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 Citrix Hypervisor 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 Citrix Hypervisor - 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 Citrix Hypervisor

Agent deploying the test : An internal/remote agent

Outputs of the test : One set of results for every user who is connected to a virtual desktop via ICA

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 at which the specified host listens. By default, this is NULL.

Xen User, Xen Password and Confirm Password

To enable the eG agent to connect to the XenServer API for collecting statistics of interest, this test should login to the target hypervisor as a root user. Provide the name of the root user in the Xen User text box. Root user privileges are mandatory when monitoring a XenServer 5.5 (or below). However, if you are monitoring XenServer 5.6 (or above) and you prefer not to expose the credentials of the root user, then, you have the option of configuring a user with pool-admin privileges as the Xen User. If you do not want to expose the credentials of a root/pool-admin user, then you can configure the tests with the credentials of a Xen User with Read-only privileges to the XenServer. However, if this is done, then the Xen Uptime test will not run, and the Xen CPU and Xen Memory tests will not be able to report metrics for the control domain descriptor. To avoid such an outcome, do the following before attempting to configure the eG tests with a Xen User who has Read-only privileges to the Citrix Hypervisor:

  • Modify the target hypervisor's configuration in the eG Enterprise. For this, follow the Infrastructure -> Components -> Add/Modify menu sequence, pick Citrix Hypervisor as the Component type, and click the Modify button corresponding to the target hypervisor.
  • In the MODIFY COMPONENT DETAILS page that then appears, make sure that the os is set to Xen and the Mode is set to SSH.
  • Then, in the same page, proceed to provide the User and Password of a user who has the right to connect to the XenServer console via SSH.
  • Then, click the Update button to save the changes.

Once this is done, you can configure the eG tests with the credentials of a Xen User with Read-only privileges.

The password of the specified Xen User needs to be mentioned in the Xen Password text box.

Then, confirm the Xen Password by retyping it in the Confirm Password text box.

SSL

By default, the Citrix Hypervisor is not SSL-enabled. This indicates that by default, the eG agent communicates with the target hypervisor using HTTP. Accordingly, the SSL flag is set to No by default. If you configure the target hypervisor to use SSL, then make sure that the SSL flag is set to Yes, so that the eG agent communicates with the target hypervisor using HTTPS. Note that a default SSL certificate comes bundled with every Citrix Hypervisor installation. If you want the eG agent to use this default certificate for communicating with an SSL-enabled Citrix Hypervisor, then no additional configuration is required. However, if you do not want to use the default certificate, then you can generate a self-signed certificate for use by the target hypervisor. In such a case, you need to explicitly follow the broad steps given below to enable the eG agent to communicate with the target hypervisor via HTTPS:

  • Obtain the server-certificate for the Citrix Hypervisor
  • Import the server-certificate into the local certificate store of the eG agent

For a detailed discussion on each of these steps, refer to the Troubleshooting section of this document.

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.

Ignore VMs Inside View

Administrators of some high security XenServer 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 Citrix Hypervisor 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.

Webport

By default, in most virtualized environments, the target hypervisor listens on port 80 (if not SSL-enabled) or on port 443 (if SSL-enabled). This implies that while monitoring an SSL-enabled Citrix hypervisor, the eG agent, by default, connects to port 443 of the server to pull out metrics, and while monitoring a non-SSL-enabled Citrix hypervisor, the eG agent connects to port 80. Accordingly, the webport parameter is set to 80 or 443 depending upon the status of the ssl flag.  In some environments however, the default ports 80 or 443 might not apply. In such a case, against the webport parameter, you can specify the exact port at which the target hypervisor in your environment listens so that the eG agent communicates with that port.

Report by User

While monitoring a Citrix hypervisor, the REPORT BY USER flag is set to No by default, indicating that by default, the guest operating systems on the target hypervisor are identified using the host name specified in the operating system. On the other hand, while monitoring a Citrix hypervisor-VDI, this flag is set to Yes by default; this implies that in case of the Citrix hypervisor-VDI model, by default, the desktops will be identified using the login of the user who is accessing them. 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.

Measurements of 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 input

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.

To minimize bandwidth consumption, you may want to consider disabling client audio mapping.

Audio bandwidth output

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.

If bandwidth consumption is too high, you may want to consider disabling client drive mapping on the client device. Client drive mapping allows users logged on to a virtual desktop from a client device to access their local drives transparently from the ICA session. Alternatively, you can conserve bandwidth by even refraining from accessing large files with client drive mapping over the ICA connection.

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

Clipboard bandwidth output

Indicates the bandwidth used for clipboard operations performed such as cut-and-paste, from the ICA session to this user's endpoint.

Kbps

 

 

Clipboard bandwidth input

Indicates the bandwidth used when performing clipboard operations such as cut-and-paste, from this user's endpoint to the ICA session.

Kbps

Last recorded latency

Indicates the last recorded latency of this user session.

Secs

Comparing the value of this measure across user sessions will enable administrators to quickly and accurately identify users who experienced high latencies recently.

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.

Resource shares

Indicates the total number of resource shares used by this user.

Number

By comparing the value of this measure across users, you can identify the user who is hogging the resources.

Frame rate

Indicates the rate at which frames are processed during this user session.

 

Frames/Sec

FPS is how fast your graphics card can output individual frames each second. It is the most time-tested and ideal measure of performance of a GPU. Higher the value of this measure, healthier is the GPU.

Framehawk frame rate

Indicates the rate at which frames are processed by the Framehawk virtual channel, if it is enabled for this user session.

Frames/Sec

The Framehawk virtual channel optimizes the delivery of virtual desktops and applications to users on broadband wireless connections, when high packet loss or congestion occurs.

Note:

This measure will report the value 0 if Framehawk is not enabled for a user or if the device from which the user is accessing the application does not support Framehawk.

Framehawk network bandwidth

Indicates the bandwidth consumption of this user session when the Framehawk virtual delivery channel is used.

Kbps

This measure will report the value 0 if Framehawk is not enabled for a user or if the device from which the user is accessing the application does not support Framehawk.

Framehawk latency

Indicates the latency experienced by this user session when the Framehawk virtual delivery channel is used.

Secs

This measure will report the value 0 if Framehawk is not enabled for a user or if the device from which the user is accessing the application does not support Framehawk.

Framehawk network loss

Indicates the percentage of packet loss experienced by this user session when the Framehawk virtual delivery channel is used.

Percent

This measure will report the value 0 if Framehawk is not enabled for a user or if the device from which the user is accessing the application does not support Framehawk.

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.

The detailed diagnosis of this measure reports the bandwidth utilized by each user, the latency, the protocol used to establish the session, client version, client ID etc.