Often times I’m called in to perform a health check of a VMware Horizon environment due to a performance or operational issue. These issues make the environment unstable and effect user productivity. There are various things we can do in the environment to optimize the persistent or non-persistent virtual desktops, but first we need to make sure the virtual desktop infrastructure is configured properly.
Proper configuration entails proper server sizing. More often than not, these servers are not sized properly. Under-sizing causes performance issues and over-sizing wastes resources.
Running in a redundant environment using the Security Server model, we will need 28vCPU and 68GB of RAM (2 Internal Connection Servers, 2 External Connection Servers which are paired to Security Servers, 2 Security Servers and 1 Composer Server).
In a non-redundant environment using the Security Server model we will need 16vCPU and 40GB of RAM (1 Internal Connection Server, 1 External Connection Server which are paired to the Security Server, 1 Security Server and 1 Composer Server).
If we run the same redundant configuration using the Horizon Access Point model we will need 16vCPU and 32GB of RAM (2 Connection Servers, 2 Access Point Appliances and 1 Composer Server). In a non-redundant environment using the Access Point model we will need 10vCPU and 22GB of RAM 1 Connection Server, 1 Access Point Appliance and 1 Composer Server).
These servers run a java virtual machine process that scales itself to the amount of RAM that the server has. This java virtual machine process is the main process to make the environment function.
The good news is that if your Horizon environment is running version 6.x+ the java virtual machine process can dynamically adjust. So if the Connection/Security Server is powered off, resources adjusted and powered back on, everything should be fine.
Unfortunately, if your environment is not at or above this version, adjusting the resources on the Connection/Security Server does not make the java virtual machine process adjust.
You can read more about the differences and if you should deploy the Security Server model or the Access Point model here.
I hope that clears up your proper sizing questions so you dont run into configuration issues. If you do though,
Lewan Technology is a VMware Premier Solutions Partner headquartered in Denver, Colorado, with certified technical professionals in server virtualization, business continuity, desktop virtualization, hybrid cloud, management operations and software-defined storage.