentControlSet\Services<miniport name>\Parameters
  • Value:
    • Default: 6, BusTypeFiber
    • Maximum: 0x7f, any value greater is treated as the default
  • Description: This value is used to indicate the bus type for the adapters that the miniport driver manages. The value corresponds to the STORAGE_BUS_TYPE bus enumeration type.
  • Applies: Starting with Windows Server 2003.

Name: IoTimeoutValue

  • Type: REG_DWORD
  • Path:
    • Miniport scope: HKLM\System\CurrentControlSet\Services<miniport name>\Parameters
  • Value:
    • Minimum: 0
    • Maximum: 65535
    • Units: seconds
  • Description: Indicates the I/O timeout value for devices managed by the miniport driver. If this registry value doesn’t exist, the system will use the global disk I/O timeout value.
  • Applies: Starting with Windows 8.

Name: IoLatencyCap

  • Type: REG_DWORD
  • Path:
    • Miniport scope: HKLM\System\CurrentControlSet\Services<miniport name>\Parameters
  • Value:
    • Default: 0
    • Units: milliseconds
  • Description: If this registry value is > 0, StorPort will hold incoming I/O requests in the queue when any I/O request sent to miniport driver has not been completed in the period of time specified.
  • Applies: Starting with Windows 8.

Device Enumeration Entries

Name: TotalSenseDataBytes

  • Type: REG_DWORD
  • Path:
    • Adapter scope: HKLM\System\CurrentControlSet\Enum<instance path>\Device Parameters\StorPort
  • Value:
    • Default: 255
    • Minimum: 18
    • Maximum: 255
    • Units: bytes
  • Description: Indicates the Sense Data size that the miniport driver returns to StorPort.
  • Applies: Starting with Windows Server 2003.

Name: QueueFullWaitIoPercentage

  • Type: REG_DWORD
  • Path:
    • Logical unit scope: HKLM\CurrentControlSet\Enum\SCSI<HardwareId><InstanceId>\Device Parameters\StorPort
  • Value:
    • Default: 25
    • Maximum: 100
    • Units: Percentage of queue depth
  • Description: When the miniport reports device-busy by setting SCSISTAT_QUEUE_FULL in ScsiStatus of a SRB, StorPort pauses the logical unit queue and waits until a certain amount I/O requests are completed by the miniport before sending any further requests. The amount of I/O requests StorPort waits on is calculated using this registry value relative to the count of I/O requests currently sent to the miniport.
  • Applies: Starting with Windows Server 2003.

Name: BusyPauseTime

  • Type: REG_DWORD
  • Path:
    • Logical unit scope: HKLM\CurrentControlSet\Enum\SCSI<HardwareId><InstanceId>\Device Parameters\StorPort
  • Value:
    • Default: 250
    • Units: milliseconds
  • Description: When the miniport reports device-busy by setting SRB_STATUS_BUSY in the SrbStatus of a SRB, StorPort pauses the unit queue and waits for the specified amount time before starting sending I/O requests again.
  • Applies: Starting with Windows Server 2003.

Name: BusyRetryCount

  • Type: REG_DWORD
  • Path:
    • Logical unit scope: HKLM\CurrentControlSet\Enum\SCSI<HardwareId><InstanceId>\Device Parameters\StorPort
  • Value:
    • Default: 20
  • Description: The retry for StorPort to reissue an Srb when the miniport reports device busy or link down.
  • Applies: Starting with Windows Server 2003.

Name: EnableIdlePowerManagement

  • Type: REG_DWORD
  • Path:
    • Adapter scope: HKLM\System\CurrentControlSet\Enum<instance path>\Device Parameters\StorPort
  • Value:
    • Default: 0, disabled
  • Description: If this registry value is > 0, then idle power management is enabled. The idle power management is for logical units connected to the adapter.
  • Applies: Starting with Windows 7.

Name: DisableIdlePowerManagement

  • Type: REG_DWORD
  • Path:
    • Logical unit scope: HKLM\CurrentControlSet\Enum\SCSI<HardwareId><InstanceId>\Device Parameters\StorPort
  • Value:
    • Default: 0, enabled
  • Description: If this registry value is > 0, then idle power management is disabled for this logical unit.
  • Applies: Starting with Windows 8.

Name: MinimumIdleTimeoutInMS

  • Type: REG_DWORD
  • Path:
    • Logical unit scope: HKLM\CurrentControlSet\Enum\SCSI<HardwareId><InstanceId>\Device Parameters\StorPort
  • Value:
    • Default: MAXULONG, indicating unset. If the miniport provides no timeout value, the actual default value is 5 * 60 * 1000, which is 5 minutes.
    • Units: milliseconds
  • Description: This value specifies the minimum amount of time the power framework must wait to power down a logical unit once it is at idle.
  • Applies: Starting with Windows 8.

Name: DisableRuntimePowerManagement

  • Type: REG_DWORD
  • Path
    • Adapter scope: HKLM\System\CurrentControlSet\Enum<instance path>\Device Parameters\StorPort
  • Value:
    • Default: 0, enabled
  • Description: If the value > 0, then runtime power management for adapter is disabled. This disables runtime power management for specific adapter. NOTE: Runtime power management for devices attached to this adapter is not affected.
  • Applies: Starting with Windows 8.

Name: IdleTimeoutInMS

  • Type: REG_DWORD
  • Path
    • Adapter scope: HKLM\System\CurrentControlSet\Enum<instance path>\Device Parameters\StorPort
  • Value:
    • Default: 60
    • Units: seconds
  • Description: Specifies the time that runtime power framework needs to wait before powering down an idle adapter.
  • Applies: Starting with Windows 8.

Name: DisableD3Cold

  • Type: REG_DWORD
  • Path
    • Adapter scope: HKLM\System\CurrentControlSet\Enum<instance path>\Device Parameters\StorPort
  • Value:
    • Default: enabled (when D3Cold is supported)
  • Description: If the value > 0, then D3Cold support for the adapter is disabled.
  • Applies: Starting with Windows 8.