Please wait for the User profile Service Windows 2008 R2
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Managing Profile Service Slow Link Detection Describes how to optimize slow link detection in Windows and Windows Server. 03/19/2021 v-tappelgate v-tappelgate dcscontentpm itpro troubleshooting windows-server medium kaushika sap:user-profiles, csstroubleshoot windows-server-user-profiles ProfSvc This article describes how to optimize slow link detection to effectively balance the quality of the bandwidth estimate against the amount of time spent calculating the estimate. Applies to: Windows 11, Windows 10, Windows 8.1, Windows 8, Windows Server 2022, Windows Server 2019, Windows Server 2016, Windows Server 2012 R2, Windows Server 2012, Windows
Server 2008 R2, Windows Server 2008 Windows User Profile Service can use slow link detection to determine whether to download a roaming user profile to the client computer when the user signs in. If the service determines that the connection to the client computer is slow, the client skips the download. Instead, it loads the local copy of the roaming user profile. The service also records an event that resembles the following: Log Name: Application The user might also receive a message that resembles the following: Your roaming profile isn't synchronized with the server
because a slow network connection is detected. You've been signed in with a local profile. The default configuration of the slow link detection settings should correctly identify slow links in most deployments. However, if Windows does not seem to identify slow links correctly, consider changing the slow link detection settings. For example, if the User Profile Service determines that a network connection is a fast link, but in reality the connection is slow, the
user sign-in experience might be unusually slow. The user might see the "Waiting for the User Profile Service" message for an unacceptably long time. The following sections describe how the slow link detection algorithm works, and recommend a starting point and factors to consider in your own testing and tuning. When slow link detection is enabled, the User Profile Service uses
a temporary file on the server to do a set of file writes and reads. To calculate the link speed and delay during these operations, the service uses statistics that are measured by the Network Location Awareness (NLA) service. The size of the temporary file is specified by the PingBufferSize registry entry. This entry is defined as follows:
The quality of the estimate depends on the PingBufferSize value and how well the metrics of the algorithm match the actual transfer patterns and network topology. How slow link detection works in older operating systemsFor Windows Server 2016 and earlier versions, and Windows 10, version 1803 and earlier versions, the maximum value of PingBufferSize is 65536. During the link test, the service writes PingBufferSize + 200 bytes of data, and then measures the statistics. This algorithm doesn't provide an estimate that's sufficiently refined to effectively identify slow links. It can produce false positives (a connection is labeled as a slow link despite being fast enough) or false negatives (a connection isn't labeled as a slow link despite being slow). How slow link detection works in current operating systemsThe slow link detection process has changed in Windows Server 2019 and Windows 10, version 1809 and later versions. Additionally, the maximum PingBufferSize value has increased to 4194304. The changes are available in the following updates:
The new algorithm uses a different file access pattern. Instead of writing data one time and then measuring, the new algorithm uses a combination of writing and reading, as follows:
This algorithm produces more accurate delay and throughput measurements. The new maximum PingBufferSize value provides more flexibility. However, if the link is very slow, a large PingBufferSize value might slow down the algorithm itself so that it delays the whole process of downloading the user profile. Settings that control slow link detectionWindows provides several Group Policy settings that control slow link detection. The following table describes some of the most important of these policies. For more information about how to use these policies, see Policy CSP - ADMX_UserProfiles: ADMX_UserProfiles/SlowLinkTimeOut.
Testing the factors that affect profile download speed for your deploymentTo optimize user profile downloads for your environment, you have to balance the following factors:
The following values are the defaults for the policy and registry settings.
We've tested slow link detection by using < 10-Mbit/s broadband links plus VPN, Wi-Fi networks, and LAN connections. This testing shows that a PingBufferSize of 1,048,576 (1 MB) provides a balance between correctly identifying slow links and delaying the link detection process. We recommend that you use this value to start testing. Depending on your environment, the actual value that you should use might be lower or higher. To make sure that slow link detection works reliably under various conditions, test several combinations of profiles (both full and incremental sync) and network conditions. Network factors to consider
User profile factors to considerWhen the user signs in to Windows, the User Profile Service enumerates all the files in the user profile to determine what to update on the local copy. This update might involve downloading a few files that have changed (an incremental update) or downloading the entire user profile (full sync). When the user signs out, Windows uploads any profile files that have changed. This transaction resembles an incremental update. For testing, consider the time that's required to download the entire user profile, especially the largest profile that you have. Because the User Profile Service enumerates the files, the "size" of a profile depends on both the number of files and the total amount of data in those files. Make sure that the user sign-in experience meets the SLA even when doing a full download of the largest profile. Tuning the user profilesYou can improve the sign-in experience over slow links by configuring the user profiles as follows:
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