INtime® 3.1 Software - tenAsys

Chapter 3: About INtime software’s RT kernel
• Isolate resources for their threads, particularly for dynamically allocated memory.
Two threads of one process compete for the memory associated with their process.
Threads in different processes typically do not.
• Provide error boundaries. Errors within one process do not corrupt other processes
or the OS because they reside in separate virtual address spaces.
• When you delete processes, the objects associated with them also are deleted.
Each INtime application’s executable loads as a separate, loadable process. The
processes in a system form a process tree. Each application process obtains resources
from the root:
Figure 3-1. Processes in a process tree
Root
process
C library
Paging
subsystem
DSM
User
Process 1
User
Process 2
User
Process n
Virtual memory
The RT Application Loader creates RT processes when an INtime application loads.
There are system calls you can use to delete RT processes from within an application.
Each process has an associated VSEG whose size is the amount of Virtual Memory
available to the process. The VSEG size must be large enough to contain all the
memory dynamically allocated by the threads within the process.
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