HDX Channel from Desktop Test

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 HDX Channel from Desktop test auto-discovers the virtual desktops on the ESX 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 over 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 VMware vSphere 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 : An ESX server host

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.

ESX User and ESX Password

In order to enable the test to extract the desired metrics from a target ESX server, you need to configure the test with an ESX USER and ESX PASSWORD. The user credentials to be passed here depend upon the mechanism used by the eG agent for auto-discovering the VMs on the target vSphere server and monitoring the server and its VMs. These discovery/monitoring methodologies and their corresponding configuration requirements have been discussed hereunder:

  • Discovering and monitoring by directly connecting to the target vSphere server: Starting with ESX server 3.0, a VMware ESX server offers a web service interface using which the eG agent discovers the guest operating systems on a physical ESX host. The VMware VI SDK is used by the agent to implement the web services interface. To use this interface for discovering the VMs and for monitoring, the eG agent should directly connect to the monitored vSphere/ESX server as an ESX USER with root privileges. However, if, owing to security constraints, you cannot use root user permissions, you can alternatively configure the tests with the credentials of a user who has been assigned the following permissions:

    • Diagnostics

    • TerminateSession

    To see how you can create such a user on the ESX server, refer to theCreating a Special Role on an ESX Server and Assigning the Role to a New User topic

  • Discovering and monitoring using vCenter: By default, the eG agent connects to each ESX server and discovers the VMs executing on it. While this approach scales well, it requires additional configuration for each server being monitored. For example, separate user accounts may need to be created on each server for accessing VM details. While monitoring large virtualized installations however, the agents can be optionally configured to perform guest discovery using the VM information already available in vCenter. The same vCenter can also be used to monitor the vSphere server and its VMs. In this case therefore, the ESX USER and ESX PASSWORD that you specify should be that of an Administrator or Virtual Machine Administrator in vCenter. However, if, owing to security constraints, you prefer not to use the credentials of such users, then, you can create a special role on vCenter with the following privileges:

    • Diagnostics

    • Change settings

    • View and stop sessions

    To know how to grant the above-mentioned permissions to a vCenter user, refer to Creating a Special Role on vCenter and Assigning the Role to a New User .

    If the ESX server for which this test is being configured had been discovered via vCenter, then the eG manager automatically populates the ESX USERand ESX PASSWORD text boxes with the vCenter user credentials using which the ESX discovery was performed.

Confirm Password

Confirm the specified ESX PASSWORD by retyping it here.

SSL

By default, the ESX server is SSL-enabled. Accordingly, the SSL flag is set to Yes by default. This indicates that the eG agent will communicate with the ESX server via HTTPS by default. On the other hand, if the eG agent has been configured to use the VMPerl API or CLI for monitoring (i.e., if the ESX USER parameter is set to none), then the status of the SSL flag is irrelevant.

Like the ESX sever, the vCenter is also SSL-enabled by default. If you have chosen to use the vCenter for monitoring all the ESX servers in your environment, then you have to set the SSL flag to Yes.

Webport

By default, in most virtualized environments, the ESX server and vCenter listen on port 80 (if not SSL-enabled) or on port 443 (if SSL-enabled). This implies that while monitoring an SSL-enabled ESX server directly, the eG agent, by default, connects to port 443 of the ESX server to pull out metrics, and while monitoring a non-SSL-enabled ESX server, the eG agent connects to port 80. Similarly, while monitoring an ESX server via an SSL-enabled vCenter, the eG agent connects to port 443 of vCenter to pull out the metrics, and while monitoring via a non-SSL-enabled vCenter, the eG agent connects to port 80 of vCenter. 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 ESX server or vCenter in your environment listens so that the eG agent communicates with that port.

Virtual Center

If the eG manager had discovered the target ESX server by connecting to vCenter, then the IP address of the vCenter server used for discovering this ESX server would be automatically displayed against the VIRTUAL CENTER parameter; similarly, the ESX USER and ESX PASSWORD text boxes will be automatically populated with the vCenter user credentials, using which ESX discovery was performed.

If this ESX server has not been discovered using vCenter, but you still want to discover the guests on the ESX server via vCenter, then select the IP address of the vCenter host that you wish to use for guest discovery from the VIRTUAL CENTER list. By default, this list is populated with the IP address of all vCenter hosts that were added to the eG Enterprise system at the time of discovery. Upon selection, the ESX USERand ESX PASSWORD that were pre-configured for that vCenter server will be automatically displayed against the respective text boxes.

On the other hand, if the IP address of the vCenter server of interest to you is not available in the list, then, you can add the details of the vCenter server on-the-fly, by selecting the Other option from the VIRTUAL CENTER list. This will invoke the ADD VCENTER SERVER DETAILS page. Refer to Adding the Details of a vCenter Server for VM Discoverysection to know how to add a vCenter server using this page. Once the vCenter server is added, its IP address, ESX USER, and ESX PASSWORD will be displayed against the corresponding text boxes.

On the other hand, if you want the eG agent to behave in the default manner -i.e., communicate with each ESX server for monitoring and VM information - then set the VIRTUAL CENTER parameter to ‘none’.

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.

