eG Monitoring
 

Measures reported by WVDUserLogOnTest

The process of a user logging into an AVD is fairly complex. First, the domain controller is discovered and the login credentials are authenticated. Then, the corresponding user profile is identified and loaded. Next, group policies are applied and logon scripts are processed to setup the user environment. In the meantime, additional processing may take place for a user – say, applying system profiles, creating new printers for the user, and so on. A slowdown in any of these steps can significantly delay the logon process for a user. Since logons on Windows happen sequentially, this may adversely impact the logins for other users who may be trying to access the AVD at the same time. Hence, if a user complains that he/she is unable to access an application, administrators must be able to rapidly isolate exactly where the logon process is stalling and for which user.

This test periodically monitors the user login and profile loading process and accurately identify where the process is bottlenecked. - in the authentication process? during GPO processing and if so, which GPO? which client side extension was processed by the GPO when the delay occurred? is the group policy processing mode impacting user logon?

Outputs of the test : One set of results for every user to the AVD being monitored.

The measures made by this test are as follows:

Measurement Description Measurement Unit Interpretation
Tot_sessions Indicates the number of sessions that this user has open on the AVD. Number Compare the value of this measure across users to know which user has imposed the maximum session load on the AVD.

Use the detailed diagnosis of this measure to know more details about each session; this includes, the IP address of the client from which each session is connecting, the time taken for every session to be authenticated, the session login time, and the account login time.
Logon_duration Indicates the average time taken by this user for logging in during the last measurement period. Secs If this value is abnormally high for any user, then, you can compare the time measurements reported by this test to know where exactly the user logon was bottlenecked - was it during authentication? or when processing group policies? If group processing is delaying logon, then you can compare the time metrics reported under the head Group Policy Breakup to understand where the delay occurred - was it during user discovery? Domain Controller discovery? LDAP binding? when accessing group policy object files? or when processing client-side extensions?

Use the detailed diagnosis of this measure to know which were the client side extensions processed for a user, which group policy was processed by each extension, and what is the processing time of each client side extension. In the process, you can quickly identify the client side extension that is taking an abnormally long time for processing and is probably the root-cause for the logon delay.
Avg_auth_duration Indicates the average time taken by this user login to be authenticated. Secs If the Average logon duration measure reports an abnormally high value, then compare the value of this measure with that of the Group policy processing time measure to know where the bottleneck is - in authentication? or in group policy processing?
Is_session_recon Indicates whether or not this user's session has been reconnected.   If the user's session has been reconnected, then this measure will report the value Yes. If not, then this measure will report the value No.

The numeric values that map to these measure values are as follows:
Measure Value Numeric Value
Yes 1
No 0

Note:

By default, this measure reports the above-mentioned values to indicate whether/not the user reconnected to an earlier disconnected session. In the graph of this measure however, the same is represented using the numeric equivalents i.e., 0 or 1.
GP_time Indicates the time taken for applying group policies for this user in the last measurement period. Secs Group policies impact logon performance.

If Average logon duration is abnormally high, then compare the value of this measure with that of the Average authentication duration measure to know why logon is slow - is it because of a delay in authentication? or is it owing to a group policy taking too much time to be processed?

Typically, group policies can be processed in the foreground or background. While background processing of group policies have little to no impact on logon performance, foreground group policy processing can cause logon delays. Particularly, if foreground processing is done synchronously, the user's logon experience is bound to suffer. This is because, when foreground processing is synchronous, the user is not presented with the logon prompt until computer GP processing has completed after a system boot. Likewise the user will not see their desktop at logon until user GP processing completes. This can increase startup time as seen by the user.

Other factors that can impact group policy processing time and consequently, the logon time are, user account discovery, Domain Controller discovery, LDAP discovery, and client-side extension processing. Where the logon delay can be attributed to slow group policy processing, you can compare the time metrics reported under Group Policy Breakup to isolate the source of the slowness. If say, client-side extensions are taking too long to be applied resulting in a slow logon, then use the detailed diagnosis of this measure to accurately identify the client-side extension that is taking the longest to be processed.
GP_policy Indicates the current status of the Group policy that is applied for this user.   The values reported by this measure and their corresponding numeric equivalents are described in the table below:

Measure Value Numeric Value
Success 1
Warning 2
Error 3

Note:

By default, this measure reports the above-mentioned Measure Values while indicating the current status of the Group policy. However, in the graph of this measure, the values will be represented using the corresponding numeric equivalents i.e., 1 to 3.
User_accnt_discvry Indicates the amount of time taken by this user account's information to be discovered. Secs Compare the value of this measure across users to know which user’s logon process spent maximum time in retrieving account information.
LDAP_discvry Indicates the amount of time taken by the LDAP call for this user to connect and bind to Active Directory during the last measurement period. Secs A high value for this measure signifies a delay in connecting to AD. Such delays can affect group policy processing. This is because, group policies are built on top of AD, and hence rely on the directory service's infrastructure for their operation. As a consequence, DNS and AD issues may affect Group Policies severely.

Compare the value of this measure across users to know which user’s logon process spent maximum time in connecting to Active Directory. High LDAP bind time may also affect group policy processing.
DC_discvry Indicates the time taken to discover the domain controller to be used for processing group policies for this user during the last measurement period. Secs Compare the value of this measure across users to know which user’s logon process spent maximum time in domain controller discovery.
Tot_GP_accesstime Indicates the amount of time the logon process took to access group policy object files for this user during the last measurement period. Secs Compare the value of this measure across users to know which user’s logon process spent maximum time in accessing the group policy object file.

