Chapter 2 Projects and Tasks (Overview)

This chapter discusses the project and task facilities of Solaris resource management. Projects and tasks are used to label workloads and separate them from one another.

The following topics are covered in this chapter:

• Project and Task Facilities

• Project Identifiers

• Task Identifiers

• Commands Used With Projects and Tasks

To use the projects and tasks facilities, see Chapter 3, Administering Projects and Tasks.

Project and Task Facilities

To optimize workload response, you must first be able to identify the workloads that are running on the system you are analyzing. This information can be difficult to obtain by using either a purely process-oriented or a user-oriented method alone. In the Solaris system, you have two additional facilities that can be used to separate and identify workloads: the project and the task. The project provides a network-wide administrative identifier for related work. The task collects a group of processes into a manageable entity that represents a workload component.

The controls specified in the project name service database are set on the process, task, and project. Since process and task controls are inherited across fork and settaskid system calls, all processes and tasks that are created within the project inherit these controls. For information on these system calls, see the fork(2) and settaskid(2) man pages.

Based on their project or task membership, running processes can be manipulated with standard Solaris commands. The extended accounting facility can report on both process usage and task usage, and tag each record with the governing project identifier. This process enables offline workload analysis to be correlated with online monitoring. The project identifier can be shared across multiple machines through the project name service database. Thus, the resource consumption of related workloads that run on (or span) multiple machines can ultimately be analyzed across all of the machines.

Project Identifiers

The project identifier is an administrative identifier that is used to identify related work. The project identifier can be thought of as a workload tag equivalent to the user and group identifiers. A user or group can belong to one or more projects. These projects can be used to represent the workloads in which the user (or group of users) is allowed to participate. This membership can then be the basis of chargeback that is based on, for example, usage or initial resource allocations. Although a user must be assigned to a default project, the processes that the user launches can be associated with any of the projects of which that user is a member.

Determining a User's Default Project

To log in to the system, a user must be assigned a default project. A user is automatically a member of that default project, even if the user is not in the user or group list specified in that project.

Because each process on the system possesses project membership, an algorithm to assign a default project to the login or other initial process is necessary. The algorithm is documented in the man page getprojent(3C). The system follows ordered steps to determine the default project. If no default project is found, the user's login, or request to start a process, is denied.

The system sequentially follows these steps to determine a user's default project:

1. If the user has an entry with a project attribute defined in the /etc/user_attr extended user attributes database, then the value of the project attribute is the default project. See the user_attr(4) man page.

2. If a project with the name user.user-id is present in the project database, then that project is the default project. See the project(4) man page for more information.

3. If a project with the name group.group-name is present in the project database, where group-name is the name of the default group for the user, as specified in the passwd file, then that project is the default project. For information on the passwd file, see the passwd(4) man page.

4. If the special project default is present in the project database, then that project is the default project.

This logic is provided by the getdefaultproj() library function. See the getprojent(3PROJECT) man page for more information.

Setting User Attributes With the useradd, usermod, and passmgmt Commands

You can use the following commands with the -K option and a key=value pair to set user attributes in local files :

passmgmt

Modify user information

useradd

Set default project for user

usermod

Modify user information

Local files can include the following:

• /etc/group

• /etc/passwd

• /etc/project

• /etc/shadow

• /etc/user_attr

If a network naming service such as NIS is being used to supplement the local file with additional entries, these commands cannot change information supplied by the network name service. However, the commands do verify the following against the external naming service database:

• Uniqueness of the user name (or role)

• Uniqueness of the user ID

• Existence of any group names specified

For more information, see the passmgmt(1M), useradd(1M), usermod(1M), and user_attr(4) man pages.

project Database

You can store project data in a local file, in the Domain Name System (DNS), in a Network Information Service (NIS) project map, or in a Lightweight Directory Access Protocol (LDAP) directory service. The /etc/project file or naming service is used at login and by all requests for account management by the pluggable authentication module (PAM) to bind a user to a default project.

Updates to entries in the project database, whether to the /etc/project file or to a representation of the database in a network naming service, are not applied to currently active projects. The updates are applied to new tasks that join the project when either the login or the newtask command is used. For more information, see the login(1) and newtask(1) man pages.

PAM Subsystem

Operations that change or set identity include logging in to the system, invoking an rcp or rsh command, using ftp, or using su. When an operation involves changing or setting an identity, a set of configurable modules is used to provide authentication, account management, credentials management, and session management.

For an overview of PAM, see Chapter 17, Using PAM, in System Administration Guide: Security Services.

Naming Services Configuration

Resource management supports naming service project databases. The location where the project database is stored is defined in the /etc/nsswitch.conf file. By default, files is listed first, but the sources can be listed in any order.

project: files [nis] [ldap]

If more than one source for project information is listed, the nsswitch.conf file directs the routine to start searching for the information in the first source listed, and then search subsequent sources.

For more information about the /etc/nsswitch.conf file, see Chapter 2, The Name Service Switch (Overview), in System Administration Guide: Naming and Directory Services (DNS, NIS, and LDAP) and nsswitch.conf(4).

