Monitoring User Processes

Monitoring User Processes

Not all processes require the same amount of system resources. Some processes, such as database applications working with large files, tend to be disk intensive, requiring a great deal of reading from and writing to the disk as well as a large amount of space on the disk. These activities take up CPU time. Time is also spent waiting for the hardware to perform the requested operations. Other jobs, such as compiling programs or processing large amounts of data, are CPU intensive, since they require a great number of CPU instructions to be performed. Some jobs are memory intensive, such as a process that reads a great deal of data and manipulates it in memory. Since the disk, CPU, and memory resources are limited, if you have more than a few intensive processes running at once on your system, you may see a performance degradation.

As the administrator, you should be on the lookout for general trends in system usage, so you can respond to them and keep the systems running as efficiently as possible. If a system shows signs of being overloaded, and yet the total number of processes is low, your system may still be at or above reasonable capacity. The following sections show four ways to monitor your system processes.

Monitoring Processes With top
Monitoring Processes With osview
Monitoring Processes With sar
Monitoring Processes With ps
Prioritizing Processes With nice
Terminating Processes