View Storage Group Compliance view

Storage groups are a collection of devices that are stored on the storage system. An application, a server, or a collection of servers use them.

Prerequisites

The storage system must be running HYPERMAX OS 5977 or PowerMaxOS 5978.

About this task

Definitions:

  • Workload Skew—Capacity and load pairs represent skew. There are two sources of skew for a storage group. The first is using device stats. The other is using SG_PER_POOL chunks. There is an algorithm in WLP to merge these two lists to provide a usable skew profile. A skew profile is only useful if you have multiple chunks. If an SG has a single device, there is not enough data to calculate skew, the corresponding storage group per pool metrics can be used. Similarly, if a storage system has only one pool, the device stats are more meaningful for skew.
  • Workload Mixture—The mixture is the distribution of various I/O types as percentages of the total IOPS. Workload mixture is useful for determining, for example, whether a workload is heavy read or heavy write, whether I/O operations are mostly random or mostly sequential.

To view the Storage Group (SG) Compliance view:

Steps

  1. Select the storage system.
  2. Select Storage > Storage Groups to open the Storage Groups View.
  3. Select a storage group with compliance that is indicated (by a green icon) and click An icon showing the letter i to view its details.
  4. Select View All Details.
  5. Click the compliance icon to view the Compliance tab.

    Charts are displayed for the following:

    • Response Time chart—This chart displays wait time weighted response time and (if applicable) the target service level response time band. The following section explains the data in the chart:
      • Actual: Running I/O to Storage Group - Wait time weighted response time is calculated in buckets and displayed. If a bucket has no data, 0 is displayed.
      • Actual: No I/O to Storage Group - 0s are displayed.
      • Planned: SL Response Time Max and SL Response Time Min are displayed as a data band across the timeline, and is labeled "Planned". If the service level is Optimized, no plan is displayed, because there is no Response Time band for Optimized.
      • Gold Range - range for the Gold service level
      • Without SG Exclusion - click to view the response time without SG exclusion applied.
      • System Excluded Data: If a recurring exclusion has been set in the System Exclusion Windows dialog, the windows are represented by vertical gray plot bands.
      • Last Processed: A 2 px dotted plot line marks the most recent SPA HOURLY timestamp that was processed by SPA for a given metric. It is not represented in the legend, but if you hover, you can see the associated timestamp. In normal successful processing, the timestamp acts as a "Where am I" indicator. If WLP stops processing for some reason, it is a subtle debugging helper.
      Click View Details to view the Compliance State, Platinum Threshold, the weighted response time for 4 hours, and the weighted response time for 2 weeks.
    • IOPS chart—This chart switches between IO/sec and MB/sec, displaying I/O rate weighted metric values, "planned" values, and (if set) Host I/O Limits. The following section explains the data in the chart:
      • Actual: Running I/O to Storage Group— I/O Rate weighted total IOPS (or total MBPS) are calculated in buckets and displayed. If a bucket has no data, 0 is displayed.
      • Actual: No I/O to Storage Group—0s are displayed.
      • Planned: Host I/O Limits for Standalone SG—Host I/O Limit is displayed as a static value across the timeline. Host I/O Limit is shown on the chart only if it impacts. For example, if the MBPS host I/O limit is set, and you have not selected IOPS , you do not see anything unless you switch to MBPS.
      • Planned: Host I/O Limits for Child SG, no limit for the parent SG—Host I/O Limit is displayed as a static value across the timeline. Host I/O Limit is shown on the chart only if it impacts. For example, if the MBPS host I/O limit is set, and you have IOPS selected, you do not see anything unless you switch to MBPS.
      • Planned: No Host I/O Limits for Child SG and parent SG—If a cascaded SG has a host I/O limit set at the parent, but no direct limit of its own, the host I/O limit of any given child would be the parent limit minus whatever the siblings are using.
      • Planned: Host I/O Limits for Child SG and parent SG—If a cascaded SG has a host I/O limit set at the parent, and a direct limit of its own, the host I/O limit of any given child would be the more limiting of the parent limit minus whatever the siblings are using, or the child SGs own limit.
      • Excluded Data: If a recurring exclusion has been set by the Exclusion Windows dialog, the windows are represented by vertical gray plot bands.
      • Last Processed: A 2 px dotted plot line marks the most recent SPA HOURLY timestamp that SPA has processed for a given metric. It is not represented in the legend, but if you hover, you can see the timestamp that is associated. In normal successful/processing, the timestamp acts as a "Where am I" indicator. If WLP stops processing for some reason, it is a subtle debugging helper.
    • Workload Skew chart—This chart compares actual workload skew - represented by cumulative capacity and load percentages (ordered by access density) - to planned skew. If there is no I/O data, Actual is displayed as 50% skew - a straight line from (0,0) to (100,100). If there is one device in SG and only one thin pool, then the merged device and SG per pool skew profile does not provide enough data points and is displayed as 50% skew - a straight line from (0,0) to (100,100). If I/O is running to the SG, the skew is a logarithmic curve (or stepped line graph in some cases).
    • I/O Mixture chart—This chart compares actual workload mixture to planned workload mixture. The inner pie represents the actual I/O distribution. The outer donut represents the planned mixture. If there is no I/O to the storage group, the mixture distribution is equal percentages for each I/O type (20% read hit, 20% sequential write, and so on) and the tooltip displays the corresponding I/O sizes as 0 KB.

    Select the Show Plan slider to turn on or turn off the display of the plan. The plan is a reference point that is used for comparison, and is a two week expiring performance reservation for subsequent provisioning suitability calculations.

    The following controls are available: