I've gone over that , however, there is another fix that lets you leave VMQ enabled and get it working properly (which I assume is the goal)
BUT ONE difference in my case is that the other guest VM's do not exhibit this behavior, HOWEVER, my other VM's are 2008r2 , one of which is the RDP server that gets banged on all day long without issue. ENVIRONMENT My Hyper-V hosts are Dell PowerEdge R520, utilizing Broadcom NetXtreme 1Gb NICs and running Server 2008R2 SP2. Firmware/drivers all up to date. The issue has only ever existed on the guest VMs, never the host nor any other baremetal box. RESOLUTION There's this little thing called Virtual Machine Queues. In short, it increases overall throughput for VMs by offloading virtual network processing to the physical adapter. Read more here. Prior to stumbling across that article, I had actually stumbled upon a resolution that basically solves the issue by simply disabling VMQ on the physical adapters assigned to the VMs. But I started reading about VMQ and I wanted it! So I then found the above article and realized the problem: Broadcom has VMQ enabled by default, however, there is a registry value that needs to be added first for VMQ to function properly. Without the registry value, you get the problem of slow network performance. STEPS Since Broadcom has VMQ enabled by default, I disable it in the configuration properties of all my physical adapters assigned to my guests, in the advanced tab. Intel NIC owners need not do this step, as Intel has it disabled by default. On my Hyper-V host, I open Regedit and drill down to HKLM\SYSTEM\CurrentControlSet\Services\VMSMP\Parameters I then add to Parameters a DWORD value and name it BelowTenGigVmqEnabled (since I have a 1Gb adapter. 10Gb owners need TenGigVmqEnabled) and give it a value of 1. Finally, I go back to the physical adapters and enable Virtual Machine Queues. Instantaneously, network performance issues are solved and my pings are all <1ms. This also actually sped up the OS in my VMs and they are no longer sluggish. Queries to AD now return in a snap. My world is now beautiful. As far as I'm aware, this applies to 2012 as well. Someone else may be able to confirm that. Jean-Paul Natola From: [email protected] To: [email protected] Subject: RE: [NTSysADM] hyper-v Volume Date: Tue, 13 Jan 2015 23:32:15 +0000 Was going to suggest the same thing. Dell servers experience this issue last I checked. Jameel Sarangi VP Operations From: [email protected] [mailto:[email protected]] On Behalf Of CSSU NetAdmin Sent: Tuesday, January 13, 2015 4:08 PM To: [email protected] Subject: Re: [NTSysADM] hyper-v Volume This might not help but we had a similar problem a month ago and it turned out to be an issue with a Broadcom nic driver. We resolved it by disabling the virtual machine queue on the nics on the host. Here is the kb we followed. On Tue, Jan 13, 2015 at 4:21 PM, J- P <[email protected]> wrote: Hi all, I have a 2012r1 guest on a 2012r1 host that is a file server. long story short, the server behaves sluggish when logged on and trying to do anytjing- I have checked all the logs (both host and guest, both windows and perc logs) everything is up to date no errors . NOTE: file and folder access over the network is fine according to the users (to be fair the previous server was a single.cpu sata mirror with 4gb of ram) so it's not like they have a good baseline to compare. Anyhow , can create a new guest and attach the existing data volume from the sluggish guest AND retain the same ntfs and share permissions? tia
