Απόκρυψη μικρών αλλαγών - Αλλαγές κώδικα
Αλλαγή σειρών 1-2 από:
Αλλαγή σειρών 7-9 από:
Αλλαγή σειρών 13-14 από:
Πρόσθεση σειρών 1-11:
Τι είναι διεργασία;
Several popular microcomputer operating systems provide little or no means of concurrent processing. Discuss the major complications that concurrent processing adds to an operating system.
- A method of time sharing must be implemented to allow each of several processes to have access to the system. This method involves the preemption of processes that do not voluntarily give up the CPU (by using a system call, for instance) and the kernel being reentrant (so more than one process may be executing kernel code concurrently).
- Processes and system resources must have protections and must be protected from each other. Any given process must be limited in the amount of memory it can use and the operations it can perform on devices like disks.
- Care must be taken in the kernel to prevent deadlocks between processes, so processes aren’t waiting for each other’s allocated resources.