Desktop’s HDX Channel Test

As already mentioned, the key factors influencing user experience in a virtual desktop infrastructure are the latencies experienced by the user while connecting to the desktop via ICA and the bandwidth used when a user interacts with a virtual desktop. High latency and excessive bandwidth consumption can often slowdown access to desktops, thereby significantly delaying subsequent user operations. Hence, monitoring the latency and bandwidth usage of the ICA communication channel between the user terminal and the virtual desktops is essential.

The Desktop’s HDX Channel test auto-discovers the virtual desktops on the Hyper-V host and the users who are currently connected to each desktop. For each such user, the test monitors the communication between a user and the virtual desktop, and reports the following:

The latency experienced by each user session;

The bandwidth used by the incoming and outgoing data/audio/multimedia traffic transacted by the ICA communication channel between each user and virtual desktop;

Using this test, an administrator can identify user sessions that are being impacted by high latency and abnormal bandwidth usage. In addition, the test also reveals the type of traffic that is causing excessive bandwidth usage, thereby providing pointers to how the client configuration can be fine-tuned in order to reduce bandwidth consumption and improve performance.

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 Microsoft Hyper-V - VDI as the Component type, set Performance as the Test type, choose this test from the disabled tests list, and click on the >> button to move the test to the enabled tests list.

Note:

This test will report metrics only if the following conditions are fulfilled:

The test is applicable to Windows VMs only.
The VMs being monitored should be managed by XenDesktop Broker.
The Virtual Desktop Agent software should have been installed on the VMs.
The ICA Session performance object should be enabled on the VMs.

Target of the test : A Hyper-V server

Agent executing the test : An internal agent

Output of the test : One set of results will be reported for every user who is connected to a virtual desktop, via ICA

Configurable parameters for the test
Test period - How often should the test be executed Host - The host for which the test is to be configured. port - The port at which the host listens. By default, this is NULL. inside view using - By default, this test communicates with every VM remotely and extracts “inside view” metrics. Therefore, by default, the inside view using flag is set to Remote connection to VM (Windows). Typically, to establish this remote connection, eG Enterprise requires that the eG agent be configured with domain administrator privileges. In high-security environments, where the IT staff might have reservations about exposing the credentials of their domain administrators, this approach to extracting “inside view” metrics might not be preferred. In such environments therefore, eG Enterprise provides administrators the option to deploy a piece of software called the eG VM Agent on every Windows VM; this VM agent allows the eG agent to collect “inside view” metrics from the Windows VMs without domain administrator rights. Refer to Configuring Windows Virtual Machines to Support theInside View Using the eG VM Agent for more details on the eG VM Agent. To ensure that the “inside view” of Windows VMs is obtained using the eG VM Agent, set the inside view using flag to eG VM Agent (Windows). Once this is done, you can set the domain, admin user, and admin password parameters to none. domain, admin user, admin password, and confirm password – By default, this test connects to each virtual guest remotely and attempts to collect “inside view” metrics. Accordingly, the inside view using flag is set to Remote connection to VM (Windows) by default. To obtain a remote connection, the test must be configured with the privileges of an administrative user to the domain within which the guests reside. The first step towards this is to specify the DOMAIN within which the virtual guests reside. The admin user and admin password will change according to the domain specification. Discussed below are the different values that the domain parameter can take, and how they impact the admin user and admin password specifications: If the VMs belong to a single domain: If the guests belong to a specific domain, then specify the name of that domain against the domain parameter. In this case, any administrative user in that domain will have remote access to all the virtual guests. Therefore, an administrator account in the given domain can be provided in the ADMIN USER field and the corresponding password in the ADMIN PASSWORD field. Confirm the password by retyping it in the CONFIRM PASSWORD text box. If the VMs belong to different domains: In this case, you might want to provide multiple domain names. If this is done, then, to access the guests in every configured domain, the test should be configured with the required user privileges; this implies that along with multiple DOMAIN names, multiple ADMIN USER names and ADMIN PASSWORDs would also have to be provided. 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. If the inside view using flag is set to ‘eG VM Agent (Windows)’: On the other hand, if the inside view using flag is set to eG VM Agent (Windows), then it implies that the inside view can be obtained without domain administrator privileges. Therefore, set the domain, admin user, and admin password parameters to none. 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.

Measurements reported by the test:

Measurement

Description

Measurement Unit

Interpretation

Session average latency

Indicates the average client latency over the lifetime of this session.

Secs

Comparing the value of this measure across users will enable administrators to quickly and accurately identify users who are experiencing higher latency when connecting to a virtual desktop.

Session deviation latency

Indicates the difference between the minimum and maximum measured latency values for this session.

Secs

Audio bandwidth output

Indicates the bandwidth used while transmitting sound/audio to this user.

Kbps

Comparing these values across users will reveal which user is sending/receiving bandwidth-intensive sound/audio files over the ICA channel.

