Workload Balancing Report Glossary
Note:
XenCenter YYYY.x.x is not yet supported for use with Citrix Hypervisor 8.2 CU1 in production environments. To manage your Citrix Hypervisor 8.2 CU1 production environment, use XenCenter 8.2.7. For more information, see the XenCenter 8.2.7 documentation.
You can install XenCenter 8.2.7 and XenCenter YYYY.x.x on the same system. Installing XenCenter YYYY.x.x does not overwrite your XenCenter 8.2.7 installation.
Workload Balancing provides the following reports.
Chargeback utilization analysis
You can use the Chargeback Utilization Analysis report (“chargeback report”) to determine how much of a resource (such as a physical server) a department within your organization used. Specifically, the report shows information about all the virtual machines in your pool, including their availability and resource utilization. Since this report shows virtual machine availability (“up time”), it can help you demonstrate Service Level Agreements compliance and availability.
The chargeback report can help you implement a simple chargeback solution and facilitate billing. To bill customers for usage of a specific resource, generate the report, save it as Excel. You can then customize the spreadsheet data to include your price per unit or import the Excel data into your billing system.
If you know that you want to bill internal or external customers for virtual machine usage, consider incorporating department or customer names in your VM naming conventions. This convention makes reading chargeback reports easier.
The resource reporting in the chargeback report is, sometimes, based on the allocation of physical resources to individual VMs.
Likewise, because XenServer lets you allocate fixed or automatic allocations of memory, the average memory data in this report is based on the amount of memory currently allocated to the VM, whether it is through a fixed memory allocation or an automatically adjusting memory allocation (Dynamic Memory Control).
The chargeback report contains the following columns of data:
- VM Name. The name of the virtual machine to which the data in the columns in that row applies.
- VM Uptime. The number of minutes the virtual machine was powered on (or, more specifically, appears with a green icon beside it in XenCenter).
- vCPU Allocation. The number of virtual CPUs configured on the virtual machine. Each virtual CPU receives an equal share of the physical CPUs on the host. For example, if you configured eight virtual CPUs on a host that contains two physical CPUs and this column had “1” in it, then this value is equal to 2/16 of the total processing power on the host.
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Minimum CPU Usage (%). The lowest recorded value for the virtual CPU utilization in the reporting period. This value is expressed as a percentage of the VM’s virtual CPU capacity. The capacity is based on the number of virtual CPUs allocated to the VM. For example, if you allocated one virtual CPU to the VM, Minimum CPU Usage represents the lowest percentage of virtual CPU usage XenServer recorded. If you allocated two virtual CPUs to the VM, the value in this column represents the lowest usage of the combined capacity of both virtual CPUs. The value is expressed as a percentage.
Ultimately, the percentage of CPU usage represents the lowest recorded workload that the virtual CPU handled. For example, if you allocate one virtual CPU to a VM and the physical CPU on the host is 2.4 GHz, you are allocating one-eighth of 2.4 GHz to the VM. This behavior means that if the VM’s allocated capacity is 0.3 GHz, or 300 MHz, and the Minimum CPU Usage for the virtual machine was 20%, the VM’s lowest usage of the physical host’s CPU during the reporting period was 60 MHz.
- Maximum CPU Usage (%). The highest percentage of the virtual machine’s virtual CPU capacity that the virtual machine consumed during the reporting period. The CPU capacity consumed is a percentage of the virtual CPU capacity you allocated to the virtual machine. For example, if you allocated one virtual CPU to the VM, the Maximum CPU Usage represents the highest recorded percentage of virtual CPU usage during the time reported. If you allocated two virtual CPUs to the virtual machine, the value in this column represents the highest utilization from the combined capacity of both virtual CPUs.
- Average CPU Usage (%). The average amount, expressed as a percentage, of the virtual machine’s virtual CPU capacity that was in use during the reporting period. The CPU capacity is the virtual CPU capacity you allocated to the virtual machine. If you allocated two virtual CPUs to the virtual machine, the value in this column represents the average utilization from the combined capacity of both virtual CPUs.
- Total Storage Allocation (GB). The amount of disk space that is currently allocated to the virtual machine at the time the report was run. Frequently, unless you modified it, this disk space is the amount of disk space you allocated to the virtual machine when you created it.
