Windows 2012 RDP - FairShare

After we saw that slow performance was not related to Harbour, we start doing a step by step installation of Windows Server 2012 R2, checking performance after each step.

Just after installing “RDS - Remote Desktop Services”, in Windows Server 2012 R2, I/O performance drops down (up to 8 times slower then before installing “RDS”), with only one user connected to VM…

After some research, we saw that, in “Windows 2012”, a feature named “Dynamic Fair Share Scheduling (DFSS) / CPU Fairshare” was enabled by default, and tries to share CPU/Net resource in equal base to all processes.

As we didn't find, in Windows 2012, any specific group policy, we disabled this directly via registry setting.

Without reboot, I/O performance changed to normal, just a second later !

Disk (1 - enable, 0 - disable) HKLM\SYSTEM\CurrentControlSet\Services\TSFairShare\Disk\EnableFairShare

NetFS (1 - enable, 0 - disable) HKLM\SYSTEM\CurrentControlSet\Services\TSFairShare\NetFS\EnableFairShare

IMPORTANT NOTES: - Read carefully TechNet texts about this, before doing any change ! - This chance can help only if your server has RDS, and I/O performance is much more slower than a normal performance. - We didn't know if this change can cause any side-effects. - In other Windows versions (ex: 2008), registry keys are different.

We will post any additional information, if we find any side-effect.