Solaris Tunable Parameters Reference Manual


Solaris Tunable Parameter Reference Manual provides reference information about Solaris kernel and network tunable parameters. This manual does not provide tunable parameter information about the CDE or Java environments.

It contains information for both SPARCTM based and IA based systems.

Note –

The SolarisTM operating environment is supported on two types of hardware, or platforms—SPARC and IA. The Solaris operating environment supports 64-bit and 32-bit address spaces. The information in this document pertains to both platforms and address spaces unless specified in a special chapter, section, note, bullet, figure, table, example, or code example.

Who Should Use This Book

This book is intended for experienced Solaris system administrators who might need to change kernel tunable parameters in certain situations. Refer to Tuning a Solaris System for guidelines on changing Solaris tunable parameters.

How This Book Is Organized

The following table describes the chapters in this book.

Chapter ... 

Provides ... 

Chapter 1, Overview of Solaris System Tuning

An overview of tuning a Solaris system and a description of the format used in the book to describe the kernel tunables 

Chapter 2, Solaris Kernel Tunables

A description of Solaris kernel tunables such as kernel memory, the file system, process size, and paging parameters 

Chapter 3, NFS Tunable Parameters

A description of NFS tunables such as caching symbolic links, dynamic retransmission, and RPC security parameters 

Chapter 4, TCP/IP Tunable Parameters

A description of TCP/IP tunables such as IP forwarding, source routing, and buffer sizing parameters 

Chapter 5, System Facility Parameters

A description of parameters for changing default values of certain system facilities by modifying files in the /etc/default directory

Appendix A, Tunable Parameter Change History

A history of parameters that have changed or are now obsolete 

Appendix B, Revision History for this Manual

A history of this manual's revisions that includes the current Solaris release version 

Related Books

The following books provide background material that might be useful when tuning Solaris systems.

Other Resources for Solaris Tuning Information

This table describes other resources for Solaris tuning information.

For ... 

Go To ... 

Performance tuning classes

Online performance tuning information

Ordering performance tuning documentation by Sun Microsystems Press

Ordering Sun Documents, an Internet professional bookstore, stocks select product documentation from Sun Microsystems, Inc.

For a list of documents and how to order them, visit the Sun Documentation Center on at

Accessing Sun Documentation Online

The docs.sun.comSM Web site enables you to access Sun technical documentation online. You can browse the archive or search for a specific book title or subject. The URL is

Typographic Conventions

The following table describes the typographic changes used in this book.

Table P–1 Typographic Conventions

Typeface or Symbol 




 The names of commands, files, and directories; on-screen computer output

Edit your .login file.

Use ls -a to list all files.

machine_name% you have mail.


 What you type, contrasted with on-screen computer output

machine_name% su



 Command-line placeholder: replace with a real name or value

To delete a file, type rm filename.


Book titles, new words, or terms, or words to be emphasized. 

Read Chapter 6 in User's Guide.

These are called class options.

You must be root to do this.

Shell Prompts in Command Examples

The following table shows the default system prompt and superuser prompt for the C shell, Bourne shell, and Korn shell.

Table P–2 Shell Prompts



 C shell promptmachine_name%
 C shell superuser promptmachine_name#
 Bourne shell and Korn shell prompt$
 Bourne shell and Korn shell superuser prompt#