RemoteFX User Experience - VM Test

Microsoft RemoteFX™ enables the delivery of a full Windows user experience to a range of client devices including rich clients, thin clients, and ultrathin clients. RemoteFX delivers a rich user experience for Virtual Desktop Infrastructure (VDI) by providing a 3D virtual adapter, intelligent codecs, and the ability to redirect USB devices in virtual machines. RemoteFX is integrated with the RDP protocol, which enables shared encryption, authentication, management, and device support. RemoteFX also delivers a rich user experience for session-based desktops and RemoteApp programs to a broad range of client devices.

If a remote user’s experience with a RemoteFX-enabled XenServer is poor, then administrators should be able to quickly figure out what is causing the quality of the UX to suffer – is it poor frame quality? or severe packet loss? or bad picture output owing to a high compression ratio? or bottleneck in TCP/UDP connectivity? The RemoteFX User Experience - VM test helps answer this question. For each remote user connecting to a RemoteFX-enabled XenServer, this test measures user experience and reports abnormalities (if any). This way, users who are experiencing a poor visual experience can be isolated and the reason for the same can be ascertained. In addition, the test points you to RemoteFX features that may have to be tweaked in order to improve overall 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 the Citrix XenServer - 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 Citrix XenServer - VDI

Agent deploying the test : An internal/remote agent

Outputs of the test : One set of results for every user logged into the target Citrix XenServer-VDI.

Configurable parameters for the test

  1. Test period - How often should the test be executed
  2. Host - The host for which the test is to be configured.
  3. port - The port at which the specified host listens. By default, this is NULL.
  4. XEN user - To enable the eG agent to connect to the XenServer API for collecting statistics of interest, this test should login to the XenServer 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 XenServer:

    • Modify the target XenServer’s configuration in the eG Enterprise system. For this, follow the Infrastructure -> Components -> Add/Modify menu sequence, pick Citrix XenServer as the Component type, and click the Modify button corresponding to the target XenServer.
    • 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.

  5. xen password - The password of the specified xen user needs to be mentioned here.
  6. confirm password - Confirm the xen password by retyping it here.
  7. ssl - By default, the Xen Server is not SSL-enabled. This indicates that by default, the eG agent communicates with the XenServer using HTTP. Accordingly, the ssl flag is set to No by default. If you configure the XenServer to use SSL, then make sure that the SSL flag is set to Yes, so that the eG agent communicates with the XenServer using HTTPS. Note that a default SSL certificate comes bundled with every XenServer installation. If you want the eG agent to use this default certificate for communicating with an SSL-enabled XenServer, 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 XenServer. In such a case, you need to explicitly follow the broad steps given below to enable the eG agent to communicate with the XenServer via HTTPS:

    • Obtain the server-certificate for the XenServer
    • 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.

  8. 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 with Windows VMs in particular, 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 the eG Agent’s Inside 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.

  9. 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. In order to obtain a remote connection, the test must be configured with user privileges that allow remote communication with the virtual guests. 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 guests do not belong to any domain (as in the case of Linux guests) : In this case, specify "none" in the DOMAIN field, and specify a local administrator account name in the ADMIN USER below.

      Prior to this, you need to ensure that the same local administrator account is available or is explicitly created on each of the virtual machines to be monitored. Then, proceed to provide the password of the ADMIN USER against ADMIN PASSWORD, and confirm the password by retyping it in the CONFIRM PASSWORD text box.

      If key-based authentication is implemented between the eG agent and the SSH daemon of a Linux guest, then, in the ADMIN USER text box, enter the name of the user whose <USER_HOME_DIR> (on that Linux guest) contains a .ssh directory with the public key file named authorized_keys. The ADMIN PASSWORD in this case will be the passphrase of the public key; the default public key file that is bundled with the eG agent takes the password eginnovations. Specify this as the ADMIN PASSWORD if you are using the default private/public key pair that is bundled with the eG agent to implement key-based authentication. On the other hand, if you are generating a new public/private key pair for this purpose, then use the passphrase that you provide while generating the pair. For the detailed procedure on Implementing Key-based Authentication refer to Troubleshooting the Failure of the eG Remote Agent to Connect to or Report Measures for Linux Guests.

