Page File - OS Test

When the load imposed by applications and services running on a server nears the amount of installed RAM, additional storage is necessary. The page file serves as the temporary store on disk for memory that cannot be accommodated in the physical RAM. Since it is frequently accessed for storing and retrieving data that is needed for virtual memory access by application, the location and sizing of the page files can have a critical impact on server's performance. Ideally, the server operating system and the page file should be available on different drives for optimal performance. Splitting the page file across different drives can improve performance further.

A rule of thumb in sizing the page file is to set the maximum size of the page file to 1.5 times the available RAM. While this works well for systems with smaller physical memory, for other systems, the optimal page file size has to be determined based on experience using the system and studying the typical workload.

This test tracks the usage of each of the page files on a Windows VM. Note that this test is available for VMs running on Windows servers only.

This test is disabled by default. To enable the test, go to the enable / disable tests page using the menu sequence : Agents -> Tests -> Enable/Disable, pick Hyper-V / Hyper-V VDI as the desired Component type, set Performance as the Test type, choose the test from the disabled tests list, and click on the < button to move the test to the ENABLED TESTS list. Finally, click the Update button.

Target of the test : A Hyper-V / Hyper-V VDI server

Agent executing the test : An internal agent

Output of the test : One set of results for every page file on a Windows server

Configurable parameters for the test
Parameter	Description
Test period	This indicates how often should the test be executed.
Host	Specify the HOST for which this test is to be configured.
Port	Specify the port at which the target host is listening. By default, this is NULL
Inside View Using	By default, this test obtains the “inside view” of VMs using the eG VM Agent. Accordingly, the Inside view using flag is set to eG VM Agent by default. The eG VM Agent is a piece of software, which should be installed on every VM on a hypervisor. Every time the eG agent runs this test, it uses the eG VM Agent to pull relevant 'inside view' metrics from each VM. Once the metrics are collected, the eG agent then communicates with each VM agent and pulls these metrics, without requiring administrator privileges. Refer to Configuring the Remote Agent to Obtain the Inside View of VMs for more details on the eG VM Agent.
Domain, Admin User, and Admin Password, and Confirm Password	By default, these parameters are set to none. This is because, by default, the eG agent collects 'inside view' metrics using the eG VM agent on each VM. Domain administrator privileges need not be granted to the eG agent if it uses this default approach to obtain the 'inside view' of Windows VMs.
Report By User	For the Hyper-V monitoring model, the Report By User flag is set to No by default, indicating that by default, the guest operating systems on the Hyper-V server are identified using the hostname specified in the operating system. On the other hand, for the Hyper-V VDI model, this flag is set to Yes by default; this implies that in case of VDI servers, by default, the guests will be identified using the login of the user who is accessing the guest OS. In other words, in VDI environments, this test will, by default, report measures for every username_on_virtualmachinename.
Report Powered OS	This flag becomes relevant only if the report by user flag is set to ‘Yes’. If the Report Powered OS flag is set to Yes (which is the default setting), then this test will report measures for even those VMs that do not have any users logged in currently. Such guests will be identified by their virtualmachine name and not by the username_on_virtualmachinename. On the other hand, if the Report Powered OS flag is set to No, then this test will not report measures for those VMs to which no users are logged in currently.
Ignore VMs Inside View	Administrators of some high security Hyper-V environments might not have permissions to internally monitor one/more VMs. The eG agent can be configured to not obtain the 'inside view' of such ‘inaccessible’ VMs using the Ignore VMs Inside View parameter. Against this parameter, you can provide a comma-separated list of VM names, or VM name patterns, for which the inside view need not be obtained. For instance, your Ignore VMs Inside View specification can be: xp,lin,win,vista. Here, the * (asterisk) is used to denote leading and trailing spaces (as the case may be). By default, this parameter is set to none indicating that the eG agent obtains the inside view of all VMs on a Hyper-V host by default. Note: While performing VM discovery, the eG agent will not discover the operating system of the VMs configured in the Ignore VMs Inside View text box.
Exclude VMs	Administrators of some virtualized environments may not want to monitor some of their less-critical VMs - for instance, VM templates - both from 'outside' and from 'inside'. The eG agent in this case can be configured to completely exclude such VMs from its monitoring purview. To achieve this, provide a comma-separated list of VMs to be excluded from monitoring in the Exclude VMs text box. Instead of VMs, VM name patterns can also be provided here in a comma-separated list. For example, your Exclude VMs specification can be: xp,lin,win,vista. Here, the * (asterisk) is used to denote leading and trailing spaces (as the case may be). By default, this parameter is set to none indicating that the eG agent obtains the inside and outside views of all VMs on a virtual host by default. By providing a comma-separated list of VMs/VM name patterns in the Exclude VMs text box, you can make sure the eG agent stops collecting 'inside' and 'outside' view metrics for a configured set of VMs.
Ignore WINNT	By default, the eG agent does not support the inside view for VMs executing on Windows NT operating systems. Accordingly, the Ignore WINNT flag is set to Yes by default.
Report Total	Set this flag to Yes if you want the test to report total page file usage - i.e., the aggregate usage across multiple page files. In this case therefore, a Total descriptor will newly appear for this test in the eG monitoring console.
Report Total only	If both the Report Total and Report Total only flags are set to Yes, then the test will report only the aggregate usage across multiple page files - in other words, the test will report values for the Total descriptor only. Likewise, if the Report Total flag is set to No, and the Report Total only flag is set to Yes, then again, the test will report current usage for the Total descriptor only. However, if both the Report Total and Report Total only flags are set to No, then the test will report individual usages only. Also, if the Report Total flag is set to Yes and theReport Total only flag is set to No, then both the individual and Total usages will be reported.

Measurements made by the test
Measurement	Description	Measurement Unit	Interpretation
Current usage	Indicates the current usage of a page file.	Percent	This metric should be less than 90%. If the page file does not have additional space, additional users/processes cannot be supported and system performance will suffer. To improve performance, consider resizing the page file. Microsoft Windows allows a minimum and maximum size of the page file to be specified. If the system has sufficient disk space, consider setting the page file to start out at the maximum size (by using the same value for the minimum and maximum sizes), so that system resources are not spent growing the page file size when there is a virtual memory shortage.