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.

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.

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.