FSLogix profile mount takes long time

Question

Hi,

I faced a very strange issue with AVD FSLogix since friday last week. The following lines are in the log:

[15:30:27.598][tid:00001164.00002e50][INFO]             Attached vhd(x) successfully
[15:30:27.598][tid:00001164.00002e50][INFO]             VHD(x) attach request returning after 281 milliseconds
[15:30:27.598][tid:00001164.00002e50][INFO]             VHD(x) attached: \\<storage>.file.core.windows.net\profiles\<path>\profile_user.VHDX
[15:30:27.598][tid:00001164.00001168][INFO]             Volume attach event
[15:30:27.598][tid:00001164.00002e50][INFO]             VHD(x) GetVirtualDiskPhysicalPath request returning after 0 milliseconds
[15:30:27.598][tid:00001164.00002e50][INFO]             VHD(x) FindFirstVolume request returning after 0 milliseconds
[15:41:00.378][tid:00001164.00002e50][INFO]             VHD(x) loop through volumes returning after 632782 milliseconds, volumes tested: 3
[15:41:00.378][tid:00001164.00002e50][INFO]             VHD(x) getVolumeGUIDFromPhysicalPath request returning after 632782 milliseconds
[15:41:00.378][tid:00001164.00002e50][INFO]             VHD(x) volume online request returning after 0 milliseconds
[15:41:00.378][tid:00001164.00002e50][INFO]             VHD(x) waitForVolumeMount request returning after 632782 milliseconds
[15:41:00.378][tid:00001164.00002e50][INFO]             VHD(x) Mounted: 
\\<storage>.file.core.windows.net\profiles\<path>\profile_user.VHDX
, VolumeName: \\?\Volume{50836ea1-ba1d-4283-af4f-16e2f58c84ab}\
[15:41:00.378][tid:00001164.00002e50][INFO]             DiskContext::mount returning after 633125 milliseconds

Check the time of waitForVolumeMount with value 632782, which means that attaching the VHDX profile storage takes 10 minutes.

I tried creating new storage. No host. No change.

FSLogix version is the latest one, and we have another AVD environment, where we have no issues.

Any idea?

Thanks!

Gabor

Answer 1

@Gabor Varga I'm glad that you were able to resolve your issue and thank you for posting your solution so that others experiencing the same thing can easily reference this!

Since the Microsoft Q&A community has a policy that "The question author cannot accept their own answer. They can only accept answers by others ", I'll repost your solution in case you'd like to "Accept " the answer. Accepted answers show up at the top, resulting in improved discoverability for others.

Issue: FSLogix profile mount takes a long time. Checked the time of waitForVolumeMount with value 632782, which meant that attaching the VHDX profile storage takes 10 minutes.

Cause: The issue was not related to AVD or FSLogix. It was caused by an on-prem DLP tool reinstallation, which was scanning the profile VHDX files during every login.

Solution: After the DLP policy was changed to skip these profile VHDX files, the issue was gone.

If your issue remains unresolved or have further questions, please let us know in the comments how we can assist. We are here to help you and strive to make your experience better and greatly value your feedback.

Answer 2

Hello there,

This looks like a performance issue with the storage location or the VM itself. This is a standard Windows API call for FindFile and isn't anything special FSLogix is doing in code.

It could be that you don't have enough IOPS in the file share to service all users. Can you ever reproduce it during off-peak times like the weekend or the night? If not then that is a good indication.

https://learn.microsoft.com/en-us/answers/questions/1127037/avd-fslogix-slow-login-diskcontext-find-returning

Hope this resolves your Query !!

--If the reply is helpful, please Upvote and Accept it as an answer--

Answer 3

Hi,

So the issue was not related to AVD or FSLogix. It was caused by an on-prem DLP tool reinstallation, which was scanning the profile VHDX files during every login.

After the DLP policy was changed to skip these files, the issue was gone.

Thanks!

Gabor