- Virtual NIC Allocation. The number of virtual interfaces (VIFs) allocated to the virtual machine.
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Current Minimum Dynamic Memory (MB).
- Fixed memory allocation. If you assigned a virtual machine a fixed amount of memory (for example, 1,024 MB), the same amount of memory appears in the following columns: Current Minimum Dynamic Memory (MB), Current Maximum Dynamic Memory (MB), Current Assigned Memory (MB), and Average Assigned Memory (MB).
- Dynamic memory allocation. If you configured XenServer to adjust a VM’s memory automatically based on a range, this column shows the minimum amount of memory specified in the range. For example, if in the Memory Settings dialog box in XenCenter, you selected the Automatically allocate memory within this range option for this virtual machine and then specified the range values as 1,024 MB as the minimum memory and 2,048 MB as the maximum memory, then 1,024 MB appears in the Current Minimum Dynamic Memory (MB) column.
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Current Maximum Dynamic Memory (MB).
- Dynamic memory allocation. If XenServer is set to adjust a VM’s memory automatically based on a range, this column shows the maximum amount of memory specified in the range. For example, if the memory range you provided was 1,024 MB minimum and 2,048 MB maximum, then 2,048 MB appears in the Current Maximum Dynamic Memory (MB) column.
- Fixed memory allocation. If you assign a VM a fixed amount of memory (for example, 1,024 MB), the same amount of memory appears in the following columns: Current Minimum Dynamic Memory (MB), Current Maximum Dynamic Memory (MB), Current Assigned Memory (MB), and Average Assigned Memory (MB).
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Current Assigned Memory (MB).
- Dynamic memory allocation. When Dynamic Memory Control is configured, this value indicates the amount of memory XenServer is allocating to the virtual machine when the report is run.
- Fixed memory allocation. If you assign a virtual machine a fixed amount of memory (for example, 1,024 MB), the same amount of memory appears in the following columns: Current Minimum Dynamic Memory (MB), Current Maximum Dynamic Memory (MB), Current Assigned Memory (MB), and Average Assigned Memory (MB).
Note:
If you change the virtual machine’s memory allocation immediately before running this report, the value reflected in this column reflects the new memory allocation you configured.
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Average Assigned Memory (MB).
- Dynamic memory allocation. When Dynamic Memory Control is configured, this value indicates the average amount of memory XenServer allocated to the virtual machine over the reporting period.
- Fixed memory allocation. If you assign a virtual machine a fixed amount of memory (for example, 1,024 MB), the same amount of memory appears in the following columns: Current Minimum Dynamic Memory (MB), Current Maximum Dynamic Memory (MB), Current Assigned Memory (MB), and Average Assigned Memory (MB).
Note:
If you change the virtual machine’s memory allocation immediately before running this report, the value displayed in this column might not change from what it would have previously displayed. The value in this column reflects the average over the time period.
- Average Network Reads (BPS). The average amount of data (in bits per second) the virtual machine received during the reporting period.
- Average Network Writes (BPS). The average amount of data (in bits per second) the virtual machine sent during the reporting period.
- Average Network Usage (BPS). The combined total (in bits per second) of the Average Network Reads and Average Network Writes. For example, if a virtual machine sent, on average, 1,027 bits per second and received, on average, 23,831 bits per second over the reporting period, then the Average Network Usage would be the combined total of these two values: 24,858 bits per second.
- Total Network Usage (BPS). The total of all network read and write transactions in bits per second over the reporting period.
Host health history
This report displays the performance of resources (CPU, memory, network reads, and network writes) on a specific host in relation to threshold values.
The colored lines (red, green, yellow) represent your threshold values. You can use this report with the Pool Health report for a host to determine how a particular host’s performance might be affecting overall pool health. When you are editing the performance thresholds, you can use this report for insight into the host performance.
You can display resource utilization as a daily or hourly average. The hourly average lets you see the busiest hours of the day, averaged, for the time period.
To view report data grouped by hour, expand + Click to view report data grouped by house for the time period under the Host Health History title bar.
Workload Balancing displays the average for each hour for the time period you set. The data point is based on a utilization average for that hour for all days in the time period. For example, in a report for May 1, 2009, to May 15, 2009, the Average CPU Usage data point represents the resource utilization of all 15 days at 12:00 hours combined as an average. That is, if CPU utilization was 82% at 12 PM on May 1, 88% at 12 PM on May 2, and 75% on all other days, the average displayed for 12 PM is 76.3%.
