Correct Answer: Hard real-time systems required to complete a critical task within a guaranteed amount of time Soft real-time computing requires that critical processes receive priority over less fortunate ones
Correct Answer: In order to protect the operating systems and the system programs from the malfunctioning programs the two mode operations were evolved System mode User mode
Correct Answer: Mutex is a program object that allows multiple program threads to share the same resource, such as file access, but not simultaneously When a program is started a mutex is created woth a unique name After this stage, any thread that needs the resource must lock the mutex from other threads while it is using the resource the mutex is set to unlock when the data is no longer needed or the routine is finished
Correct Answer: Deadlock is a situation where a group of processes are all blocked and none of them can become unblocked until one of the other becomes unblocked The simplest deadlock is two processes each of which is waiting for a message from the other
Correct Answer: Transferring the control from one process to other process requires saving the state of the old process and loading the saved state for new process This task is known as context switching
8. What is DRAM? In which form does it store data?
Correct Answer: DRAM is not the best, but it?s cheap, does the job, and is available almost everywhere you look DRAM data resides in a cell made of a capacitor and a transistor The capacitor tends to lose data unless it?s recharged every couple of milliseconds, and this recharging tends to slow down the performance of DRAM compared to speedier RAM types
9. What is the state of the processor, when a process is waiting for some event to occur?
Correct Answer: Main memory - only large storage media that the CPU can access directly Secondary storage - extension of main memory that provides large nonvolatile storage capacity