smis-block-performance.rst

SMI-S Block Server Performance Subprofile

This profile provides I/O statistics for various :ref:`CIM_StorageExtent<CIM-StorageExtent>` subclasses.

OpenLMI-Storage implements the Block Server Performance Subprofile with these adjustments:

• Applications cannot create custom manifests, i.e. :ref:`LMI_BlockStatisticsService.AddOrModifyManifest<CIM-BlockStatisticsService-AddOrModifyManifest>` is not implemented.
• We provide :ref:`LMI_BlockStorageStatisticalData<LMI-BlockStorageStatisticalData>` for every :ref:`CIM_StorageExtent<CIM-StorageExtent>` subclass and not only for disk drives. :ref:`LMI_BlockStorageStatisticalData.ElementType<LMI-BlockStorageStatisticalData-ElementType>` property is always set to 9, i.e. Extent.
• There is no sampling interval. OpenLMI always reports current values when returning :ref:`LMI_BlockStorageStatisticalData<LMI-BlockStorageStatisticalData>` instance.

Note

Even though properties in :ref:`LMI_BlockStorageStatisticalData<LMI-BlockStorageStatisticalData>` are 64-bit, they are tracked as 32-bit on systems with 32-bit kernel. They can wrap pretty quickly on modern hardware.

For example, on i686 with iSCSI drive on 10Gb/s link, the KBytesRead counter can wrap in approximately 27 minutes.

With 64-bit kernels, these counters are tracked in 64-bits and they wrap once in a few years.

Implementation

All mandatory classes and methods are implemented.

Classes

Implemented SMI-S classes:

• :ref:`LMI_BlockStorageStatisticalData<LMI-BlockStorageStatisticalData>`
• :ref:`LMI_StorageElementStatisticalData<LMI-StorageElementStatisticalData>`
• :ref:`LMI_StorageStatisticsCollection<LMI-StorageStatisticsCollection>`
• :ref:`LMI_MemberOfStorageStatisticsCollection<LMI-MemberOfStorageStatisticsCollection>`
• :ref:`LMI_HostedStorageStatisticsCollection<LMI-HostedStorageStatisticsCollection>`
• :ref:`LMI_BlockStatisticsService<LMI-BlockStatisticsService>`
• :ref:`LMI_BlockStatisticsCapabilities<LMI-BlockStatisticsCapabilities>`
• :ref:`LMI_BlockStatisticsManifest<LMI-BlockStatisticsManifest>`
• :ref:`LMI_BlockStatisticsManifestCollection<LMI-BlockStatisticsManifestCollection>`
• :ref:`LMI_MemberOfBlockStatisticsManifestCollection<LMI-MemberOfBlockStatisticsManifestCollection>`
• :ref:`LMI_AssociatedBlockStatisticsManifestCollection<LMI-AssociatedBlockStatisticsManifestCollection>`

Methods

Implemented methods:

• :ref:`LMI_BlockStatisticsService.GetStatisticsCollection<LMI-BlockStatisticsService-GetStatisticsCollection>`