    • If the guests 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)’ - In this case, the inside view can be obtained without domain administrator privileges. Therefore, set the domain, admin user, and admin password parameters to none.

  10. 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 XenServer 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.

  11. 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.
  12. 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.
  13. webport - By default, in most virtualized environments, the XenServer listens on port 80 (if not SSL-enabled) or on port 443 (if SSL-enabled). This implies that while monitoring an SSL-enabled XenServer, the eG agent, by default, connects to port 443 of the server to pull out metrics, and while monitoring a non-SSL-enabled XenServer, 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 XenServer in your environment listens so that the eG agent communicates with that port.
  14. REPORT BY USER - While monitoring a Citrix XenServer, the REPORT BY USER flag is set to No by default, indicating that by default, the guest operating systems on the XenServer are identified using the hostname specified in the operating system. On the other hand, while monitoring a Citrix XenServer - VDI, this flag is set to Yes by default; this implies that in case of the XenServer 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.

  15. 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 made by the test
Measurement Description Measurement Unit Interpretation

Average frames encoding time

Indicates the average time taken for encoding the frames of this user.

Secs

Compare the value of this measure across users to know for which user frames encoding took too long.

Encoding is a synchronous process that occurs on the server in the single-session (vGPU) scenario and on the VM in the multi-session scenario. The value of this measure should be under 33 ms. If it is under 33 ms but you still have performance issues, there may be an issue with the app or operating system you are using.

Frame quality

Indicates the quality of the output frame expressed as a percentage of the quality of the source frame for this user.

Percent

High frame rates produce a smooth representation of frames for the particular user, while low frame rates may cause rough or choppy representation of frames for the particular user. A high value is hence desired for this measure.

Compare the value of this measure across users to know which user received the poorest frame quality.

The quality loss may be due to RemoteFX, or it may be inherent to the graphics source. If RemoteFX caused the quality loss, the issue may be a lack of network or server resources to send higher-fidelity content. If server resources are causing the bottleneck, try one of the following approaches to improve performance:

  • Reduce the number of sessions per host.
  • Increase the memory and compute resources on the server.
  • Drop the resolution of the connection.

If network resources are causing the bottleneck, try one of the following approaches to improve network availability per session:

  • Reduce the number of sessions per host.
  • Use a higher-bandwidth network.
  • Drop the resolution of the connection.

If client resources are causing the bottleneck, try one of the following approaches to improve performance:

  • Install the most recent Remote Desktop client.
  • Increase memory and compute resources on the client machine.

Frames skipped due to insufficient client resources

Indicates the rate at which frames were skipped for this user due to insufficient client resources.

Frames/Sec

A low value is desired for this measure. Compare the value of this measure across users to know which user is connecting from a client sized with inadequate resources.

If this measure reports an unusually high value for a user, try one of the following approaches to improve the experience for that user:

  • Install the most recent Remote Desktop client.
  • Increase memory and compute resources on the client machine.

Frames skipped due to insufficient network resources

Indicates the rate at which frames were skipped for this user due to insufficient network resources.

Frames/Sec

A low value is desired for this measure. Compare the value of this measure across users to know which user is connecting via a network that is sized with inadequate resources.

If this measure reports an unusually high value for a user, try one of the following approaches to improve network availability for that user's sessions:

  • Reduce the number of sessions per host.
  • Use a higher-bandwidth network.
  • Drop the resolution of the connection.

Frames skipped due to insufficient server resources

Indicates the rate at which frames were skipped for this user due to insufficient server resources.

Frames/Sec

A low value is desired for this measure. Compare the value of this measure across users to know which user was unable to receive frames due to the lack of enough resources on the XenServer.

If this measure reports an unusually high value for a user, try one of the following approaches to improve the experience of that user:

  • Reduce the number of sessions per host.
  • Increase the memory and compute resources on the server.
  • Drop the resolution of the connection.

Graphics compression ratio

Indicates the ratio of the number of bytes encoded to the number of bytes input for this user.

Percent

The compression ratio typically affects the quality of the picture. Generally, the higher the compression ratio, the poorer the quality of the resulting picture. Ideally therefore, the value of this measure should be 0. You can compare the value of this measure across users to identify that user whose picture output was very poor owing to high compression.

