The Linux Programming Interface

Process Priorities and Scheduling 737 if (argc != 4 || strchr("pgu", argv[1][0]) == NULL) usageErr("%s {p|g|u} who priority\n" " ...

738 Chapter 35 z A realtime application should be able to control the precise order in which its component processes are schedul ...

Process Priorities and Scheduling 739 Adding support for hard realtime applications is difficult to achieve without imposing an ...

740 Chapter 35 35.2.2 The SCHED_FIFO Policy The SCHED_FIFO (first-in, first-out) policy is similar to the SCHED_RR policy. The m ...

Process Priorities and Scheduling 741 For both system calls, policy specifies the scheduling policy about which we wish to obtai ...

742 Chapter 35 SUSv3 defines the param argument as a structure to allow an implementation to include additional implementation-s ...

Process Priorities and Scheduling 743 Listing 35-2: Modifying process scheduling policies and priorities ––––––––––––––––––––––– ...

744 Chapter 35 make arbitrary changes to the scheduling policy and priority of any process. How- ever, an unprivileged process c ...

Process Priorities and Scheduling 745 Upon successful execution, sched_getscheduler() returns one of the policies shown earlier ...

746 Chapter 35 Preventing realtime processes from locking up the system Since SCHED_RR and SCHED_FIFO processes preempt any lowe ...

Process Priorities and Scheduling 747 The SCHED_RESET_ON_FORK flag was designed to be used in media-playback applica- tions. It ...

748 Chapter 35 35.4 CPU Affinity When a process is rescheduled to run on a multiprocessor system, it doesn’t neces- sarily run o ...

Process Priorities and Scheduling 749 The sched_setaffinity() system call sets the CPU affinity of the process specified by pid. ...

750 Chapter 35 The following code confines the process identified by pid to running on any CPU other than the first CPU of a fou ...

Process Priorities and Scheduling 751 35.5 Summary The default kernel scheduling algorithm employs a round-robin time-sharing po ...

752 Chapter 35 35-3. Write a program that places itself under the SCHED_FIFO scheduling policy and then creates a child process. ...

Chapter 36: Process Resources Each process consumes system resources such as memory and CPU time. This chapter looks at resource ...

754 Chapter 36 The who argument specifies the process(es) for which resource usage information is to be retrieved. It has one of ...

Process Resources 755 Although getrusage() appears on most UNIX implementations, it is only weakly specified in SUSv3 (which spe ...

756 Chapter 36 The resource argument identifies the resource limit to be retrieved or changed. The rlim argument is used to retu ...