IT 4 C Lab Quiz G2

Deadlock detection is a mechanism used to identify and resolve deadlocks in a system. When deadlock detection is implemented, it checks for the existence of deadlocks by examining the allocation of resources to different processes. In this context, the correct answer suggests that requested resources are granted to processes. This means that when a process requests a resource, it is allocated to that process if it is available. This helps in preventing deadlocks by ensuring that resources are distributed efficiently and effectively among the processes.

Deadlocks occur when multiple processes or threads are unable to proceed because each is waiting for a resource that another process holds. This situation arises when conflicting needs for resources arise, meaning that multiple processes require the same resource to complete their tasks. In this context, the correct answer is "Resources" because deadlocks involve conflicts over resource allocation.

The hit ratio refers to the percentage of times a page number is found in the Translation Lookaside Buffer (TLB). This means that when a page number is requested, if it is already present in the TLB, it is considered a hit. The hit ratio helps measure the efficiency of the TLB in reducing the number of memory accesses required for page translations. A higher hit ratio indicates better TLB performance, as more page translations can be retrieved from the TLB without accessing the main memory.

The scheduling of threads is done by the operating system. The operating system is responsible for managing and allocating system resources, including CPU time, to different threads in order to ensure efficient and fair execution of multiple threads concurrently. The operating system uses scheduling algorithms to determine the order in which threads are executed, taking into account factors such as thread priority, time quantum, and the state of the system. By controlling the scheduling of threads, the operating system can optimize resource utilization and provide a responsive and efficient environment for running multiple threads.

The correct answer is "State". The question is asking for the term that describes the current condition of a process that is currently executing. "State" is the most appropriate term to describe this as it refers to the current status or condition of a process.

No preemption means that a resource is released voluntarily. This means that the resource is not forcefully taken away or terminated, but rather it is willingly released by the entity that is currently using it.

Cache memory is designed to provide the fastest memory access compared to other types of memory. It is a small, high-speed memory that stores frequently accessed data and instructions closer to the CPU. This proximity allows the CPU to quickly retrieve the data it needs, reducing the time spent waiting for data from slower main memory or storage devices. Therefore, cache memory is considered the fastest option for memory access.

Once deadlock has been detected, a strategy for recovery is needed. Deadlock occurs when two or more processes are unable to proceed because each is waiting for the other to release a resource. To resolve deadlock, a recovery strategy is required to break the deadlock and allow the processes to continue execution. This strategy may involve techniques such as resource preemption, where resources are forcibly taken from one process and given to another, or process termination, where one or more processes involved in the deadlock are terminated to free up resources.

The SSTF algorithm, like the SJF algorithm, may cause starvation of some requests. This means that certain requests may be continuously overlooked or delayed indefinitely, leading to a lack of fairness in the allocation of resources. This can occur when there is a constant influx of new requests that have shorter seek times, causing older requests to be constantly pushed back and potentially never serviced.

Each entry in a segment table has a segment base. The segment base is the starting address of the segment in the memory. It is used to calculate the physical address of a memory location by adding the offset of the location within the segment to the segment base. This allows for efficient memory management and address translation in a segmented memory system.

The correct answer is System Call Interface. System call routines are mostly written in the System Call Interface. This interface provides the necessary functions and methods for the user processes to interact with the operating system. It acts as a bridge between the user processes and the kernel of the operating system, allowing the processes to request services from the kernel through system calls. The system call interface provides a set of functions that abstract the low-level operations of the operating system, making it easier for the user processes to perform various tasks and access system resources.

Deadlock avoidance is a technique used to prevent the occurrence of deadlocks in a system. It involves carefully managing resources and processes to ensure that deadlocks do not occur. To effectively avoid deadlocks, it is necessary to have knowledge of the future behavior of processes and their resource requirements. By analyzing the potential resource requests and releases of processes, it becomes possible to schedule and allocate resources in a way that avoids deadlock situations. Therefore, having knowledge of the processes is crucial for successful deadlock avoidance.

The maximum number of frames per process is defined by the amount of available physical memory. This is because each process requires a certain amount of memory to store its instructions and data. If there is not enough physical memory available, the system may need to use virtual memory techniques such as paging or swapping to compensate for the lack of physical memory. The operating system and instruction set architecture may also play a role in determining the maximum number of frames per process, but ultimately it is the amount of available physical memory that sets the limit.

The correct answer is Monolithic Kernel. The system structure of Linux is based on a monolithic kernel. In a monolithic kernel, all the operating system services such as process management, memory management, and device drivers are present in a single kernel space. This design allows for efficient communication between the different components of the operating system. Unlike a microkernel, which separates these services into user space and kernel space, a monolithic kernel provides faster performance but may be less modular and more prone to crashes.

Remote Procedure Calls (RPCs) are a communication mechanism used in client-server systems. It allows a program on one computer to execute a procedure on a remote computer. RPCs provide a high-level abstraction for interprocess communication and make it easier for developers to create distributed applications. This mechanism enables client-server systems to communicate and exchange data efficiently and securely. Therefore, RPCs are a suitable explanation for the given correct answer.

Secondary storage is the primary element used for data storage because it refers to devices and media that are external to the computer's main memory. This includes hard drives, solid-state drives, optical drives, and external storage devices. Unlike main storage (RAM) which is volatile and loses data when the computer is turned off, secondary storage retains data even when the power is off. It provides a large capacity for long-term storage of files, documents, programs, and other data. Therefore, secondary storage is considered the primary element for data storage.

The minimum number of frames to be allocated to a process is decided by the instruction set architecture. The instruction set architecture determines the size and format of instructions that a processor can execute. It also determines the maximum amount of memory that the processor can address. Therefore, the instruction set architecture plays a crucial role in determining the minimum number of frames required for a process, as it dictates the memory requirements and addressing capabilities of the processor.

In a single processor system, the implementation of semaphores can be inhibited through interrupts. Interrupts are signals sent by hardware or software to the processor to indicate the occurrence of an event that requires immediate attention. When an interrupt occurs, the processor suspends its current task and starts executing an interrupt handler. During this time, the execution of semaphore operations can be temporarily halted, preventing any potential deadlock situations. Interrupts allow for efficient multitasking and the handling of asynchronous events in a single processor system.

SCAN is the correct answer because in the SCAN algorithm, the disk arm starts at one end of the disk and moves towards the other end, servicing requests along the way. When it reaches the other end, the direction is reversed and servicing continues in the opposite direction. This algorithm is commonly used for disk scheduling to efficiently service requests and reduce the average seek time.

If there are 32 segments, each of size 1Kb, then the logical address should have 13 bits. This is because with 32 segments, we need enough bits to uniquely identify each segment. Since 2^5 = 32, we need 5 bits to represent the segment number. Therefore, the logical address should have 13 bits in total.