Solaris Containers: Resource Management and Solaris Zones Developer's Guide

Overview of Projects and Tasks

The Solaris Operating System uses the workload hierarchy to organize the work being performed on the system. A task is a collection of processes that represents a workload component. A project is a collection of tasks that represents an entire workload. At any given time, a process can be a component of only one task and one project. The relationships in the workload hierarchy are illustrated in the following figure.

Figure 2–1 Workload Hierarchy

Diagram shows the relationships among projects, tasks,
and processes.

A user who is a member of more than one project can run processes in multiple projects at the same time. All processes that are started by a process inherit the project of the parent process. When you switch to a new project in a startup script, all child processes run in the new project.

An executing user process has an associated user identity (uid), group identity (gid), and project identity (projid). Process attributes and abilities are inherited from the user, group, and project identities to form the execution context for a task.

For an in-depth discussion of projects and tasks, see Chapter 2, Projects and Tasks (Overview), in System Administration Guide: Solaris Containers-Resource Management and Solaris Zones. For the administration commands for managing projects and tasks, see Chapter 3, Administering Projects and Tasks, in System Administration Guide: Solaris Containers-Resource Management and Solaris Zones.

/etc/project File

The project file is the heart of workload hierarchy. The project database is maintained on a system through the /etc/project file or over the network through a naming service, such as NIS or LDAP.

The /etc/project file contains five standard projects.


This project is used for all system processes and daemons.


All root processes run in the user.root project.


This special project is for IPQoS.


A default project is assigned to every user.


This project is used for all users in the group staff.

To access the project file programmatically, use the following structure:

struct project {
  char      *pj_name;       /* name of the project */
  projid_t   pj_projid;     /* numerical project ID */
  char      *pj_comment;    /* project comment */
  char     **pj_users;      /* vector of pointers to project user names */
  char     **pj_groups;     /* vector of pointers to project group names */
  char      *pj_attr;       /* project attributes */

The project structure members include the following:


Name of the project.


Project ID.


User-supplied project description.


Pointers to project user members.


Pointers to project group members.


Project attributes. Use these attributes to set values for resource controls and project pools.

Through project attributes, the resource usage can be controlled. Four prefixes are used to group the types of resource control attributes:

For the complete list of resource controls, see resource_controls(5).