Query: sys_attrs
OS: osf1
Section: 5
Format: Original Unix Latex Style Formatted with HTML and a Horizontal Scroll Bar
sys_attrs(5) File Formats Manual sys_attrs(5)NAMEsys_attrs - introduction to kernel subsystem attributes used for configuration and tuningDESCRIPTIONThe operating system kernel is built from many mandatory and optional subsystems. If you are logged into the root account, the following command lists the subsystems included in the kernel for your system: # /sbin/sysconfig -s The majority of the kernel subsystems have sets of attributes whose values control different aspects of subsystem configuration. You can examine the names, the current settings, and (if applicable) the minimum, and maximum settings of attributes for a particular subsystem by using the /sbin/sysconfig command. The -q option followed by the subsystem name displays attribute names and current settings. The -Q option followed by the subsystem name displays minimum and maximum settings and the kinds of operations permitted on the attribute (Config- urable (at boot time), Reconfigurable (at run time), Query only). In the Common Desktop Environment (CDE), you can run the dxkerneltuner application to get the same information. Caution A relatively small number of the attributes listed in displays from these interfaces should actually be changed through these same inter- faces and then only as part of the system configuration and tuning tasks done by an experienced system or network administrator. The set- ting of most subsystem attributes should be done indirectly through system and network setup applications or be automatically adjusted by the kernel. This fact is very important to remember because attribute settings can have complex interrelationships with one another, requiring (in some cases) careful manipulation of an entire set of attributes rather than only one. Furthermore, default settings of some subsystem attributes should never be touched, except by support personnel or by an administrator acting on instructions from support per- sonnel or patch kit documentation. Some attributes are modifiable at run time for ease of system tuning. Others are modifiable at run time only because of a software requirement and should not be changed manually. In general, do not change the default value of any system attribute manually unless the system documentation or your support representative provides directions for changing it. Some attributes have corresponding parameters in the system configuration file. If so, the corresponding parameter name in the system con- figuration file is specified in parentheses following the attribute name. In these cases, never edit the system configuration file to directly change the value of the system parameter; use the dxkerneltuner application or the /sbin/sysconfig -r command to change the value of the attribute. For some subsystems, these values are best applied through a stanza-formatted file that is specified as a parameter to the sysconfigdb command. See dxkerneltuner(8), sysconfig(8), and sysconfigdb(8) for more information about your options for configuring kernel subsystems. The following subsystems must be included when the kernel is built: Configuration Manager (cm) Generic Kernel (generic) Interprocess Commu- nication (ipc) Process (proc) Virtual File System (vfs) Virtual Memory (vm) A kernel also includes a processor-specific subsystem whose name is an internal code for a particular processor. Processor-specific subsys- tems typically have no attributes, are not modified directly by users, and are not documented. Other kernel subsystems are technically optional, although a kernel almost always includes quite a few optional subsystems in order for a system to be useful. For information on the attributes for a particular subsystem, refer to the reference page for that subsystem. The names of these reference pages adhere to the format sys_attrs_subsystem-name. For example, to see the reference page that lists and describes attributes for the generic subsystem, you can type man sys_attrs_generic at the system command line. For guidelines on changing kernel subsystem attributes to improve system performance, see the System Configuration and Tuning manual. Any discussion about changing attributes for reasons other than tuning is located in the appropriate administration or program debugging man- ual. You can adjust some subsystem attribute values at run time. If so, the attribute descriptions mention that fact. To make it easy for you to locate these attributes when scanning lists, an asterisk (*) also precedes the names of these attributes.SEE ALSOCommands: dxkerneltuner(8), sysconfig(8), sysconfigdb(8) Others: sys_attrs_cm(5), sys_attrs_generic(5), sys_attrs_ipc(5), sys_attrs_proc(5), sys_attrs_vfs(5), sys_attrs_vm(5) This list includes only reference pages for technically required subsystems. The number of subsystems that can be configured in a kernel is very large, so all system attribute reference pages are not listed here. System Configuration and Tuning System Administration Network Administration Kernel Debugging sys_attrs(5)
Related Man Pages |
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sysconfig(8) - osf1 |
sys_attrs(5) - osf1 |
sys_attrs_cam(5) - osf1 |
sys_attrs_pwrmgr(5) - osf1 |
cfg_reconfigure(9r) - osf1 |
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