Problems with Hyper-V on Server 2019 (1809) after August 2020 patches

Cannon, Chris 121

We've been having problems after installing August 2020 Patches on our 2019 HyperV hosts. We have multiple hyper-v clusters across Dell VRTX and UCS blades w/ ISCSI backend SANS. Both environments have seen backup times double. Additionally loading a VMs settings in HyperV or Failover cluster manager is taking a very long time. We are not using a 3rd party AV but defender managed by SCCM. Usually when i see issues like this it feels like a storage performance issue but i'm seeing the issue across the board with iscsi as well as direct attached.

Patches applied
KB4566424
KB4565349
KB4569776

our change log indicates no other changes. Our hyperv hosts have no other roles.

I'm going to try roll back the august patching and do a quick A/B test to see if that remediates the issue, but thought i'd post to see if anyone else has seen this issue.

Chris

Daniel Zhou (Shanghai Wicresoft Co,.Ltd.) 256 Reputation points

2020-09-04T07:23:51.51+00:00

Hi，

Yes, you can roll back to the previous version to see if the question still exists. And you can update your result here.

And if anyone has the same issue, welcome to post your question here.

Best Regards,
Daniel
Cannon, Chris 121 Reputation points

2020-09-04T14:58:07.043+00:00

I removed only KB4565349 from a 5 node cluster (150 vms) on UCS blade chasssis and from a smaller 2 node cluster (dell vrtx) with around a dozen VMs. With the larger cluster, i was previously waiting on the window to open for a VM settings from FCM was taking between 20-40 seconds. I'm loading them now between 3 - 5. I do not yet have statistics on backups; I had to pause backups on the larger cluster b/c the job was running past the maintenance window. I'm re-enabling that back up now. With the smaller cluster, i made the change after backups had completed so i don't have a comparison.

With it being a longer holiday weekend i'll likely let things sit as they are over the weekend. If backups seem back to normal, i'm open to do some more testing with a couple other clusters (brand new UCS blades). To my knowledge, we're not seeing any VM performance issues at this point.

Thanks Chris
Daniel Zhou (Shanghai Wicresoft Co,.Ltd.) 256 Reputation points

2020-09-07T01:52:19.217+00:00

Sounds good.

Please let me know if you have any other questions.
Paul Webb 26 Reputation points

2020-11-12T06:30:17.36+00:00

We are also seeing delays on our 2019 Cluster. This manifests in slow "Get-VM" commands on the nodes and slowness opening settings for any of the VMs. It also seems to be causing delayed stats coming into Veeam One - sometimes these can be 15 minutes behind.

I don't like the idea of uninstalling updates to fix the issue - essentially if Microsoft is aware of the issue, they need to fix it! It could also affect anyone that has ISO compliance requiring fixes to be applied within a particular time window.

Does anyone have a link or reference to the Hotfix (Hotfix ID?) which solves the issue? I don't mind opening a case with Microsoft, if I need to go down that route to receive the fix, but it will be quicker if I can point them in the right direction.
Alessio P 66 Reputation points

2020-11-12T06:35:09.667+00:00

I don't think there is a public hotfix yet, only a private hotfix created ad hoc. You'll have to wait for a general release.
Alex
Cannon, Chris 121 Reputation points

2020-11-12T11:55:23.927+00:00

I'm not sure i feel comfortable sharing the hotfix MS provided me as i'm not sure it was anywhere close to a finished product. I should add that I am not comfortable putting this on any of our production 2019 Hyper V servers.; I'm waiting on the general release.
Paul Webb 26 Reputation points

2020-11-13T10:09:23.627+00:00

Hi Chris
I just looked at all the hotfixes and updates. Do you know which one you uninstalled on your test environment to get things back to speed?

Source Description HotFixID InstalledBy InstalledOn

NODE Update KB4580422 24/10/2020 00:00:00
NODE Security Update KB4470788 12/03/2019 00:00:00
NODE Update KB4494174 11/05/2020 00:00:00
NODE Security Update KB4549947 NT AUTHORITY\SYSTEM 11/05/2020 00:00:00
NODE Security Update KB4570332 NT AUTHORITY\SYSTEM 24/10/2020 00:00:00
NODE Security Update KB4577667 NT AUTHORITY\SYSTEM 24/10/2020 00:00:00
NODE Security Update KB4577668 NT AUTHORITY\SYSTEM 24/10/2020 00:00:00

Cheers
Paul Webb 26 Reputation points

2020-11-13T10:27:03.567+00:00

Notice there is a new CU released ....
2020-11 Cumulative Update for Windows Server 2019 (1809) for x64-based Systems (KB4586793) released Nov 11.
Tayschrenn 6 Reputation points

2020-11-23T15:11:51.463+00:00

This is certainly happening on clusters we run. We have not yet rolled back (more complicated than removing a single update) and inherently puts our environment in risk by running on an old rollup if we do.

