Solaris System Limit Setup

The UNIX/Linux operating system maintains a configurable list of system resource limits. The ones relevant to this discussion are listed in the following table.

Table 3 System Resource Parameters 

Parameter	Description
pt_cnt	Number of ptys allowed on the system
rlim_fd_cur	Maximum number of open file descriptors allowed per process
semmnu	Maximum number of semaphore undo structures allowed system-wide
shmmax	Maximum size of a shared memory segment
shmmin	Minimum size of a shared memory segment
shmmni	Maximum number of shared memory segments system-wide
shmseg	Maximum number of shared memory segments to which a single process can attach

An application cannot consume more system resources than allowed for by the system limits. In most cases, when an application tries to consume more system resources than allowed, no system messages are generated to notify the user of the resource allocation failure.

In particular, there may be cases where Rose fails to execute correctly due to an attempt to use more system resources than allowed. For example, consider the application that opens many files. After the application has already opened the maximum number of files allowed, its attempt to open one more file will not succeed. The application may crash or may stop functioning properly.

The solution to the problem is to modify the system resource limits to suit the applications needs.

The rest of this section discusses some of the system resource limits that an application may exceed, and describes how to modify the appropriate system settings to enable the application to execute correctly.

Note: The following procedures are intended for system administrators; root password privilege is required to change UNIX/Linux system parameters.

Note: On Solaris, the system limits are set by modifying the file /etc/system. Changes in this file only take effect after the system is rebooted. Since the changes to /etc/system may cause a failure to reboot, back up the file before using it. It is possible to reboot the system from the boot prompt with the command b -as to choose which system configuration files to use during boot. For more information regarding the Solaris /etc/system file format, see the man pages at:

$ man -s 4 system