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Stelli1989
Contributor
Contributor

One Disk (VMDK) slow performance in Windows Server 2016 VM

Hi @ all,

I got a performance Issue on a Server 2016 VM on an ESX 6.7

There are 2 Disks configured. 1st with 70GB for the System - the 2nd with 3TB for Files.

If I copy files inside the VM to the C:\ Drive (70GB), I have copy speeds around 110MB/s (More is not possible because of the Network)

But if i copy files to the D:\ Drive (3TB), I only get 2-8MB/s.

Both disks are on the same datastore and configured the same way (same SCSI controller, Thick-Lazy etc.)

The 3 TB VMDK was copied via VMWare Converter from another ESX 6.7 (Server 2008R2 VM) to this host and just mounted to this Server 2016 VM, so that all NTFS Permissions are still available.

I don't know why the performance on this copied disk is so bad. On the old VM it works perfectly.

Please help.

Thank you

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continuum
Immortal
Immortal

> The 3 TB VMDK was copied via VMWare Converter
Please check if the 3 TB-vmdk is really using the ESXi-vmdk format.
So open the vmdk-descriptorfile with a texteditor and check the line starting with RW.
It should reference a flat.vmdk - if it references a file named *-s001.vmdk then you need to convert the VMDK to ESXi format first.
In case you ask how to read a VMDK-descriptorfile ?
Connect to ESXi with WinSCP - go to directory of the VM.
You will see a different file-listing then you will get with the Datastorebrowser.
Select the small vmdk-file - right click it and select > embedded editor.


________________________________________________
Do you need support with a VMFS recovery problem ? - send a message via skype "sanbarrow"
I do not support Workstation 16 at this time ...

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Stelli1989
Contributor
Contributor

Hi,

This is the Content of the Descriptorfile of the 3TB VMDK:

# Disk DescriptorFile

version=1

encoding="UTF-8"

CID=c80cfb36

parentCID=ffffffff

createType="vmfs"

# Extent description

RW 6442450944 VMFS "s001.xxxx.de-flat.vmdk"

# The Disk Data Base

#DDB

ddb.adapterType = "lsilogic"

ddb.deletable = "true"

ddb.geometry.biosCylinders = "387034"

ddb.geometry.biosHeads = "255"

ddb.geometry.biosSectors = "63"

ddb.geometry.cylinders = "401024"

ddb.geometry.heads = "255"

ddb.geometry.sectors = "63"

ddb.longContentID = "9c8b63ca8e3709b4ab081304c80cfb36"

ddb.uuid = "60 00 C2 9a d3 1c af af-d3 bf 60 fe 64 9a 0f 53"

ddb.virtualHWVersion = "14"

It looks similar to the 70GB one.. Is this the correct format?

Thank you in advance

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continuum
Immortal
Immortal

Is the name of the VMDK really "s001.xxxx.de" ?
Looks a bit strange !
Please attach latest vmware.log


________________________________________________
Do you need support with a VMFS recovery problem ? - send a message via skype "sanbarrow"
I do not support Workstation 16 at this time ...

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Stelli1989
Contributor
Contributor

No the Name of the vmdk is servername.domainname.de I Just changed Servername to s001 and domainname to xxxx.de

I attached the vmware.log file

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continuum
Immortal
Immortal

> Just changed Servername to s001 and domainname to xxxx.de
Why you would do that after I told you that a vmdk name containing exactly that string would be an indicator for a misconfigured virtual disk is beyond me.
Anyway - you seem to use a feature inside the guest called "Gi Jane"
The log file is full with entries for Guest: vsep: AUDIT: VFileFltPostOpCreate  which apparently slows down the VM significantly.

Check your configuration for GI Jane and disable DEBUGGING functions - see GI Thin Agent Logs

Sorry - cant help you with that function - never saw it before.


________________________________________________
Do you need support with a VMFS recovery problem ? - send a message via skype "sanbarrow"
I do not support Workstation 16 at this time ...

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Stelli1989
Contributor
Contributor

Hi Continuum,

i tried to deactivate the GI Thin Agent, but the required settings in the guest vm are not set. So the logging should be disabled.

As i mentioned the slow performance only occures on one vmdk. Others in this VM are working fine.

Do you have any other suggestions for me?

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