Audio bandwidth input

Indicates the bandwidth used while receiving sound/audio from this user.

Kbps

COM bandwidth input

Indicates the bandwidth used when sending data to this user’s COM port.

Kbps

Comparing these values across users will reveal which user’s COM port is sending/receiving bandwidth-intensive data over the ICA channel.

COM bandwidth ouput

Indicates the bandwidth used when receiving data from this user’s COM port.

Kbps

Drive bandwidth input

Indicates the bandwidth used when this user performs file operations on the mapped drive on the virtual desktop.

Kbps

Comparing the values of these measures across users will reveal which user is performing bandwidth-intensive file operations over the ICA channel.

Drive bandwidth output

Indicates the bandwidth used when the virtual desktop performs file operations on the client’s drive.

Kbps

Printer bandwidth input

Indicates the bandwidth used when this user prints to a desktop printer over the ICA channel.

Kbps

Comparing the values of these measures across users will reveal which user is issuing bandwidth-intensive print commands over the ICA channel.

If bandwidth consumption is too high, you may want to consider disabling printing. Alternatively, you can avoid printing large documents over the ICA connection.

Printer bandwidth output

Indicates the bandwidth used when the desktop responds to print jobs issued by this user.

Kbps

Session bandwidth input

Indicates the bandwidth used from this user to the virtual desktop for a session

Kbps

Comparing the values of these measures across users will reveal which user and which virtual desktop is performing bandwidth-intensive operatons for a session.

Session bandwidth output

Indicates the bandwidth used from the virtual desktop to this user for a session.

Kbps

Session compression input

Indicates the compression ratio used from this user to the virtual desktop for a session.

Number

Compression reduces the size of the data that is transacted over the ICA channel.

Comparing the values of these measures across users will reveal which client has been configured with a very low and a very high compression ratio.

In the event of high bandwidth usage over an ICA channel, you can set a higher compression ratio for the corresponding client and thus reduce bandwidth consumption.

Session compression output

Indicates the compression ratio used from the virtual desktop to this user for a session.

Number

Speed screen data channel bandwidth input

Indicates the bandwidth used from this user to the virtual desktop for data channel traffic.

Kbps

Comparing the values of these measures across users will reveal which user has been transmitting/receiving bandwidth-intensive data channel traffic.

Speed screen data channel bandwidth output

Indicates the bandwidth used from virtual desktop to this user for data channel traffic.

Kbps

Speed screen multimedia acceleration bandwidth input

Indicates the bandwidth used from this user to virtual desktop for multimedia traffic.

Kbps

Comparing the values of these measures across users will reveal which user has been transmitting/receiving bandwidth-intensive multimedia traffic.

Speed screen multimedia acceleration bandwidth output

Indicates the bandwidth used from the virtual desktop to this user for multimedia traffic

Kbps

HDX media stream for flash data bandwidth input

Indicates the bandwidth used from this user to virtual desktop for flash data traffic.

Kbps

Comparing the values of these measures across users will reveal which user has been transmitting/receiving bandwidth-intensive flash data.

HDX media stream for flash data bandwidth output

Indicates the bandwidth used from the virtual desktop to this user for flash data traffic

Kbps

USB bandwidth input

Indicates the bandwidth used from this user to the virtual desktop for the USB port-related traffic.

Kbps

Comparing the values of these measures across users will reveal which user has been transmitting/receiving bandwidth-intensive USB traffic.

USB bandwidth output

Indicates the bandwidth used from the virtual desktop to this user for the USB port-related traffic.

Kbps

Input line speed

Indicates the average line speed of all the sessions of this user to the desktop.

KB/Sec

Output line speed

Indicates the average line speed of all sessions from the desktop to this user.

KB/Sec

Bandwidth usage

Indicates the percentage HDX bandwidth consumption of this user.

Percent

Compare the value of this measure across users to know which user is consuming the maximum HDX bandwidth.

User's connection quality indicator:

Indicates the connectivity of this user with the Citrix environment.

The values that this measure can report and their corresponding numeric values are discussed in the table above:

Measure Value	Numeric Value
Poor connection	1
Weak connection	2
Strong connection	3
None	4

Note:

By default, this measure reports the Measure Values listed in the table above. In the graph of this measure however, the value of this measure is represented using their numeric equivalents only.

By default, Citrix recommends a standard computation of user’s connection quality indicator as mentioned in the table below:

Connection Quality Indicator	How is the Connection Quality Indicator calculated?
Weak	Reported when Bandwidth > 1MBPs Latency <= 150ms ICA RTT <= 180ms
Strong	Reported when Bandwidth > 8 MBPs Latency <= 150ms ICA RTT <= 180ms
None	Reported when Bandwidth <= 0 MBPs Latency < 0 ICA RTT < 0
Poor	Reported when any condition other than the above is noticed.