Hyper-V network performance issues with Broadcom drivers

I have seen various issues regarding certain Broadcom drivers, and Hyper-V on HP/ Dell servers.  A ping time between VMs on the same host can be 60-100ms and file copies painfully slow.

The advice is to disable the VMQ features.

get-netadaptervmq
Show all network adapters, look for the column “Enabled”

disable-netadaptervmq -name <adaptername>
Disable VMQ for specific network interface

disable-netadaptervmq *
Disable VMQ on all network interfaces

http://blog.osmicro.org/hyper-v-virtual-machine-very-slow-network-vmq/

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Unable to start Hyper-V VM “Not enough memory in the system” error

I found I was getting this in my test lab even though there was enough RAM spare on the host (approx 75% utilised only) turns out that Hyper-V is reserving a fair chunk of RAM automatically for the operating system (Server 2012 R2 in my case) therefore I just needed to lower the minimum reserve value.

Regedit – HKLM / Software / Microsoft / Windows NT / CurrentVersion / Virtualization

Create new DWORD “MemoryReserve” with value Decimal 512 to ensure minimum 512MB always remains after VMs are started.

https://technet.microsoft.com/en-us/library/ff817651(WS.10).aspx