Other tasks and characteristics of data domains

You can issue cache warming operations to the data domain's Dgraph processes, and configure session affinity for data domains. You can also learn how to connect to the data domains, how to load data, and how different types of data domains behave, such as read-only, idle, or oversubscribed data domains.

Endeca Server memory consumption
The Endeca Server query performance is dependent on many characteristics of your specific deployment, such as query workload, query complexity, data domain configuration, and the characteristics of the loaded records, as well as the size of the data domain's index. In view of these characteristics, a hardware sizing must be performed prior to deployment, to assess memory consumption and other hardware needs of your deployment.
About using control groups (cgroups) for data domains
On Oracle Enterprise Linux 6 (Red Hat Enterprise Linux Server release 6), Endeca Server has a new option to use cgroups to limit the total memory usage of Dgraph processes hosted on the machine. Control groups (also known as cgroups) is a kernel resource-controlling feature of the Linux 6 operating system. They provide a way to define and allocate the system resources to one or more specific processes, while controlling, at a high-level, the utilization of these resources, and ensuring that the processes do not consume excessive resources. In this way, cgroups help avoid situations where the hosting machines run out of memory for their functioning and are forced to shut down due to their hosted applications taking over all available resources on the machine.
Read-only data domains
When defining a data domain profile, you can specify whether the data domain should be created as read-only. Having a read-only data domain is useful in the development environment or for demonstration purposes — a read-only data domain does not allow changes to its index, but lets the application users issue read-type queries, such as regular search and navigation queries.
Auto-idling and oversubscribing behavior of data domains
Data domain profiles define two important aspects of data domain behavior — automatic idling and oversubscribing.
Issuing cache warming requests to the Dgraph
In a running data domain, you can issue a request to warm up the cache of its Dgraph processes.
Configuring session affinity for data domains
When receiving client requests, the Endeca Server cluster routes them to the arbitrary Endeca Server nodes hosting the appropriate data domains. Optionally, you can configure your data domain profile to utilize session affinity for request routing.
About connecting Web browsers to data domains
For security reasons, you should never allow user Web browsers to connect directly to the machine hosting the Endeca Server and the Endeca data domains.