Local /etc/project File Format

If you select files as your project database source in the nsswitch.conf file, the login process searches the /etc/project file for project information. See the projects(1) and project(4) man pages for more information.

The project file contains a one-line entry of the following form for each project recognized by the system:

projname:projid:comment:user-list:group-list:attributes

The fields are defined as follows:

projname

The name of the project. The name must be a string that consists of alphanumeric characters, underline (_) characters, hyphens (-), and periods (.). The period, which is reserved for projects with special meaning to the operating system, can only be used in the names of default projects for users. projname cannot contain colons (:) or newline characters.

projid

The project's unique numerical ID (PROJID) within the system. The maximum value of the projid field is UID_MAX (2147483647).

comment

A description of the project.

user-list

A comma-separated list of users who are allowed in the project.

Wildcards can be used in this field. An asterisk (*) allows all users to join the project. An exclamation point followed by an asterisk (!*) excludes all users from the project. An exclamation mark (!) followed by a user name excludes the specified user from the project.

group-list

A comma-separated list of groups of users who are allowed in the project.

Wildcards can be used in this field. An asterisk (*) allows all groups to join the project. An exclamation point followed by an asterisk (!*) excludes all groups from the project. An exclamation mark (!) followed by a group name excludes the specified group from the project.

attributes

A semicolon-separated list of name-value pairs, such as resource controls (see Chapter 6, Resource Controls (Overview)). name is an arbitrary string that specifies the object-related attribute, and value is the optional value for that attribute.

name[=value]

In the name-value pair, names are restricted to letters, digits, underscores, and periods. A period is conventionally used as a separator between the categories and subcategories of the resource control (rctl). The first character of an attribute name must be a letter. The name is case sensitive.

Values can be structured by using commas and parentheses to establish precedence.

A semicolon is used to separate name-value pairs. A semicolon cannot be used in a value definition. A colon is used to separate project fields. A colon cannot be used in a value definition.

Routines that read this file halt if they encounter a malformed entry. Any projects that are specified after the incorrect entry are not assigned.

This example shows the default /etc/project file:

system:0:System:::
user.root:1:Super-User:::
noproject:2:No Project:::
default:3::::
group.staff:10::::

This example shows the default /etc/project file with project entries added at the end:

system:0:System:::
user.root:1:Super-User:::
noproject:2:No Project:::
default:3::::
group.staff:10::::
user.ml:2424:Lyle Personal:::
booksite:4113:Book Auction Project:ml,mp,jtd,kjh::

You can also add resource controls and attributes to the /etc/project file:

• To add resource controls for a project, see Setting Resource Controls.

• To define a physical memory resource cap for a project using the resource capping daemon described in rcapd(1M), see Attribute to Limit Physical Memory Usage for Projects.

• To add a project.pool attribute to a project's entry, see Creating the Configuration.

Project Configuration for NIS

If you are using NIS, you can specify in the /etc/nsswitch.conf file to search the NIS project maps for projects:

project: nis files 

The NIS maps, either project.byname or project.bynumber, have the same form as the /etc/project file:

projname:projid:comment:user-list:group-list:attributes

For more information, see Chapter 4, Network Information Service (NIS) (Overview), in System Administration Guide: Naming and Directory Services (DNS, NIS, and LDAP).

Project Configuration for LDAP

If you are using LDAP, you can specify in the /etc/nsswitch.conf file to search the LDAP project database for projects:

project: ldap files

For more information about LDAP, see Chapter 8, Introduction to LDAP Naming Services (Overview/Reference), in System Administration Guide: Naming and Directory Services (DNS, NIS, and LDAP). For more information about the schema for project entries in an LDAP database, see Solaris Schemas in System Administration Guide: Naming and Directory Services (DNS, NIS, and LDAP).

Task Identifiers

Each successful login into a project creates a new task that contains the login process. The task is a process collective that represents a set of work over time. A task can also be viewed as a workload component. Each task is automatically assigned a task ID.

Each process is a member of one task, and each task is associated with one project.

Figure 2–1 Project and Task Tree

All operations on process groups, such as signal delivery, are also supported on tasks. You can also bind a task to a processor set and set a scheduling priority and class for a task, which modifies all current and subsequent processes in the task.

A task is created whenever a project is joined. The following actions, commands, and functions create tasks:

• login

• cron

• newtask

• setproject

• su

You can create a finalized task by using one of the following methods. All further attempts to create new tasks will fail.

• You can use the newtask command with the -F option.

• You can set the task.final attribute on a project in the project naming service database. All tasks created in that project by setproject have the TASK_FINAL flag.

For more information, see the login(1), newtask(1), cron(1M), su(1M), and setproject(3PROJECT) man pages.

The extended accounting facility can provide accounting data for processes. The data is aggregated at the task level.

Commands Used With Projects and Tasks

The commands that are shown in the following table provide the primary administrative interface to the project and task facilities.