CSC633 OPERATING SYSTEMSASSIGNMENT 1 (Weighting 15%)DUE DATE: 22/03/19-19685280035 Date: 22-3-2019 Total: 35 marks Define operating system. ( 1 mark)Operating system- is a computer program that manages the computer or allows the user to run applications on the computer. Example: keyboard, mouse, printer, and monitors. Explain with the help of a diagram the components of a computer system and their interactions. (5 marks)Input unit- is utilized for exchanges’ raw Data and control signals into the data handling framework by the client before preparing and calculation.
All the information unit gadgets give the guidelines and information is changed into parallel codes that are the essential memory adequate arrangement. Example: keyboard, mouse, scanner, joystick.Memory- data can be stored in computer before the data is retrieve for actual processing. Control unit- controls and organizes the activities of the considerable number of parts of the PC framework. It reads information from the memory, decodes the directions, takes care of its execution, and gets the following guidance.Output unit- It controls different kinds of output like printer, realistic plotter, discourse synthesizer, screen (otherwise called Visual Display Unit or VDU) to create the ideal output and present it to the client.
It guarantees the convertibility of output into intelligible structure that is justifiable by the client.Arithmetic logic unit (ALU) – performs arithmetical estimations and calculations like expansion, subtraction, augmentation and division. It is likewise in charge of legitimate counts like comparisons among information things. What is the purpose of interrupts? How does an interrupt differ from a trap? Can traps be generated intentionally by a user program? If so, for what purpose? (3marks)An interrupt is computer hardware to change of stream inside the system. An interrupt on handler is brought to manage the reason for interfere with the control. Control is then returned back to the interrupter on the setting and guidance. A trap is a product created interface. An interrupter can utilize to flag and finish of an I/O to forestall the requirement of the gadget surveying. A trap can be utilized to call working framework schedules or get arithmetic errors.Describe some of the challenges of designing operating systems for mobile devices compared with designing operating systems for traditional PCs. (2 marks)Operating system should manage the battery life carefully of the PC. The mobile devices should be increasingly more identified with individual’s protection, so the security of working framework for the mobile device tallies much more than the conventional PCs and harder to avoid harmful code and access. What are the functions of an operating system? List and describe each in detail. (5 marks)Data security- the operating system in the computer should protect the data which is stored on the computer by the users from malicious purpose or deletion.Disk management- the operating system should manage and store data in a proper way. Booting- the operating system should check the computer and ready to be use by the users. Loading and execution- the operating system should load the programs in the memory and then then accomplish it. Process management- Central Processing Unit (CPU) can perform one assignment at one time. In the event that numerous errands, working framework chooses which task to get done first.Discuss three common ways of establishing relationship between the user and kernel thread? (1mark)User level thread Kernel level thread The user level threads are supported above by the kernel level thread and are apply by thread library at the user level. The kernel level thread is supported by the operating system. User level threads are normally quick to create and run. Kernel level threads are slow and ineffective. For example: kernel level thread is hundreds of times slower than the user level thread. Example: Mach C-threads, POSIX Pthreads Example: Windows NT, Windows 2000Consider the FCFS, SJF, and RR (quantum = 10 milliseconds) scheduling algorithms for this set of processes. Which algorithm would give the minimum average waiting time? 6mksProcess Burst TimeP1 10P2 29P3 3P4 7P5 12The processes are assumed to have arrived in the order P1, P2, P3, P4, P5,all at time 0.Draw four Gantt charts that illustrate the execution of these processes using the following scheduling algorithms: FCFS, SJF,and RRWhat is the waiting time of each process for each of these scheduling algorithms?Which of the algorithms results in the minimum average waiting time (over all processes)? FCFSP1 P2 P3 P4 P5 0 10 39 42 49 61Waiting time= start time ” arrival time P1- 0-0=0P2- 10-0=10P3- 39-0=39P4- 42-0=42P5- 49-0=49Average waiting time= (0+10+39+42+49) 5 =28SFJP3 P4 P1 P5 P2 0 3 10 20 32 61P1- 10-0=10P2- 32-0=32P3- 0-0=0P4- 3-0=3P5- 20-0=20Average waiting time= (10+32+0+3+20) 5 =13RRP1 P2 P3 P4 P5 P2 P5 P2 0 10 20 23 30 40 50 52 61P1- 0-0=0P2- (10-0)+(40-20)+(52-50)=10+20+2=32P3- 20-0=20P4- 23-0=23P5- (30-0)+(50-40)=30+10=40Average waiting time= (0+32+20+23+40) 5 =23Therefore SJF algorithm is having the minimum average waiting time (over all processes).For the following questions use Text book as well as you can browse Internet What are the possible states that a thread can be in? (1 mark)NewRunnable RunningBlocked Terminated Which function is used to put a thread to sleep? (1 mark)Thread.sleep() As described in Section 4.7.2, Linux does not distinguish between processes and threads. Instead, Linux treats both in the same way, allowing a task to be more akin to a process or a thread depending on the set of flags passed to the clone() system call. However, other operating systems, such as Windows, treat processes and threads differently. Typically, such systems use a notation in which the data structure for a process contains pointers to the separate threads belonging to the process. Contrast these two approaches for modeling processes and threads within the kernel (3 marks)On one hand, in frameworks where procedures and strings are considered as comparative substances, a portion of the working framework code could be extra. A scheduler, for example, can consider the typical procedures and strings in equivalent balance without requiring exceptional code to look at the strings related with a procedure amid each planning venture. Then again, this consistency could make it harder to force process-wide asset limitations in an immediate way. Rather, some additional intricacy is required to differentiate which strings relate to which process and play out the important bookkeeping undertakings.How does multiprogramming increase the utilization of resources? (1 mark)Increases the utilization of CPU It maximizes the throughput Explain what a race condition is. You may use everyday examples to illustrate your point (3 marks).Race condition is a condition when different threads are getting to shared memory in indefinite request, and when somewhere around one access is for “express” for example changing the memory content”.List and explain the synchronization problems (3 marks).Bounded buffer problem ” where a finite buffer pool is utilized to trade messages among producer and customer forms. Since the buffer pool has a greatest size, this is frequently called bounded buffer problem. Reader writer problem- in this situation, readers only read the shared data and never being changed whereas writer can change the data instead on reading it. Dining philosopher’s problem- concern includes the allocation of resources of gathering of procedures in a deadlock-free and starvation way. ReferenceGoogle.com. (2019). components of computer system and its function – Google Search. [online] Available at: [Accessed 16 Mar. 2019].Anon, (2019). [online] Available at: [Accessed 16 Mar. 2019].