Estimating the Number of Clients and Objects

The hardware requirements of your SMS site systems depend on the number of objects your site servers needs to process. Objects are items that are processed and stored in your SMS site database. SMS uses objects to move and store client and server data. Each SMS feature creates different types of objects. The most common objects are the following:

• Discovery data records (DDRs), which are produced by discovery methods
• Management Information Format (MIF) files, which are produced by hardware inventory
• Software inventory files (SICs and SIDs)
• Status VarFiles (SVFs)

You can configure many SMS components to control the number of objects they produce. Table 2.2 lists the objects generated by SMS features.

After the initial hardware and software inventory is taken on clients, SMS uses delta objects, objects that contain only changes to configuration — not the entire configuration — and are smaller and process faster than standard objects. When you perform sizing tests, however, be sure to consider that SMS will occasionally request a resynchronization operation. When this happens, all of the clients in the site will report full objects during their next cycle. Your site can become overwhelmed in this peak situation if you are using network connections that can only maintain the flow of the smaller delta objects.

Tables 2.3 through 2.7 list the number of objects generated by each feature and a suggested starting point for the sizing of your site server hardware based on the number of clients you plan to install in your SMS site hierarchy.

The numbers in these tables are based on SQL Server version 7.0 installed on the same computer as SMS, a five-day work week, new advertised programs every week, a separate site system assigned the role of software metering database server, and all site systems running Windows NT Server 4.0, Service Pack 4.

If you plan to install SQL Server on a computer that is not the site server, you need to consider any network bottlenecks that might occur between the two computers. Even with a fast network connection between the two computers, running SQL Server on a remote computer will be inherently slower than running SQL Server on the site server. As a result, the computers that you buy for both SMS and SQL Server should have more combined power than that of a single site server computer that also runs SQL Server. For more information about the relationship between SMS and SQL Server and the associated hardware requirements, see “SMS and SQL Server” later in this chapter.

The following data is also based on the assumption that the SMS Administrator console will be run remotely most of the time, rather than run directly on the site server. If you plan to use the SMS Administrator console heavily on the site servers, you should consider a faster CPU and more RAM for the site servers to improve the performance of the console.

The recommended hardware listed in this table meets the requirements of zero processing backlog and responsive help desk operations from remote consoles, as well as additional processing capacity to ensure timely recovery while attempting to keep the price of the hardware at a minimum.

It is difficult to make exact hardware recommendations for SMS sites that will have fewer than 500 clients; while there is typically a light load placed on the SMS system by the clients, other factors, such as the amount of local SMS Administrator console activity, might make significant demands on the SMS system.

Table 2.3 Recommended Site Server Hardware Sizes for Organizations with up to500 Clients

Table 2.4 Recommended Site Server Hardware Sizes for Organizations with up to5,000 Clients

Table 2.5 Recommended Site Server Hardware Sizes for Organizations with up to20,000 Clients

Table 2.6 Recommended Site Server Hardware Sizes for Organizations with up to50,000 Clients

Table 2.7 Recommended Site Server Hardware Sizes for Organizations with up to100,000 Clients

For small test sites, you will probably use the SMS Administrator console locally and perform actions quickly, and you will want short response times. In such a situation, you will need a more powerful computer, such as a Pentium II 266 MHz and at least 128 MB of RAM.

However, for small remote secondary sites that will service your organization by acting only as a small point of presence for a handful of clients, you might only need very basically-equipped, low-end computers, such as those with Pentium 100 MHz CPUs and 64 MB of RAM. By using low-end computers in these cases, you can save a substantial amount of money compared to buying newer, faster computers.

For SMS sites that will have more than 100,000 clients, you can build them by using dual-processor and quad-processor high-end computers with high-performance disk subsystems and plenty of memory; however, because the performance variables become very unpredictable at this size, it is especially critical that you run a pilot project to properly estimate your site server hardware.