GOI, POI, and TOI

You will start see three terms being used:

• GOI, which means Group of Interest
• POI, which means Process of Interest
• TOI, which means Thread of Interest

When the CLI executes a command, the arena decides the scope of what will run. It does not, however, determine what will run. Depending upon the command, the CLI looks determines what is the TOI, POI, or GOI, then executes upon that thread, process, or group. For example, you tell the CLI to step the current control group. In this case, it needs to know what the TOI is so it can determine what the lockstep group. (You can only step a lockstep group.) The lockstep group, which is a thread group, is part of a share group, which is a process group. This share group is part of a control group. So, know it know what the GOI is. This is important because, as you will see, while it now knows what it will step (the threads in the lockstep group), it also knows what it will allow to run freely while it is stepping these threads.

Using the GOI, POI, and TOI will become clearer as you read the rest of this chapter.