Hosted Shared Desktops and  application virtualization will be hosted on RDS servers so it is important to know that maximum load can be carried on a single RDS server.  Generally  this can be anywhere between 5 and 50, depending on the following factors:
  • Speed, type and number or CPUs installed on the Accops Hyworks Session Host (RDS)server.
  • Amount of RAM installed in the Session Host  (remote desktop) server.
  • Server's Host Operating System, i.e. Windows 2003, 2008, 2008 R2 ,2012 or 2016  server.
  • Client settings, i.e. local resource redirection, screen resolution & color depth.
  • Other services running on the server, i.e. Active Directory, Exchange, SQL... (NOT recommended).
  • Bandwidth available for Remote Desktop sessions (a main consideration for WAN connections).
  • End-user applications being used in each session, i.e. Microsoft Office, Acrobat Reader, Internet Explorer etc

Application virtualization sessions  and shared Hosted desktop sessions load should be calculated separately as Hosted shared desktops runs with explorer.exe and additional processes will be running on it which will increase requirement of resources. Server load and number of sessions can be calculated based on the actual user application requirements. A trail run should be conducted and calculated the average  usage of the RAM and CPU per user 

Here are general recommendations and suggestions for sizing and scaling Remote Desktop Servers.

NOTE: This is just a reference guide. Accops do not guarantee server sizing as the actual sizing of servers depends on the applications and resources made available to users within their Accops sessions

General guidelines:

  • 2 Dual Core CPU perform better then single Quad core processor.
  •   light weigh application  on a RDS session host  will be used an average of 100 MB RAM  per user . Additional 4GB RAM should be considered for Operating System.  For example, (100 users *  64 ) + 4000 = 10.4 GB i.e. 12GB RAM. Each application will then add more memory per user which will need to be added to the calculation.
  • Recommended number of concurrent sessions per server is between 30-40
  • Storage read-write operations are  one of the important parameters for deciding no. of concurrent sessions.  Application virtaulization and shared VDI requires continious read and write operations so consider iOPs calculation. Average usage of applications & Shared desktops uses 6IOPS /user
  • 10 RDS sessions per CPU core is the optimum performance limit.
  • 128kbps is the ideal bandwidth per RDS session. Bandwidth will vary based on the 
  • RDS performance is significantly enhanced when running x64 hardware and OS. Please refer Performance optimization guide for more information for better RDS performance
  • Remember that enabling Desktop Composition will have a significant impact on resource usage and will affect server capacity negatively.
  • When running RD Session Host servers in a virtualized environment, make sure the processor supports paging at the hardware level (RVI for AMD, EPT for Intel).