Estimating Load Distribution on Cognos Server
In Cognos 8, load is generated by two main factors. They are 1.) User navigation and processing requests, such as requests to run or view reports, and 2.) Requests made through automated or event-driven processes, including scheduled and burst reports. By determining when users are most likely to be using Cognos 8 and submitting processing requests, you can then decide when to schedule automated processes. This allows you to distribute the processing load evenly over time, so that you make the best use of your system resources to maintain optimal performance.
The key to doing this is estimating the number of concurrent users that will be applying load to your Cognos 8 system at any time. Some of the main factors to consider are business hours, business practices, and the geographic distribution of users. These factors can determine how the concurrency rate changes over time, and how you choose to ensure adequate capacity.
A Business Intelligence application in which requests are spread evenly throughout the day has a lower peak concurrency ratio than an application in which the majority of requests are limited to a specific time of day. For example, if users are concentrated in one time zone, there will likely be heavy demand during business hours, followed by a period of low demand after hours. In this situation, you may be able to manage peak and non-peak time periods by sharing hardware resources between interactive and non-interactive processes. You would schedule automated activity to run in non-peak times to produce content for retrieval by interactive users in peak times.
On the other hand, if your user population is distributed across several time zones, user load on the system tends to be spread out over more hours, and there are fewer available non-peak hours for scheduled activities. In this situation, you may choose to dedicate separate hardware resources for interactive and non-interactive use.
Source: Cognos Architecture and Planning Guide 8.1
