Microsoft Sharepoint Products and Technologies Resource Kit eBook

212 Part III: Planning and Deployment
The following list provides key sizing metrics, along with typical values as a
guideline:
■ Number of users. The number of potential users with access to the portal
site.
■ Percent of active users per day. The percentage of the users who might
access the portal site during the day. This is typically between 10 percent and
50 percent. This is an important number and one that is usually a point of contention.
Most customers like to think that each user hits the corporate or divisional
portal site each day, but your experience might prove otherwise.
■ Operations per user per day. Accesses to the portal site Home page,
searches, category browses, document retrievals, media viewing, and so on.
Depending on the user’s role (whether it is reader, author, reviewer, or contributor),
this number will usually range between 1 and 10 operations per day.
■ Hours per day. Hours in the business day. Portal site access can cross time
zones, so 10 hours per day might be a typical number for a company spanning
the United States.
■ Peak factor. A ratio of how much the peak usage exceeds the average usage.
You should size the systems for peak usage so that performance does not
degrade during busy periods. A typical ratio is 5 to 1.
Note Peak factor is an approximate number that estimates the ratio of the
peak portal site throughput to its average throughput. This number typically
ranges from 1 to 5.
Next, using the following formula and the quantitative metrics of each portal
site’s usage characteristics, you will estimate the required portal peak throughput, in
operations per second.
Number of users × Percent of active users per day
× Number of operations per active user per day × Peak factor
360,000 × Number of hours per day
The constant 360,000 is derived from the following equation:
100 (percent conversion) × 60 (minutes per hour) × 60 (seconds per minute)
Break down the operations per active user per day by the type of site and
related functions, such as the following ones:
■ Corporate portal site access