To know which files were accessed and the time taken to access each file, use the detailed diagnosis of this measure. With the help of the detailed diagnostics, you can accurately isolate the object file that took the longest to access, and thus delayed the logon process.
CSE_apply Indicates the total number of client side extensions used for processing group policies for this user during the last measurement period. Number  
CSE_success Indicates the number of client side extensions that were successfully used for processing group policies for this user during the last measurement period. Number  
CSE_warn Indicates the number of warnings received when client side extensions were used for processing group policies for this user during the last measurement period. Number Use the detailed diagnosis of this measure to know which were the client side extensions that resulted in the generation of warning events at the time of processing. You will also know which group policies were processed by each extension.
CSE_error Indicates the number of errors registered when client side extensions were used for processing group policies for this user during the last measurement period. Number Ideally, the value of this measure should be zero. A sudden/gradual increase in the value of this measure is a cause of concern.

If a non-zero value is reported for this measure, then use the detailed diagnosis of this measure to know which client side extensions resulted in processing errors. You will also know which group policies were processed by each such extension. Moreover, the error code will also be displayed as part of detailed diagnostics, so that you can figure out what type of error occurred when processing the client side extensions.
CSE_processtime Indicates the amount of time that client side extensions took for processing group policies for this user during the last measurement period. Secs Compare the value of this measure across users to know which user's logon process spent maximum time in client side extension processing.

You can also use the detailed diagnosis of this measure to know which client side extension was used to process which group policy for a particular user. Detailed diagnostics also reveal the processing time for each client side extension. This way, you can quickly identify the client side extension that took too long to be processed and thus delayed the user logon.
Net_bandwidth Indicates the estimated network bandwidth between the VM and domain controller for this user during the last measurement period. Kbps  
Is_slow_link Indicates whether/not the network connection between the VM and domain controller is currently slow for this user.   Several components of Group Policy rely on a fast network connection. If a fast connection is unavailable between a VM and the DOC, group policy processing can be delayed. This is why, if the Group policy processing time measure reports an abnormally high value, you may want to check the value of the Is link between VM and domain controller slow? measure to determine whether the network connection between the VM and domain controller is slow.

If the network connection between the VM and domain controller is slow for a user, then this measure will report the value Yes. If it is fast, then this measure will report the value No (connection is fast).

The numeric values that correspond to the above-mentioned measure values are as follows:
Measure Value Numeric Value
Yes 1
No(connection is fast) 2

Note:

  • By default, this test reports the Measure Values listed in the table above to indicate the quality of the network link between the VM and the domain controller. In the graph of this measure however, the same is indicated using the numeric equivalents only.
  • To determine whether the network link is slow or fast, the Group Policy service compares the result of the estimated bandwidth to the slow link threshold (configured by Group Policy). A value below the threshold results in the Group Policy service flagging the network connection as a slow link. This measure reports the status of this flag only.
Background_process Indicates whether the group policy for this user is applied during foreground processing or background processing.   Foreground and background processing are key concepts in Group Policy. Foreground processing only occurs when the machine starts up or when the user logs on. Some policy areas (also called Client Side Extensions (CSEs)) can only run during foreground processing. Examples of these include Folder Redirection, Software Installation and Group Policy Preferences Drive Mapping. In contrast, background processing is that thing that occurs every 90 or so minutes on Windows workstations, where GP refreshes itself periodically. Background processing happens in the background, while the user is working and they generally never notice it. While background processing does not impact performance, foreground processing can extend start and login times.

The values that this measure can report and their corresponding numeric values are listed in the table below:
Measure Value Numeric Value
Background 1
Foreground 2

Note:

By default, this test reports the Measure Values listed in the table above to indicate when the group policy of a user was applied. In the graph of this measure however, the same is indicated using the numeric equivalents only.
Sync_process Indicates whether the group policies of this user are processed in the synchronous or asynchronous mode.   Foreground processing can operate under two different modes—synchronously or asynchronously. Asynchronous GP processing does not prevent the user from using their desktop while GP processing completes. For example, when the computer is starting up, GP asynchronous processing starts to occur for the computer, and in the meantime, the user is presented the Windows logon prompt. Likewise, for asynchronous user processing, the user logs on and is presented with their desktop while GP finishes processing. The user is not delayed getting either their logon prompt or their desktop during asynchronous GP processing. When foreground processing is synchronous, the user is not presented with the logon prompt until computer GP processing has completed after a system boot. Likewise the user will not see their desktop at logon until user GP processing completes. This can have the effect of making the user feel like the system is running slow. In short, synchronous processing can impact startup time, where asynchronous does not. Foreground processing will run synchronously for two reasons:

  • The administrator forces synchronous processing through a policy setting. This can be done by enabling the Computer ConfigurationPoliciesAdministrative TemplatesSystemLogonAlways wait for the network at computer startup and logon policy setting. Enabling this setting will make all foreground processing synchronous. This is commonly used for troubleshooting problems with Group Policy processing, but does not always get turned back off again.
  • A particular CSE requires synchronous foreground processing. There are four CSEs provided by Microsoft that currently require synchronous foreground processing: Software Installation, Folder Redirection, Microsoft Disk Quota and GP Preferences Drive Mapping. If any of these are enabled within one or more GPOs, they will trigger the next foreground processing cycle to run synchronously when they are changed.

It is therefore best to avoid synchronous CSEs and to not force synchronous policy. If usage of synchronous CSEs is necessary, minimize changes to these policy settings.

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

Measure Value Numeric Value
Synchronous 1
Asynchronous 2

Note:

By default, this test reports the Measure Values listed in the table above to indicate when the group policy of a user was applied. In the graph of this measure however, the same is indicated using the numeric equivalents only.