Explain Cache Memory and Deadlocks in Operating Systems.

You're on a roll — let's solve these questions. Computer Science Revision A) Cache Memory: A cache memory is used to reduce the average memory access time by storing frequently accessed data closer to the CPU. When the CPU needs data, it first checks the cache. If the data is found (a cache hit), it's retrieved much faster than from main memory. If not (a cache miss), the data is fetched from main memory and a copy is placed in the cache for future use. Deadlocks (June 2015 P8al) a) What is Deadlock? A deadlock is a situation in an operating system where two or more processes are permanently blocked because each process is waiting for a resource that is held by another process in the same set. b) Explain the conditions necessary for deadlocks to occur in Operating Systems. For a deadlock to occur, all four of the following conditions must hold simultaneously: • Mutual Exclusion: At least one resource must be held in a non-sharable mode, meaning only one process can use it at a time. • Hold and Wait: A process holding at least one resource is waiting to acquire additional resources held by other processes. • No Preemption: Resources cannot be forcibly taken from a process; they can only be released voluntarily by the process holding them. • Circular Wait: A set of processes \P_0, P_1, , P_n\ exists such that P_0 is waiting for a resource held by P_1, P_1 is waiting for a resource held by P_2, ..., P_n-1 is waiting for a resource held by P_n, and P_n is waiting for a resource held by P_0. c) List any two causes of process termination in Operating Systems. Two causes of process termination are: • Normal Exit (Voluntary): The process completes its execution and terminates itself. • Error Exit (Voluntary): The process encounters an error (e.g., division by zero, invalid file access) and terminates itself. • Fatal Error (Involuntary): An error occurs that the process cannot handle, often due to hardware error or an invalid memory access, leading the operating system to terminate it. • Killed by another process (Involuntary): Another process (e.g., a parent process or an operating system process) explicitly terminates the process. Database Concepts What is a database? A database is an organized collection of structured information, or data, typically stored electronically in a computer system. It is designed for efficient storage, retrieval, and management of data. Primary Key A primary key is a column or a set of columns in a relational database table that uniquely identifies each row (or record) in that table. It must contain unique values and cannot have NULL values. Candidate Key A candidate key is a minimal set of attributes (columns) in a table that can uniquely identify each tuple (row) in that table. A table may have multiple candidate keys, and one of them is chosen as the primary key. Send me the next one 📸