Input frames

Indicates the number of source frames provided per second as input to the RemoteFx graphics for this user.

Frames/Sec

 

Output Frames

Indicates the number of source frames sent per second to this user as output of RemoteFx graphics.

Frames/Sec

If this value is less than that of the Input Frames measure, it means that frames are being skipped. To identify the bottleneck, use the 'Frames skipped....' measures.

A high value for any of the 'Frames skipped...' measures implies that the problem is related to the resource the counter tracks. For example, if the client does not decode and present frames at the same rate the server provides the frames, the frames skipped due to insufficient client resources will be high.

On the other hand, if the value of this measure matches that of the Input frames measure, check the value of the Average frames encoding time measure. The value of the Average frames encoding time measure should be under 33 ms. If it is under 33 ms but you still have performance issues, there may be an issue with the app or operating system you are using.

Source frames

Indicates number of frames per second composed at the source for this user.

Frames/Sec

 

Base TCP round trip time

Indicates the time between initiating a network request and receiving a response over TCP for this user.

Seconds

A high value for this measure could indicate a bottleneck in TCP connectivity between the user terminal and the server.

Base UDP round trip time

Indicates the time between initiating a network request and receiving a response over UDP for this user.

Seconds

A high value for this measure could indicate a bottleneck in UDP connectivity between the user terminal and the server.

Current TCP bandwidth

Indicates the amount of data that is currently carried from one point to another over TCP for this user.

Kbps

A consistent rise in the value of this measure could indicate that TCP traffic to/from the user is consuming bandwidth excessively. Compare the value of this measure across users to identify that user who is performing bandwidth-intensive operations on the XenServer.

Current TCP round trip time

Indicates the average time between initiating a network request and receiving a response over TCP for this user.

Seconds

A high value could indicate a current problem with TCP connectivity between the user terminal and the server.

Current UDP bandwidth

Indicates the amount of data that is currently carried from one point to another over UDP for this user.

Kbps

A consistent rise in the value of this measure could indicate that UDP traffic to/from the user is consuming bandwidth excessively. Compare the value of this measure across users to identify that user who is performing bandwidth-intensive operations on the XenServer.

Current UDP round trip time

Indicates the average time between initiating a network request and receiving a response over UDP for this user.

Secs

A high value could indicate a current problem with UDP connectivity between the user terminal and the server.

Forward error correction

Indicates the percentage of forward error corrections performed for this user.

Percent

RemoteFX UDP transport uses Forward Error Correction (FEC) to recover from the lost data packets. In the cases where such packets can be recovered, the transport doesn’t need to wait for the data to be retransmitted, which allows immediate delivery of data and prevents Head of Line Blocking. Preventing this stall results in an overall improved responsiveness.

A high value is hence desired for this measure.

Loss

Indicates the percentage of packets lost when being transmitted to this user.

Percent

A high value indicates that a large number of packets were lost without being retransmitted. By comparing the value of this measure across users, you can find that user who has suffered the maximum data loss. This could be owing to a bad network connection between the remote user terminal and the server.

Retransmissions

Indicates the percentage of packets that have been retransmitted to this user.

Percent

Retransmissions should only occur when it is certain that a packet to be retransmitted was actually lost. Redundant retransmissions can also occur because of lost acknowledgments, coarse feedback, and bad retransmissions. Retransmission rates over 5% can indicate degraded network performance on a LAN. The internet may vary between 5 and 15 percent depending upon traffic conditions. Any value above 25 percent indicates an excessive number of retransmissions that will significantly increase the time for the file transfer and annoy the user.

TCP received rate

Indicates the rate at which the data is received over TCP for this user.

Kbps

A high value is desired for these measures as it indicates high TCP throughput.

TCP sent rate

Indicates the rate at which the data is sent over TCP for this user.

Kbps

UDP received rate

Indicates the rate at which the data is received over UDP for this user.

Kbps

A high value is desired for these measures as it indicates high UDP throughput.

UDP sent rate

Indicates the rate at which the data is sent over UDP for this user.

Kbps