AVX Support on Microsoft Windows Server 2008 R2

[pietrob71]

I'm a software developer and I have a trouble trying to run my app into my customer vmware environment, because my app need the AVX Support, but my customer vmware environment seems to haven't it.

My customer's virtualization environment is based on VMware ESXi - Version 5.5.0 Build 2068190 running on a server with 2 Intel Xeon 8 Core E5-2640V3 2.6 GHz.

As attachment, you can find a hardware analisys report produced into the virtualizated os; as you can see, if you search AVX support, into the [Standard Feature Flags] section, you can find a row with: AVX Support Not Present

Googling on the web I found this:

https://support.microsoft.com/en-us/kb/2517374

I downloaded the hotfix, but I can't run it, because I get this message: The update is not applicable to you computer.

Anyone can help me to understand how can I enable AVX Support in this virtual OS?

Thanks in advance

Pietro

[MKguy]

To rule out an issue with the GuestOS, can you just boot the VM into a live Linux image and check the following command to reliably determine whether AVX is available?

# grep -i avx /proc/cpuinfo

AVX instructions were introduced with Sandy Bridge generation CPUs, and the CPU you mentioned should support it. It's possible they have EVC enabled on a cluster with an older CPU pre-Sandy Bridge baseline where AVX and other newer instructions are masked from the Guest to enable live migration across different CPU generations.

Check the EVC mode on the cluster and what mode the VMs are running with at runtime. At the same time make sure the VM hardware version is at least 10 and upgrade if necessary. It should basically look like this in the GUI:

VMware KB: Enhanced vMotion Compatibility (EVC) processor support

You may also need to reset any custom CPU masks:

Change CPU Identification Mask Settings in the vSphere Client