System Details - VM Test
This test collects various metrics pertaining to the CPU and memory usage of every processor supported by a guest. The details of this test are as follows:
Target of the test : A Hyper-V / Hyper-V VDI server
Agent executing the test : An internal agent
Output of the test : For a Hyper-V server, one set of results for every processor on each VM and
For a Hyper-V VDI server, one set of results for every processor used by the user who is currently logged into each VM
First-level descriptor: VM name or User on VM
Second-level descriptor: Processor name
|
Measurement | Description | Measurement Unit | Interpretation |
---|---|---|---|
Virtual CPU utilization |
This measurement indicates the percentage of CPU utilized by the processor. |
Percent |
A high value could signify a CPU bottleneck. The CPU utilization may be high because a few processes are consuming a lot of CPU, or because there are too many processes contending for a limited resource. The detailed diagnosis of this test reveals the top-10 CPU-intensive processes on the guest. |
System usage of virtual CPU |
Indicates the percentage of CPU time spent for system-level processing. |
Percent |
An unusually high value indicates a problem and may be due to too many system-level tasks executing simultaneously. |
Run queue in VM |
Indicates the instantaneous length of the queue in which threads are waiting for the processor cycle. This length does not include the threads that are currently being executed. |
Number |
A value consistently greater than 2 indicates that many processes could be simultaneously contending for the processor. |
Blocked processes in VM |
Indicates the number of processes blocked for I/O, paging, etc. |
Number |
A high value could indicate an I/O problem on the guest (e.g., a slow disk). |
Swap memory in VM |
Denotes the committed amount of virtual memory. This corresponds to the space reserved for virtual memory on disk paging file(s). |
MB |
An unusually high value for the swap usage can indicate a memory bottleneck. Check the memory utilization of individual processes to figure out the process(es) that has (have) maximum memory consumption and look to tune their memory usages and allocations accordingly. |
Free memory in VM |
Indicates the free memory available. |
MB |
This measure typically indicates the amount of memory available for use by applications running on the target VM. On Unix operating systems (AIX and Linux), the operating system tends to use parts of the available memory for caching files, objects, etc. When applications require additional memory, this is released from the operating system cache. Hence, to understand the true free memory that is available to applications, the eG agent reports the sum of the free physical memory and the operating system cache memory size as the value of the Free memory in VM measure while monitoring AIX and Linux guest operating systems. |
Scan rate in VM |
Indicates the memory scan rate. |
Pages/Sec |
A high value is indicative of memory thrashing. Excessive thrashing can be detrimental to guest performance. |
Note:
For multi-processor systems, where the CPU statistics are reported for each processor on the system, the statistics that are system-specific (e.g., run queue length, free memory, etc.) are only reported for the "Summary" descriptor of this test.
The detailed diagnosis capability of the Virtual CPU utilization measure, if enabled, provides a listing of the top 10 CPU-consuming processes (see Figure 8). In the event of a Cpu bottleneck, this information will enable users to identify the processes consuming a high percentage of CPU time. The users may then decide to stop such processes, so as to release the CPU resource for more important processing purposes.
Figure 8 : The top 10 CPU consuming processes
Note:
While instantaneous spikes in CPU utilization are captured by the eG agents and displayed in the Measures page, the detailed diagnosis will not capture/display such instantaneous spikes. Instead, detailed diagnosis will display only a consistent increase in CPU utilization observed over a period of time.