Pool optimization performance history
The optimization performance report displays optimization events (that is, when you optimized a resource pool) against that pool’s average resource usage. Specifically, it displays resource usage for CPU, memory, network reads, and network writes.
The dotted line represents the average usage across the pool over the period of days you select. A blue bar indicates the day on which you optimized the pool.
This report can help you determine if Workload Balancing is working successfully in your environment. You can use this report to see what led up to optimization events (that is, the resource usage before Workload Balancing recommended optimizing).
This report displays average resource usage for the day. It does not display the peak utilization, such as when the system is stressed. You can also use this report to see how a resource pool is performing if Workload Balancing is not making optimization recommendations.
In general, resource usage declines or remains steady after an optimization event. If you do not see improved resource usage after optimization, consider readjusting threshold values. Also, consider whether the resource pool has too many virtual machines and whether new virtual machines were added or removed during the time frame you specified.
Pool audit trail
This report displays the contents of Audit Log, a feature designed to log attempts to perform unauthorized actions and select authorized actions. These actions include import/export, host and pool backups, and guest and host console access. The report gives more meaningful information when XenServer administrators are given their own user accounts with distinct roles assigned to them using the Role-Based Access Control feature. For information about the Audit Log feature, see the audit log documentation in the Workload Balancing documentation.
Important:>
To run the audit log report, the Audit Logging feature must be enabled. By default, Audit Log is always enabled in the Workload Balancing virtual appliance.
The enhanced Pool Audit Trail feature allows you to specify the granularity of the audit log report. You can also search and filter the audit trail logs by specific users, objects, and by time. The Pool Audit Trail Granularity is set to Minimum by default. This option captures limited amount of data for specific users and object types. You can modify the setting at any time based on the level of detail you would require in your report. For example, set the granularity to Medium for a user-friendly report of the audit log. If you require a detailed report, set the option to Maximum.
To modify the Pool Audit Trail Granularity setting:
- Select the pool in the Infrastructure view, select the WLB tab, and then select Settings.
- In the left pane, select Advanced.
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On the Advanced page, select the Pool Audit Trail Report Granularity list and select an option from the list.
Important:
Select the granularity based on your audit log requirements. For example, if you set your audit log report granularity to Minimum, the audit report only captures limited amount of data for specific users and object types. If you set the granularity to Medium, the report provides a user-friendly report of the audit log. If you choose to set the granularity to Maximum, the report contains detailed information about the audit log report. Setting the audit log report to Maximum can cause the Workload Balancing server to use more disk space and memory.
- Click OK to confirm your changes.
This report displays the following:
- Time. The time XenServer recorded the user’s action.
- User Name. The name of the person who created the session in which the action was performed. Sometimes, this value might be the User ID.
- Event Object. The object that was the subject of the action (for example, a virtual machine).
- Event Action. The action that occurred. For definitions of these actions, see Audit Log Event Names.
- Access. Whether the user had permission to perform the action.
- Object Name. The name of the object (for example, the name of the virtual machine).
- Object UUID. The UUID of the object (for example, the UUID of the virtual machine).
- Succeeded. This value provides the status of the action (that is, whether it was successful).
Pool Health
The pool health report displays the percentage of time a resource pool and its hosts spent in four different threshold ranges: Critical, High, Medium, and Low. You can use the Pool Health report to evaluate the effectiveness of your performance thresholds.
A few points about interpreting this report:
- Resource utilization in the Average Medium Threshold (blue) is the optimum resource utilization regardless of the placement strategy you selected. Likewise, the blue section on the pie chart indicates the amount of time that the host used resources optimally.
- Resource utilization in the Average Low Threshold Percent (green) is not necessarily positive. Whether Low resource utilization is positive depends on your placement strategy. For example, if your placement strategy is Maximum Density and most of the time your resource usage was green, Workload Balancing might not be fitting the maximum number of virtual machines possible on that host or pool. If so, adjust your performance threshold values until most of your resource utilization falls into the Average Medium (blue) threshold range.
