SOS System Configuration Summary

The System Configuration Screen

The System Configuration screen displays various configurable kernel parameters. Figure 22.1 shows an example of the screen.

Figure 22.1 SOS System Configuration screen

To access the System Configuration screen from any SOS display screen:

Type s from the SOS Enter command: prompt to view the Screen Selection Menu screen.

From the Screen Selection Menu screen, enter y (System Configuration). The System Configuration screen will display.

System Configuration Screen Display Items

SYSTEM CONFIGURATION

The SYSTEM CONFIGURATION portion of the System Configuration screen displays system configuration parameters.

Table 22.1 SOS SYSTEM CONFIGURAITON data items

Data Item	Description
system name	The specific name of the system assigned during the system installation.
serial num	The serial number of the system.
os version	The version of the operating system.
boot time	The time of the last system reboot.
cpu type	The type of CPU hardware and model.
run level	The Unix state of operation. For information about run levels, please refer to the "inittab" Unix man page.

MEMORY MANAGEMENT CONFIG

The MEMORY MANAGEMENT CONFIG portion of the System Configuration screen displays memory management parameters.

Table 22.2 SOS MEMORY MANAGEMENT data items

Data Item	Description
lotsfree	The upper bound for paging. Once paging has started, it will continue until the amount of free memory is larger than the set lotsfree parameter.
desfree	The lower bound for paging. When the amount of free memory drops below the set desfree parameter, paging begins.
minfree	The threshold value at which the system considers itself to be out of memory. At this point, the system will start to deactivate processes.
throttlefree	The value at which the amount of free memory pages reaches throttlefree pages. At this point, any process that attempts to get another page will be suspended until the amount of free memory exceeds desfree.
priority paging	The priority paging value indicates whether or not priority paging is enabled. 0 indicates priority paging is disabled. 1 indicates priority paging is enabled. When priority paging is enabled, the paging algorithm is modified to page out data pages before text, heap, and stack.
maxpgio	The maximum number of page I/O operations per second that the system will schedule.
page size	The size (bytes) of the pages.
fastscan	The fastest scan rate (pages per second). The fastscan value corresponds to an empty free list.
slowscan	The initial scan rate (pages per second). This rate occurs when page scanning starts.

FSFLUSH CONFIGURATION

The FSFLUSH CONFIGURATION portion of the System Configuration screen displays information about the file system flush configuration.

Table 22.3 SOS FSFLUSH CONFIGURATION data items

Data Item	Description
ufs_LW	The minimum threshold value (kilobytes) for unflushed data. If the amount of data pending to be flushed to a file is less than the ufs_LW value (kilobytes), the data will be flushed by fsflush. If the amount of data pending to be flushed to a file is between the ufs_LW value and the ufs_HW value (the maximum threshold), writes to disk are scheduled, bypassing fsflush. If the amount of data pending to be flushed is greater than the ufs_LW value, any additional writes will result in suspension of the process until the amount pending drops below the ufs_LW value.
ufs_HW	Refer to the description of ufs_LW.
autoup	The maximum number of seconds that a modified page will remain in memory without being written to disk by fsflush.
t_fsflushr	The set interval (number of seconds) between instances when fsflush scans 1/6 of RAM.
doiflush	The doiflush parameter indicates whether or not fsflush is enabled to flush the inode cache. 0 indicates inode cache flushing is disabled. 1 indicates inode cache flushing is enabled.
dopageflush	The dopageflush parameter indicates whether or not fsflush is enabled. 0 indicates page flushing is disabled. 1 indicates page flushing is enabled.

CACHE/BUF CONFIGURATION

The CACHE/BUF CONFIGURATION portion of the System Configuration screen displays information about the SYSV buffer cache parameters.

Table 22.4 SOS CACHE/BUF CONFIGURATION data items

Data Item	Description
ufs_ninode	The maximum possible number of entries in the inode cache. The size of the inode cache is dynamic.
ncsize	The configured number of entries for the DNLC cache.
nbuf	The configured number of buffer cache headers on the system. This number will change over time if the DBC (dynamic buffer cache) is configured.
bufhwm	The maximum threshold value for the number of buffers configured in the SYSV buffer cache.
ncallout	The number of callout structures configured.

PROCESS CONFIGURATION

The PROCESS CONFIGURATION portion of the System Configuration screen displays information about the process configuration parameters.

Table 22.5 SOS PROCESS CONFIGURATION data items

Data Item	Description
rlim_fd_cur	The soft limit maximum of open files allowed by a process.
rlim_fd_max	The hard limit maximum of open files allowed by a process. Only processes with root privileges can exceed rlim_fd_cur and use rlim_fd_max.
maxuprc	The maximum number of processes any one user can own.
max_nproc	The maximum possible number of entries for the process table. The size of the process table is dynamic.

IPC CONFIGURATION

The IPC CONFIGURATION portion of the System Configuration screen displays information about the SYSV IPC (interprocess communication) configuration parameters.

Table 22.6 SOS IPC CONFIGURATION data items

Data Item	Statistics	Description
MESSAGES	msgmax	The maximum size (bytes) of a single message.
	msgmnb	The maximum number of bytes on the message queue (at one time).
	msgssz	The size (bytes) of each message segment. The message buffer cache size is calculated: Message Buffer Cache Size (bytes) = msgseg * msgssz
	msgseg	The number of segments allocated in the message buffer cache.
	msgmap	The configured number of message map entries.
	msgmni	The configured number of message queue identifiers.
	msgtql	The configured number of message headers. A message header is used for each message queued in the system.
SEMAPHORES	semmap	The configured number of SYSV semaphore map entries.
	semmni	The configured number of SYSV semaphore identifiers. A semaphore identifier may refer to multiple semaphores.
	semmns	The configured number of SYSV semaphores available.
	semvmx	The maximum value that a SYSV semaphore is allowed to reach.
	semaem	The maximum value at which at a SYSV semaphore can be undone.
	semmnu	The configured number of "undo’s" on a system.
	semume	The maximum number of "undo’s" entries per process.
SHARED MEM	shmmax	The maximum shared memory segment size (bytes).
	shmmni	The configured number of shared memory identifiers.
	shmseg	The maximum number of shared memory segments that can be attached to a process.