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 Solaris LDoms server

Agent deploying the test : An internal agent

Outputs of the test : One set of results for every combination of virtual_guest:processor; for every guest, a set of measures will be reported for the virtual_guest:Summary descriptor as well – these measures will indicate the total CPU usage across all processors supported by that guest.

Configurable parameters for the test
Parameter Description

Test period

How often should the test be executed

Host

The host for which the test is to be configured.

Port

The port number at which the specified host listens. By default, the port is NULL.

Domain

Specify the domain within which the virtual guests reside. Since the Solaris LDoms server supports only Solaris and Linux guests, this parameter should always be set to none.

Admin User

This test connects to each virtual guest and collects status and resource usage statistics from the guest. In order to do so, the test must be configured with user privileges that allow a remote connection to the virtual guest from the Solaris host. If a single user has access to all the guest domains on the Solaris server, specify the name of that user against Admin User, and specify his password against Admin Password. On the other hand, if the user credentials vary from one guest to another, then multiple Admin Users and Admin Passwords might have to be specified for every Solaris LDoms server being monitored.

To help administrators provide these user details quickly and easily, the eG administrative interface embeds a special configuration page. To access this page, simply click on the Click here hyperlink that appears just above the parameters of this test in the test configuration page. To know how to use the special page, refer to Configuring Users for VM Monitoring.

Admin Password

The password of the Admin User needs to be provided here. Here again, if multiple passwords need to be specified, then follow the procedure detailed in Configuring Users for VM Monitoring.

Confirm Password

Confirm the password by retyping it here. Here again, if multiple passwords need to be confirmed, then follow the procedure detailed in Configuring Users for VM Monitoring.

Detailed Diagnosis

To make diagnosis more efficient and accurate, the eG Enterprise suite embeds an optional detailed diagnostic capability. With this capability, the eG agents can be configured to run detailed, more elaborate tests as and when specific problems are detected. To enable the detailed diagnosis capability of this test for a particular server, choose the On option. To disable the capability, click on the Off option.

The option to selectively enable/disable the detailed diagnosis capability will be available only if the following conditions are fulfilled:

  • The eG manager license should allow the detailed diagnosis capability
  • Both the normal and abnormal frequencies configured for the detailed diagnosis measures should not be 0.
Measurements made by the test
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.

In case of guest domains that support multiple processors, this measure will be available only for the ‘Summary’ descriptor.

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).

In case of guest domains that support multiple processors, this measure will be available only for the ‘Summary’ descriptor.

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.

In case of guest domains that support multiple processors, this measure will be available only for the ‘Summary’ descriptor.

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.   

In case of guest domains that support multiple processors, this measure will be available only for the ‘Summary’ descriptor.

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.

In case of guest domains that support multiple processors, this measure will be available only for the ‘Summary’ descriptor.

The detailed diagnosis capability of the Virtual CPU utilization measure, if enabled, provides a listing of the top 10 CPU-consuming processes (see Figure 1). 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.

systemguesttestDD-final

Figure 1 : 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.