Chapter 8. Citrix Load Management

8. Citrix Load Management

Terms you'll need to understand:

• Load evaluators

• Rules

• Default

• Advanced

• Boolean

• Moving Average

• Incremental

• Moving Average Compared to High Value

Concepts you'll need to master:

• How load management works

• What load evaluators are

• What rules are

Citrix's load management system, Load Manager, available as a component of MetaFrame Presentation Server, is one of the most sought-after features of MPS. It therefore is in a class of its own when compared to other server-based computing products. It's important for enterprise-class IT shops to be able to direct users to the least busy servers to maximize the users' experience when using a remote session to connect to applications. So what makes Citrix's load management so special and different? Citrix allows you to customize the criteria by which a load is spread across servers. Usually, the standard load balancer spreads user load across servers evenly, so if you have three servers in your farm, it ensures that user load is always equal on all servers.

Being able to spread the load is good, but what if you have processor-intensive applications, for example? If you spread user load evenly, users may become frustrated because a single user can hog the CPU on a server if the application he or she is running is CPU intensive . In this case, the other sessions that are connected to this server will be very slow, rendering them incapable of being productive.

With the Citrix load balancer, however, you can alleviate this problem by configuring your load based on a number of different resource criteria. You can, for example, configure it so it points users to a server that has very little CPU utilization. So using the preceding example, you may end up with a server that has 4 users on it and another server that has 10 users on it. The result is that all users are happy.