As an operating system, Oracle Solaris adjusts easily to system load and thus requires minimal tuning. However, in certain cases, tuning might be necessary. This book provides details about the officially supported tuning options available for Oracle Solaris.
The Oracle Solaris kernel is composed of a core portion, which is always loaded, and a number of loadable modules that are loaded as these modules are being referenced. Many kernel parameters listed in this guide are core parameters. However, a few parameters belong to loadable modules.
Note that to improve performance, tuning system parameters most often is the least effective method to use. Improving and tuning the application is a better and more effective approach. Moreover, adding more physical memory and balancing disk I/O patterns can also increase performance. Only in a few rare cases does changing system parameters provide substantial benefits to performance.
Remember that one system's /etc/system settings might not be applicable, either wholly or in part, to another system's environment. Carefully consider the values in the file with respect to the environment in which they will be applied. Make sure that you understand the behavior of a system before attempting to apply changes to the system variables listed this book.
To tune an Oracle Solaris system, create an empty file. Provide the file with a company specific name and separate the components of the file name with a colon, for example, MyCompany:kernel:configurations. As a first step, add only those tunables that are required by in-house or third-party applications. After baseline testing has been established, evaluate system performance to determine if additional tunable settings are required.
Caution - The tunable parameters described in this book can and do change from one Oracle Solaris release to the next. Publication of these tunable parameters does not preclude changes to the tunable parameters and their descriptions without notice.