- Resource utilization in the Average Critical Threshold Percent (red) indicates the amount of time average resource utilization met or exceeded the Critical threshold value.
If you double-click on a pie chart for a host’s resource usage, XenCenter displays the Host Health History report for that resource on that host. Clicking the Back to Parent Report toolbar button returns you to the Pool Health history report. Note: This button is only available in drill-through reports, such as the Pool Health report.
If you find most of your report results are not in the Average Medium Threshold range, you probably need to adjust the Critical threshold for this pool. While Workload Balancing provides default threshold settings, these defaults are not effective in all environments. If you do not have the thresholds adjusted to the correct level for your environment, Workload Balancing’s optimization and placement recommendations might not be appropriate. For more information, see Changing the Critical Thresholds.
Note:
The High, Medium, and Low threshold ranges are based on the Critical threshold value.
Pool health history
This report provides a line graph of resource utilization on all physical hosts in a pool over time. It lets you see the trend of resource utilization - if it tends to be increasing in relation to your thresholds (Critical, High, Medium, and Low). You can evaluate the effectiveness of your performance thresholds by monitoring the trends of the data points in this report.
Workload Balancing extrapolates the threshold ranges from the values you set for the Critical thresholds. Although similar to the Pool Health report, the Pool Health History report displays the average utilization for a resource on a specific date rather than the amount of time overall the resource spent in a threshold.
Except for the Average Free Memory graph, the data points never average above the Critical threshold line (red). For the Average Free Memory graph, the data points never average below the Critical threshold line (which is at the bottom of the graph). Because this graph displays free memory, the Critical threshold is a low value, unlike the other resources.
A few points about interpreting this report:
- When the Average Usage line in the chart approaches the Average Medium Threshold (blue) line, it indicates the pool’s resource utilization is optimum regardless of the placement strategy configured.
- Resource utilization approaching the Average Low Threshold (green) is not necessarily positive. Whether Low resource utilization is positive depends on your placement strategy. For example, if your placement strategy is Maximum Density and most days the Average Usage line is at or below the green line, Workload Balancing might not be placing virtual machines as densely as possible on that pool. If so, adjust the pool’s Critical threshold values until most of its resource utilization falls into the Average Medium (blue) threshold range.
- When the Average Usage line intersects with the Average Critical Threshold Percent (red), this intersection indicates the days when the average resource utilization met or exceeded the Critical threshold value for that resource.
If you find the data points in most of your graphs are not in the Average Medium Threshold range, but you are satisfied with the performance of this pool, you might need to adjust the Critical threshold for this pool. For more information, see Changing the Critical Thresholds.
Pool optimization history
The Pool Optimization History report provides chronological visibility into the Workload Balancing optimization activity.
Optimization activity is summarized graphically and in a table. Drilling into a date field within the table displays detailed information for each pool optimization performed for that day.
This report lets you see the following information:
- VM Name: The name of the virtual machine that Workload Balancing optimized.
- Reason: The reason for the optimization.
- Status: Whether the optimization was successful.
- From Host: The physical server where the virtual machine was originally hosted.
- To Host: The physical server where the virtual machine was moved.
- Time: The time when the optimization occurred.
Tip:
You can also generate a Pool Optimization History report from the WLB tab, by clicking the View History link.
Virtual machine motion history
This line graph displays the number of times virtual machines moved on a resource pool over a period. It indicates if a move resulted from an optimization recommendation and to which host the virtual machine moved. This report also indicates the reason for the optimization. You can use this report to audit the number of moves on a pool.
Some points about interpreting this report:
- The numbers on the left side of the chart correspond with the number of moves possible, which is based on how many VMs are in a resource pool.
- You can look at details of the moves on a specific date by expanding the + sign in the Date section of the report.
Virtual Machine Performance history
This report displays performance data for each virtual machine on a specific host for a time period you specify. Workload Balancing bases the performance data on the amount of virtual resources allocated for the virtual machine. For example, if the Average CPU Usage for your VM is 67%, your VM was using, on average, 67% of its vCPU for the specified period.
The initial view of the report displays an average value for the resource utilization over the period you specified.
Expanding the + sign displays line graphs for individual resources. You can use these graphs to see trends in resource utilization over time.
This report displays data for CPU Usage, Free Memory, and Network Reads/Writes.