Remote Desktop Services Hardware Sizing and Capacity Planning Guidance.

We always felt the need of Hardware capacity guidance and sizing information for Remote Desktop services, Whenever I am involved in architectural guidance discussion for RDS deployment, a question is raised that what Hardware configuration should be consideration.

Below are the points which I do recommend to my partners and customers:

  • 2GB Memory (RAM) is the optimum limit for each core of a CPU. E.g. If you have 4 GB RAM then for optimum performance there should be Dual core CPU.
  • 2 Dual Core CPU perform better than single Quad core processor.
  • 15 Remote session per CPU core is the optimum performance limit of a Remote Desktop Server.

3.0 GHz x 4 cores x 1.25 (hyper-threading) = 15.0 GHz

There are 2 set of users as mention below.

1st user case who required 600 MHz – 800 MHz per user processing power.

3.0 GHz x 4 cores x 1.25 (hyper-threading) = 15.0 GHz = 18 to 25 users

2nd user cases, 1.0 GHz – 1.2 GHz per user processing power is sufficient provisioning

3.0 GHz x 4 cores x 1.25 (hyper-threading) = 15.0 GHz = 12 to 15 users

  • On a Remote Desktop Server 64 MB per user is the based Memory (RAM) requirement for GPO use + 2 GB for OS E.g. (100 users * 64) + 2000 = 8.4 GB i.e. 8GB RAM.
  • More applications used (i.e. Office, ERP / PDF Reader / File Archive and Compressor / Web Based App / Browser / Video CAD Apps and etc.) will require more memory per user to be added to this calculation over the 64 MB base memory per user.

Considered RAM / Memory for below Work Force

  • Task / Basic Worker:- MS Office / PDF Ready

(200 + 64) * 100 users + 2000 = 28.4 GB. Go for 28 GB RAM

  • Knowledge Worker: – MS Office with PPT / PDF Ready / ERP / File Archive and Compressor / Browser / Web Based App.

(460*1000 + 64) * 100 users + 2000 = 54.4 GB. Go for 54 GB RAM

  • Power User:- Same as Knowledge Worker along with Graphic Design

(600*100 + 64) * 100 users + 2000 = 68.4 GB. Go for 68 GB RAM

  • CPU performance degrades if %processor time per core is constantly above 65%.
  • Network should not have more than 5 hops, and latency should be under 100ms.
  • 64 kbps is the Bandwidth per user session. (256 color, switched network, bitmap caching only). But in real time / ideal it should be around 80 kbps
  • Remote Desktop Server performance doubles when it is running on an X64 HW and OS.

The Remote Desktop Session Host (RD Session Host) role service lets multiple concurrent users run Windows®-based applications on a remote computer running Windows Server® 2008 R2. This intended as a guide for capacity planning of RD Session Host in Windows Server 2008 R2. It describes the most relevant factors that influence the capacity of a given deployment, methodologies to evaluate capacity for specific deployments, and a set of experimental results for different combinations of usage scenarios and hardware configurations.

You can also use this document for sizing Remote Desktop Services on a Hyper V Platform.

Will be soon posting a guide on Sizing Server Hardware for Desktop Virtualization (VDI) and will be considered Four major criteria for sizing up host servers

There are four major criteria to consider when sizing up virtual server hardware:
a) CPU / Processor
b) RAM / Memory
c) Storage / Hard Disk resources
d) Network

Keep looking for it in near future.