Very frustrating to not have Microsoft already patched this, so we'll likely burn a support case to get a hotfix.

Can you provide any estimate on resolution or acknowledgment that Microsoft has even identified this?
Cannon, Chris 121 Reputation points

2020-11-23T15:41:20.103+00:00

Its been a month since i've heard from them. I pinged them a moment ago to see if there is a schedule for it to be included in the normal rollup. Believe me... I share your frustration. It took several calls/screen shares with multiple teams to get anyone to really acknowledge the issue. I'm still waiting on it to be rolled into the monthly cumulative. I'll respond if i hear back.

Chris
Cannon, Chris 121 Reputation points

2020-11-23T15:43:59.977+00:00

I just heard back. The update is scheduled for inclusion in January.
Tayschrenn 6 Reputation points

2020-11-23T16:19:23.44+00:00

I appreciate you taking the time to update the thread - hopefully it helps others as well.
Daniel Walker 1 Reputation point

2020-11-24T21:08:22.617+00:00

Any chance you can share the hotfix ID (even if you aren't sharing the hotfix) so we can request it via our cases?
Cannon, Chris 121 Reputation points

2020-11-24T21:25:35.513+00:00

The exe has KB900644.
Brendon Holt 16 Reputation points

2020-11-30T10:51:24.997+00:00

Add us to the mix, this weekend (Thanksgiving) we decided to update the Hardware Platform. Installation of Server 2019 went fine and updates were applied, up until November.

We experienced VERY SLOW Hyper-V Manager to Create or to Manage Settings on the Two New Super Powerful Computers just installed. Testing showed that during Hyper-V Manager could slow Guests down so much login to RDS servers was slow/failed. Was just taking forever to work in settings. Sunday we re-installed 2019 Server on one Machine and it was fine until updates were applied.

We decided to apply updates and deal with this issue because we provide this platform to end users, and the Legal/Financial Liability from Zero Net Logon outweighs the speed of IT Management. NOTE WE CANNOT WORK IN HYPER-V MANAGER IN PRODUCTION HOURS, 11PM to 2AM.

This BUG NEEDS TO BE FIXED and it is a SEVERE LIMITATION. I understand we all work in a complex and dangerous world, but hopefully we get a Fix SOON for this issue.
Jens Klarskov Jensen 1 Reputation point

2021-01-14T11:20:42.117+00:00
On a 6 Nodes Win2019 SCVMM managed FailOverCluster, that we use for Automated Testing , which heavily relies on CheckPoints we have these findings:

Win2019/SCVMM2019 has double duration, when operations are performed on Non SCV owner, whereas Win2016/SCVMM2016 has no measureable difference.

Win2019+KB4586793 doubles Hyper-V Restore on Non owner. SCVMM Restore is four times slowere, mostly affected by prolonged Refresh durations

Win2019+KB4598230 adds 30% to Hyper-V Restore. Doubles SCVMM Restore duration,

Eventually MigrateVm AWAY from SCV Owner ends up lasting 6 – 14 minutes

Measurements when Restoring a complex CheckPoint (Numbers are seconds):

So January Update was even worse!
Jens Klarskov Jensen 1 Reputation point

2021-01-14T11:28:34.283+00:00

BTW: Due to lots of SCVMM Error ID 2606 From the superslow Refresh(*), we have added 'Retry' SCVMM Command' for ERRORID:2606 to our Test Automation Execution , but are still severely down on Test Thrioughput.. We are still on KB4586793!

Unable to acquire a 'Delete' lock on object '52112b4e-3c4c-42b0-a2d9-0e708231d1c5' of type 'VirtualHardDisk' because it is locked by task 'ec55c407-f8dc-4900-9f3a-ce570d4a5d02' 'Refresh host cluster' with a 'Write' lock. (Error ID: 2606)
Jens Klarskov Jensen 1 Reputation point

2021-01-14T14:37:52.13+00:00

For completeness, we changed VmDatStore.dll back to the latest available in WinSxS before August 2020, an got these numbers - so no relief compared to August, but sime relief compared to the Jan 2021 results (We have only tried this on a Staging environment!)

.
Mikkel Lund Knudsen 106 Reputation points

2021-01-15T09:49:37.533+00:00

Hello Jens.
Have you been in talk with Microsoft regarding this issue? :)
DaxtechIT 6 Reputation points

2021-01-17T19:59:04.62+00:00

We opened a ticket with MS and referenced this post and the case# CannonChris-5226 provided. We were provided a private hotfix that is time limited which they stated they have had for a few months. It was time stamped in October 2020. Installing this hotfix requires using bcdedit to put and leave the server in test mode until the patch is removed and replaced with the public version. They also make accept a bunch of warnings that the hotfix is provided as-in and may cause other issues.

