About HPE Nimble storage systems

Additional parameters for HPE Nimble storage systems

You can view the following parameters in the "Advanced" section of a volume screen. A volume screen is accessible from the associated storage system or from the Volumes selection in the main menu:
  • Cache pinning: This is applicable for hybrid (a mix of flash and mechanical storage) arrays, and provides a 100 percent cache hit rate for specific volumes (for example, volumes dedicated to critical applications), and delivers the response times of an all-flash storage system. A volume is pinned when the entire active volume is placed in cache; associated snapshot (inactive) blocks are not pinned. All incoming data after that point is pinned. The number of volumes that can be pinned is limited by the size of the volumes and amount of available cache.

  • Performance policy: Defined on the array, a performance policy helps optimize the performance of the volume based on the characteristics of the application using the volume. The policy defines the block size, whether deduplication, compression, and caching options are enabled, and defines behaviors when certain limits are exceeded. Based on the selected performance policy, the application category and block size are displayed. Once a volume has been created with a given block size, only performance policies with the same block size can be used.

  • Volume set

  • Folders: Folders are containers for holding volumes. They are used most often for organization, management, and further delegation. Folders provide simple volume grouping for ease of management.

  • IOPS limit and Data transfer limit: IOPS (input/output requests per second) and data transfer MiB/s (mebibytes per second) limits are used in conjunction with the volume block size to govern Quality of Service (QoS) for volumes. The input and output requests are throttled when either the IOPS limit or the data transfer MiB/s limit is met. On the array, the IOPS and data transfer limits may also be applied to a folder to throttle requests to all volumes in the folder when the cumulative IOPS of all the volumes under that folder exceeds the folder IOPS limit or when the cumulative throughput of all the volumes under that folder exceeds the folder MiB/s limit. When this happens, all the volumes are throttled equally.