Apply and manage Headroom reduction

This topic describes how to apply and manage Headroom reduction to a workload. using the UI.

To use YAML, see Apply and manage Headroom reduction and Spot management with CRD.

Apply Headroom reduction using the UI

You apply the Headroom reduction solution to a workload using the Headroom reduction tab (“tab”) of the workload recommendation drawer (“drawer”).

You access the drawer from a recommendation in the Workloads tab.

Note: If the Insights agent is not installed in the cluster, recommendations are not displayed, so you cannot access the drawer. To install the Insights agent, see Install the Kompass Insights agent.

Configure draining mechanism

After you’ve applied Headroom reduction to a workload, you can change the draining mechanism from accelerated (default) to regular using YAML. For more information about the draining mechanisms, see How Headroom reduction works.

To enable and configure regular draining using YAML, see Apply and manage Headroom reduction and Spot management with CRD.

Headroom reduction tab

The following figure illustrates the Headroom reduction tab of the drawer:

The tab has these sections:

• General: See basic workload data, such as workload and cluster name, namespace, and cost. The tab name shows whether the solution is currently active or inactive.

• Overview: See why Kompass determined that Headroom reduction could optimize this workload, in terms of:

  • Utilization: how much vCPU was idle 90% of the time in the last 30 days

  • Application boot time: To see the expected reduction, hover the time link.

  • Potential savings from the default strategy

• Optimization strategy comparison: See the workload’s current metrics and compare those to the expected state after optimizing, per optimization strategy. You can see how Headroom reduction will change the minimum replica to lead to expected optimized utilization and cost metrics.

  • Default: Reduce minimum replicas to the lowest safe level, for the highest savings. Appropriate for most workloads.

  • Conservative: Reduce minimum replicas moderately, for moderate savings. Appropriate for sensitive or stateful workloads.

    Note: If there are very few Pods in a workload, the strategies may show an identical reduction of minimum replicas. That is a temporary situation that will likely change when more Pods are added.

    For more information about the optimization strategies, see Headroom reduction workload optimization.

• You can also see the expected change comparisons in graph form. On the graph, select which optimization strategy to see.

Prerequisites:

• The Compute agent is installed in the cluster.
  For more information, see Install the Kompass Compute agent.
  
  If you attempt to apply Headroom reduction before the Compute agent is installed, you can install it directly from the drawer.

To apply Headroom reduction to a workload from the UI:

1. From the Kompass > Workloads tab, identify a workload with a Headroom reduction recommendation in the Recommendations column.
   To show only workloads with specific recommendations, click .
   

2. Click the icon of the recommendation to apply.
   The workload recommendation drawer is displayed, showing the Headroom reduction tab. For more information about the data shown in the tab, see Headroom reduction tab.

3. Select an optimization strategy.

4. Click Apply Headroom reduction, then confirm.

The drawer closes and the Kompass > Workloads tab opens showing a message that the solution is being applied.

While the solution application is in progress, the icon of the applied solution is displayed in the workload’s Product status column in blue. For more information about what’s taking place during this time, see HiberScale technology.

After the solution is active (about an hour), the icon changes to green.

See changes in workload metrics

After Headroom reduction is active on a workload, you can see the impact that optimizing has made since the solution was first applied in the user interface Impact report section of the drawer.

These metrics are shown: changes in replicas, CPU utilization, and all-time savings.

To see changes in workload metrics:

• From the Kompass > Workloads tab, click the icon of a recommendation.

The workload tab is displayed in the drawer.

The tab also shows graphs for CPU used vs. requests and RAM used vs. requests.

Change the current Headroom reduction optimization strategy

After Headroom reduction is active on a workload, you can change the current optimization strategy. Changes take effect within an hour.

To change an optimization strategy:

1. From the Kompass > Workloads tab, click the icon of the recommendation to change.

   The workload drawer is displayed.

2. From the General section, click Change strategy.

3. Choose an alternate strategy.

4. Click Change strategy, then confirm.

A confirmation message is displayed.

Remove Headroom reduction from a workload

After Headroom reduction is active on a workload, you can remove the optimization. Removal takes effect within an hour.

To remove Headroom reduction from a workload:

1. From the Kompass > Workloads tab, click the icon of the recommendation to remove.
   The workload tab is displayed in the drawer.

2. From the General section, click Remove, then confirm.

A confirmation message is displayed.