Given the impact on our environment and that there were no issues encountered in our test environment we have put this into production and it immediately resolved the IO performance issue. It did not solve the issue with VM settings taking a long time to load or the right click menu in cluster manager disappearing when you try to select something.
Jens Klarskov Jensen 1 Reputation point

2021-01-19T16:30:09.727+00:00

Yes we have a ticket and our 24/7 Team received HF KB900264 to test, but it is too old.

Here are Results with Nodes rolled back from Jan 2021 CU/Nov 2020 CU and with July 2020 CU:

To Compare with:
Jens Klarskov Jensen 1 Reputation point

2021-01-19T16:35:22.277+00:00

BTW, Numbers are in Seconds and average of three on an almost idle Two node Staging/Test Cluster with Lenovo SR650 + SSD SAN with duplicated Fibers.
Cannon, Chris 121 Reputation points

2021-02-26T21:18:42.927+00:00

Quick Followup. I'm hearing this fix is set to be released in March 2021. Why the delay?.. The fix was expanded to include additional issues and got pushed until the adjacent issues got looped in. I'm hopeful again

Chris
Smith, Trevor 1 Reputation point

2021-03-30T17:28:47.787+00:00

Does anyone know if the March 2021 updates resolved the slowness issue?
Smith, Trevor 1 Reputation point

2021-03-30T17:29:03.037+00:00

Does anyone know if the March 2021 updates resolved the slowness issue?
Brendon Holt 16 Reputation points

2021-05-26T02:56:22.203+00:00

I have read this and we decided to make the update to 2021-05 Cumulative Update. Our VEEAM backups are now completed without issue at normal speeds and after a lag the first time going into settings on Hyper-V we can now open all settings quickly. 40 Seconds to 1 Minute First Time, then 1 Second after that.

I believe they have fixed this issue, at least for my environment.

Thanks to all for your persistence on this issue.

33 answers

Cannon, Chris 121 Reputation points

2020-09-28T18:34:54.517+00:00

I have an open ticket with Microsoft and i'm hoping to get some attention to the problem. Unfortunately, i seem to be the only person who has brought this up. Today, I did some testing beyond just removing and installing the patch. I believe the problem is tied to the VmDatastore.dll which was updated in August 2020.

I did some Process Monitor research and found that duration for vmms.exe file reads of any virtual machines vmcx file is nearly double of what it was previously. If you look at the stack for those reads you can see VmDataStore.dll is prominent. While the duration of those reads are tiny fractions of a second, when you consider the loading of a single VM can lead to 40,000 file reads, it addes up. When scaled to a multi-node cluster with a lot of VMs, it becomes more noticeable.

I found i can just roll back and then forward that single .dll and change the performance behavior. Powershell modules , Hyperv manager, Failover cluster manager and i suspect on host backups leverage vmms significantly. I've given MS all this info and hope it will get sent to someone who can do something about it. Maybe it will get some traction.

Chris
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Alessio P 66 Reputation points

2020-09-30T15:26:02.343+00:00

Hello Chris,
we are facing the same identical problem, we too have opened a case with Microsoft but they are still running discovery tools.
You say that rolling back that simple DLL you could workaround the problem, do you confirm it?
Do you confirm that uninstalling those patches the problem goes away too?
Is there any chance that you share your case number? This may speed up things for us!
Thanks,
Alex

Cannon, Chris 121 Reputation points

2020-09-30T16:05:17.07+00:00

I can confirm

Only removing August/Sept 2020 rollup back to July fixed it (kept other patches)

Having Sept 2020 rollup installed and rolling back the single dll fixed it

I've done all tests AOK but have not yet initiated a new backup to confirm that is also back to normal.

Alessio P 66 Reputation points

2020-09-30T16:09:40.813+00:00

our is 120083125002044
Friday we will try one of the two options and I'll let you know.
Should I wait to share you case number with Microsoft?
Thanks,Alex

Cannon, Chris 121 Reputation points

2020-09-30T16:13:56.997+00:00

Feel free to share it when you want. Both of us can likely get some more traction moving forward

You're welcome. Chris

Cannon, Chris 121 Reputation points

2020-10-02T13:02:09.593+00:00

I have reviewed 2 days of backups after Installing Sept 2020 rollup AND rollback of only VmDataStore.dll. Backup times have gone back to normal. The ticket with MS is still open

Alessio P 66 Reputation points

2020-10-02T13:08:18.797+00:00

We re still taking the long path: going back to June 16, 2020—KB4567513 (OS Build 17763.1294) on all hosts; Microsoft asked to do it as first test.
I'll let you know.
Thanks,
Alex
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Cannon, Chris 121 Reputation points

2020-10-15T11:52:09.397+00:00

I plan on updating once my ticket with MS is resolved/closed. Seems like they recognize the issue now and they're working through updating the file(s) in play. I've tested one set thusfar; I'm not sure if Alex has or not. The first set of files i received presented a different problem. There is a significant time zone difference between my tech and I so it can go a half day before i hear back.