Exclude IP

Typically, when performing VM discovery, the eG agent automatically discovers the operating system on which every VM runs, and all the IP addresses that each VM supports. If two are more VMs on a target vSphere server are in a VM cluster, then the eG agent will also auto-discover the cluster IP address. Since the cluster IP address is shared by all VMs in the cluster, this IP address will be in the discovery list of every VM in the cluster. In this case, if the eG agent attempts to obtain the 'inside view' of each VM in a cluster using their cluster IP address, incorrect metrics may be reported sometimes. To avoid this, you may want to instruct the eG agent to not use the cluster IP address when collecting 'inside view' metrics. For this, specify a comma-separated list of cluster IP addresses to be excluded in the EXCLUDE IP text box.

Ignore VMs Inside View

Administrators of some high security VMware 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 an ESX 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.

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.

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

This flag is set to Yes by default. The value of this flag cannot be changed. This implies that the virtual machines in VDI environments will always be identified using the login name of the user. 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 USERflag 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.

DD Frequency

Refers to the frequency with which detailed diagnosis measures are to be generated for this test. The default is 1:1. This indicates that, by default, detailed measures will be generated every time this test runs, and also every time the test detects a problem. You can modify this frequency, if you so desire. Also, if you intend to disable the detailed diagnosis capability for this test, you can do so by specifying none against DD FREQUENCY.

Detailed Diagnosis

To make diagnosis more efficient and accurate, eG Enterprise 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

Screen refresh latency - avg:

Indicates the average time interval measured at the client between the first step (user action) and the last step (graphical response displayed) of this user's session.

This measure maps to the 'ICA RTT' measure in Citrix Director.

Secs

This is a measurement of the screen lag that a user experiences while interacting with a virtual desktop.

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

Screen refresh latency - deviation

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

Secs

Ideally, the deviation in latencies over a session should be minimum so as to provide a consistent experience for the user.

Screen refresh latency - last:

Represents the client latency for the last request from a user. The latency is measured based on packets sent to and from each user during a session - this includes network delay plus virtual desktop side processing delays.

Secs

A consistently high latency may be indicative of poor user experience with the virtual desktop. Possible reasons for an increase in latency could be increased network delays, network congestion, etc. Typically, latencies will be below 5 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 operations 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

Session line speed input:

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

KB/Sec

 

Session line speed output:

Indicates the average line speed from the desktop to this user.

KB/Sec

 

Bandwidth usage of user's session:

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.

Thinwire bandwidth input:

Indicates the bandwidth used from user client to desktop for ThinWire traffic.

Kbps

Typically, ICA traffic is comprised of many small packets, as well as a some large packets. Large packets are commonly generated for initial session screen paints and printing jobs, whereas the ongoing user session is principally comprised of many small packets. For the most part, these small packets are the highest priority ICA data called Thinwire. Thinwire incorporates mouse movements and keystrokes. 

Compare the value of these measures across users to know which user’s keystrokes and mouse movements are generating bandwidth-intensive traffic.

Note:

This measure will report the value 0, if Framehawk is enabled for a user.

Thinwire bandwith output:

Indicates the bandwidth used from desktop to user client for ThinWire traffic.

Kbps

Note:

This measure will report the value 0, if Framehawk is enabled for a user.

Seamless bandwidth input:

Indicates the bandwidth used from user client to desktop for published applications that are not embedded in a session window.

Kbps

Compare the value of these measures across users to know which user is accessing bandwidth-intensive applications that are not in a session window.

Seamless bandwidth output:

Indicates the bandwidth used from desktop to user client for published applications that are not embedded in a session window.

Kbps

 

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.

A high value is desired for this measure, as it indicates faster delivery of applications to users, which in turn makes for a better user experience.  

You can compare the value of this measure with that of the Frame rate measure of a user to ascertain whether/not the Framehawk virtual channel has indeed enhanced that user’s experience with virtual desktops. If this comparison reveals that the value of this measure is higher than that of the Frame rate measure, it is a clear indicator of the effectiveness of the Framehawk virtual channel.

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 virtual desktop does not support Framehawk.

Framehawk network bandwidth:

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

KB

This is a good measure of the effectiveness of Framehawk in optimizing the bandwidth usage over the virtual delivery channel. A low value is desired for this measure.

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 virtual desktop does not support Framehawk.

Framehawk latency:

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

Secs

To judge the effectiveness of Framehawk, compare the value of this measure with that of the Client network latency measure for a Framehawk-enabled user. If the comparison reveals a lower value for this measure, it implies that Framehawk has succeeded in minimizing the latencies over the delivery channel.

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 virtual desktop 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

If the value of this measure is very low, it indicates that Framehawk has been very effective in minimizing the loss of packets that typically occur when data is transmitted or received over a channel.

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 virtual desktop does not support Framehawk.

Client network latency:

Indicates the latency experienced by this user when transmitting/receiving data over the ICA channel.

This measure maps to the 'Network RTT' measure in Citrix Director.

Secs

A low value is a sign of the good health of the ICA channel.

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.

To know what factors contributed to the connection quality of a user, use the detailed diagnosis of this measure.

Use the detailed diagnosis of the User's connection quality indicator measure to know why the quality of a user's desktop connection is poor. These detailed metrics reveal the bandwidth utilized and latency observed by the user. If a user's connection quality is poor, then these metrics will tell you why - is it abnormal bandwidth usage? poor responsiveness? or both?

Figure 1 : The detailed diagnosis of the User's connection quality indicator measure