Manage System Data Exclusion Windows

Data Exclusion Windows are used for calculating headroom and suitability.

About this task

Peaks in storage system statistics can occur due to:
  • Anomalies or unusual events
  • Recurring maintenance during off-hours that fully loads the storage system

Due to the way this data is condensed and used, unexpected headroom and suitability results can occur.

There are two ways to improve the handling of these cases:
  • One-time exclusion period—when the one-time exclusion period value is set, all statistics before this time are ignored. This helps resolve the first case above, where a significant one time peak distorts the results due to reliance on two weeks of data points. This is set system-wide for all components.
  • Recurring exclusion period—You can select one or more 4 hour windows to use in admissibility checks. This is set system-wide for all components. Recurring exclusion periods are repeating periods of selected weekday or time slot combinations where collected data is ignored for the purposes of compliance and admissibility considerations. The data is still collected and reported, but it is not used in those calculations.
Before you begin:
  • The user must have at least StorageAdmin permissions.

To manage system data exclusion windows:

Steps

  1. Do one of the following:
    • Select the storage system from the all systems dashboard. Click the SG Compliance panel and In the Actions panel, select EXCLUDE DATA.
    • Select the storage system and click STORAGE > Storage Groups, select a storage group with compliance, navigate to its Compliance tab and select Exclude Data > System.
  2. Select All components, for suitability or Back-end components only, for headroom.

Results

The dialog that is displayed allows you to view and set the one-time exclusion period and recurring exclusion periods for a selected storage system. It consists of two panels. The One-time Exclusion Period panel displays 84 component utilizations (two weeks worth of data) in a single chart that allows you to set the one-time exclusion period value from a given time slot, resulting in all time slots before the selected time slot being ignored for the purposes of calculating compliance and admissibility values. The Recurring Exclusion Periods panel displays the same data, but in a one-week format that allows you to select repeating recurring exclusion periods during which any collected data is ignored.

Each bar in the chart represents a utilization score that is calculated for that time slot. The score itself is the highest value of four component types, that is, the “worst performing” of the four components is the one that determines the overall value returned. The exact type and identifier of the selected component can be seen in the tooltip for a specific bar. The four component types that are represented in the bars are:
  • Front End Port
  • BackEnd Port
  • RDF Port
  • Thin Pool

The bars in both panels represent the same data using the same color coding scheme. The colors of the bars signify the following states:

Green represents a utilization value that meets the best practice limit.

Red represents a utilization value that exceeds the best practice limit.

Gray represents a weighted response time that is being ignored before the one-time exclusion period.

Light Gray represents a weighted response time that is being ignored before the recurring exclusion period.

No Bar – If no data was collected or calculated during a time slot, there is no bar present.

The One-time Exclusion Period panel consists of a chart that is labeled with the component utilization value as the y-axis and the time slot as the x-axis. Each time slot is a four-hour window during which data was collected and a utilization score was calculated. There is also a horizontal line representing the best practice utilization of 100%. The x -axis is labeled with the dates of the time slots, that is, the dates of the midnight time slots are labeled with that date and other time slots are blank.

The top-right of this panel has a filter which allows you to include all components thta are used in utilizations calculations or filter for only those used in headroom calculations. This can be helpful when headroom values are causing suitability problems in other areas, but those issues are masked by other component utilizations on this chart. The filters are: All components, for suitability (the default selection) and Back-end components only, for headroom. When you select a value, the page is reloaded with data from the server that is filtered according to the selection made. Both charts are updated to reflect this data.

When the user selects a value, the page IS reloaded with data from the server, and filtered according to the selection made. Both charts are updated to reflect this data.

You can select and set a time slot before which all collected data is ignored. You select the time slot by clicking on the desired bar. The selected bar and all previous bars are changed to the one-time exclusion period coloring reflecting this selection. In addition, one-time exclusion period selection is also dynamically displayed in the Recurring Exclusion Periods chart as selections are made. If you try to set the selection to the last bar on the right, an error is displayed and the action is not allowed. In addition, selection is also dynamically displayed in the Windows chart as selections are made. You can deselect a selected bar by clicking it again. The chart then reverts to the value set when the page was loaded.

One-time exclusion period bars are only displayed in the Recurring Exclusion Periods chart under these conditions:
  • Both buckets corresponding to the Recurring Exclusion Periods chart slot are before the one-time exclusion period.
  • One of the buckets is before the one-time exclusion period and the other bucket has no data collected.
The panel has two buttons to set and clear any changes that are made:
  • Set One-time Exclusion—writes the selected one-time exclusion period value to the database. This value will then be in effect and will be shown in all future views of this page. This button is enabled when a one-time exclusion period is selected. Clicking OK confirms the operation.
  • Clear One-time Exclusion—clears any previously set one-time exclusion value. This button is only enabled if a one-time exclusion value is set when the page is first loaded. Clicking OK confirms the operation.

The Recurring Exclusion Periods panel consists of seven charts, one for each day of the week. Each chart has a bar for each four-hour time slot during which data is collected and a utilization score is calculated. Each bar represents two bars tha are shown in the One-time Exclusion Period Panel chart. The bar shown in this chart is the highest value (“worst performing”) bar of the two One-time Exclusion Period Panel bars.

One-time exclusion period bars are only displayed in the Recurring Exclusion Periods chart under the following conditions:
  • Both buckets corresponding to the Recurring Exclusion Periods chart slot are in the one-time exclusion period.
  • One of the buckets is in the one-time exclusion period and the other bucket has no data collected.

In this panel, you click a time slot to select or deselect it. Clicking on a selected time slot deselects it. As selections are made, both charts are dynamically updated with the appropriate color coding.

The panel has two buttons to set and clear any changes that are made:
  • Set Recurring Exclusions—writes the selected recurring exclusions period value or values to the database. These values will then be in effect and will be shown in all future views of this page. This button is enabled when a recurring exclusion period is selected. Clicking OK confirms the operation.
  • Clear Recurring Exclusions—clears any previously set recurring exclusion period values. This button is only enabled if a recurring exclusion period value is set when the page is first loaded. Clicking OK confirms the operation.

There is a panel at the bottom of the page that contains the legend indicating the meanings that are associated with the different bar colors. On the right-hand side in this panel, there is text detailing the last time a one-time exclusion period or Window was changed. If you hover over this text, the name of the user (fully qualified user name) that performed the last update operation is displayed. If the database has never had a one-time exclusion period or Window set, the field and tooltip text displays Not yet modified.

You can drag the mouse to zoom in on the graphs. This results in the display of a Reset zoom button that you can click to zoom out to the original zoom setting.

Alerts

There is a system alert generated each time that a user changes a one-time exclusion period value or a recurring exclusion period value.