Chris
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Alessio P 66 Reputation points

2020-10-15T11:57:10.6+00:00

We haven't received anything from Microsoft, they put the ticket in standby, waiting for a solution from the upper level... :(
I'm glad that at least they're working with you!

Alex

Jayhal 6 Reputation points

2020-10-23T08:33:32.337+00:00

Hi Chris, Alessio

We have been facing the same issue on our hyperV 2019 cluster.

Did you receive any update from MS on this? We also have a case going on with them but it very recent and not heard anything back so far.

Your response is much appreciated.

Kind Regards,
Jay

Alessio P 66 Reputation points

2020-10-23T08:37:00.463+00:00

Hi Jay, we are in your same situation, no answer from Microsoft.
Chris was in a more advanced state...
Alex

Cannon, Chris 121 Reputation points

2020-11-23T15:43:07.257+00:00

I wasn't getting very far until i provided specifics to the problem. Just heard back from my tech who indicated the update will be released in January

Brendon Holt 16 Reputation points

2020-11-30T12:32:56.31+00:00

Ouch, January. It is what it is, we live in a dangerous world in IT.
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Cannon, Chris 121 Reputation points

2020-09-08T13:37:03.403+00:00

Quick update. After the removal of KB4565349 backup times returned to normal (With the patch backups went from 4-5 hours to 11-12 hours on the cluster i'm testing against) . I can also launch Vm settings within seconds now that the patch is gone. Are there known issues with this KB?

https://borncity.com/win/2020/08/14/probleme-microsoft-august-2020-patchday-nachlese/ There is a comment that leads me to believe there are others that are having the issue as well. I don't see any new comments however.

I'm seeing the issue across different hardware platforms on both datacenter and standard editions.

Chris
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Daniel Zhou (Shanghai Wicresoft Co,.Ltd.) 256 Reputation points

2020-09-09T07:22:39.433+00:00

Hi,

I haven't seen your issue in the known issue for this update.

Best Regards,
Daniel
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chriZa 21 Reputation points

2020-09-09T12:57:20.63+00:00

Same problem here - since KB4565349 backup and replication tasks are very slow.
Just installed KB4570333 on all hyper-v hosts but still backup times are doubled.
Will this be fixed in an upcoming CU or do I have to uninstall the CUs KB4570333 and KB4565349 to get back to a normal backup behavior.

Regards,
chriZa
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Cannon, Chris 121 Reputation points

2020-09-10T12:35:50.33+00:00

I too have installed Septembers KB4570333 and have found the problems have returned; assuming the problem was rolled forward. Backups times are again more than double what they were previously. I am finding that when it comes to looking at the VM settings either through FCM or Hyper-v Manager, the slowness loading settings is more prevalent on my deeper clusters. Some of my larger clusters have 120-150 VMs.

Our backups leverage on-host checkpoints so I suspect whatever problem is causing the settings and console connection slowness is also related to the backups. Smaller backups doubling in minutes isn't a huge big deal but when the big backups double, it causes a significant problem.

Daniel, is there a way to file a bug report?

Thanks

Chris
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Daniel Zhou (Shanghai Wicresoft Co,.Ltd.) 256 Reputation points

2020-09-14T01:28:09.347+00:00

Maybe you can check this:

https://www.microsoft.com/en-us/msrc/faqs-report-an-issue

Best Regards,
Daniel

Cannon, Chris 121 Reputation points

2020-09-21T20:50:20.803+00:00

Appreciate the follow up. Most those FAQs send you to the generic support page. I was able to open a ticket with MS support using our SA agreement. That was a week or so ago. At this point I've changed teams twice. I provided a pretty thorough list of noted symptoms and some of those cross a few different functional groups so i'm getting passed between teams. I'm back to the original team and i suspect that person is tier 1 or pre-tier 1. If i get some results i'll post again.

I should note to others that the problem is definitely more prevalent with larger environments. While my smaller clusters backups did increase 2x...going 15-30 minutes isn't as noticeable but with our large clusters (100+ Vms) a backup growing by 4-6 hours is terrible.

Jacques Magne 6 Reputation points

2020-09-23T08:57:14.99+00:00

Same problem also with Hyper-V hosts , too long to get vm settings on failover console.
I had to uninstall KB4570333 et KB4565349.
Ok now, but what's about next update ?

Thanks

Brendon Holt 16 Reputation points

2020-11-30T12:17:41.183+00:00

Did Microsoft actually give you a timeline when these issues would be resolved. We are very frustrated also and it is a big PIA.

Cannon, Chris 121 Reputation points

2020-11-30T12:38:54.527+00:00

They said January. Keeping my fingers crossed.

Chris
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