Two resource kit tools give you an economical and effective alternative
If you've ever managed a large network with multiple Windows NT domains and hundreds of NT servers, you're familiar with the intensive labor hours you must spend gathering data for management reports and performance baselines. You typically spend a lot of time fighting fires as well. You might be looking at servers in the Eastern domain, while potential problems are building in the Western domain. You know third-party tools are available to simplify your job, but management can't see the added value and therefore won't approve the purchase. If you're suffering from this type of crisis-mode administration, consider a simple formula that can change the way you manage your servers: datalog.exe + monitor.exe = economical metrics and reporting.
Datalog.exe and monitor.exe are Microsoft Windows NT Server 4.0 Resource Kit tools that let you capture performance data from your servers without feeling the effect of running NT's Performance Monitor. With these two utilities, you won't need to leave a management server or workstation continually logged on and running Performance Monitor to gather metrics. Likewise, you won't need to drag performance data across your network every 30 minutes to a management server or workstation. Finally, you won't need to worry about losing performance data every time your management server or workstation shuts down or hangs.
Datalog.exe lets you run Performance Monitor as a service, and monitor.exe lets you easily control the Datalog service. Become familiar with these tools, and you'll soon be spending your time designing and optimizing instead of troubleshooting and explaining.
Using the Datalog Service
When you use datalog.exe to run Performance Monitor as a service, you can capture performance data at regular intervals without degrading the target server's performance. Microsoft maintains that gathering data in this fashion adds less than 0.5 percent overhead on the server. This reduced overhead is possible because the Performance Monitor GUI is not running. Instead, the Datalog service collects data from the target server at user-specified intervals and writes the data to a local .log file. As a result of this process, the Datalog service doesn't affect network performance because it doesn't need to send the collected data across the network. Whenever possible, configure the Datalog service when you build the server (i.e., before you bring the server into production) so that you'll have performance data available for tweaking and tuning the server.
Unlike Performance Monitor, the Datalog service doesn't require that you log on as a user to gather data. The service is invaluable for troubleshooting network performance problems and for gathering baseline measurements. However, the data you gather and the frequency of collection can vary widely depending on the type of reporting you are performing.
Setting Baselines and Gathering Reporting Data
When you capture data for baseline and reporting purposes, set the collection interval to every 30 minutes or every hour, depending on the maturity and stability of your servers. Baseline data helps you set performance standards so you can evaluate your servers and network performance. After you determine the average performance baseline for an object or instance, you can use that information as a reference point to determine when tuning or upgrades are necessary. Systems administrators who don't set baselines and then make recommendations to customers or management miss a valuable opportunity to demonstrate effective resource management. By regularly tracking and analyzing performance data against the baselines, you can respond quickly and appropriately to changes in your network. You also have reliable data at your fingertips the next time you broach the subject of additional upgrades or servers.
Another important function, and the one most visible to customers and management, is reporting. Service-level agreements and contracts specify that the service provider report information to the customer on a weekly, monthly, quarterly, or annual basis. Both customers and management want to know whether they are taking full advantage of the existing hardware, how well they're managing their hard disk space, and how much bang they're getting for their hardware expenditures. You can add value to your service by proactively informing your customers or management whether they're using the existing hardware to its full extent. Furthermore, you can use the historical data you collect to predict trends for future growth.
Knowing Which Objects to Log
Determining which objects to track depends on the function of each server. For example, a server running SQL Server has many objects, as you see in Screen 1, that don't appear on a file-and-print server or on a Primary Domain Controller (PDC). Be sure to log the following objects on all servers: memory, processor, system, physical disk, paging file, logical disk, network interface, and objects specific to the function of the server.
Use the collected data from the previous objects to establish baselines, troubleshoot your systems, and prepare customer reports. Periodically compare the data you collect with the baseline standards you see in Table 1. These standards are suggested starting points for interpreting performance data. These counters don't mean a lot when you view them individually. To gain any meaning and insight into your server's performance, you must look at the counters as a whole in relation to the performance baselines you obtain.