Computer Memory and Storage

Contiguous memory allocation places a process in a single continuous block of memory with consecutive addresses. This simplifies address translation but can lead to fragmentation. Non-contiguous allocation (like paging) allows a process to occupy non-adjacent blocks.

Wasted memory refers to the fraction of physical memory that remains unused due to internal or external fragmentation. This metric helps evaluate memory allocation efficiency. Lower wasted memory indicates better utilization of available physical memory.

Table fragmentation refers to the physical memory consumed by memory management data structures like page tables, segment tables, or allocation maps. This overhead is necessary for virtual memory translation but reduces available memory for actual processes.

Memory access overhead correctly describes the extra time spent on memory management operations like address translation, protection checks, and page table walks. Time complexity refers to algorithm analysis, while wasted memory refers to space inefficiency.

Memory partitioning can indeed be static (partitions fixed at system initialization) or dynamic (partitions created and sized as needed during runtime). Both approaches are valid memory management strategies.

First-fit allocation selects the first free partition that is large enough to accommodate the process. It's simple and fast but may lead to external fragmentation. Best-fit and worst-fit are alternative strategies.

The swapper allocates and manages swap space.

In this technique, there are some address dependent locations in the program and address constant must be adjusted according to allocate space.

This technique is used to locate a program in an appropriate area of the main storage of a computer when it is executed.

Swapping is the process of moving a suspended process from main memory to secondary storage (disk) and back. This allows the system to free up memory for other processes when RAM is limited.

In coincident-current core memory, each core is threaded by 4 wires: 2 X wires (row selection), 2 Y wires (column selection), plus sense and inhibit lines that can be shared. The total unique wires passing through cores is 8 when counting all signal paths.

Hard disks provide the fastest information retrieval among the options because they use spinning platters with movable read/write heads that can rapidly access any sector. Floppy disks are slower due to lower rotational speeds and mechanical limitations, while magnetic tape is sequential access only, making it the slowest for random retrieval.

Larger RAM reduces the need for frequent disk I/O operations because more data and programs can reside in fast memory. When RAM is insufficient, the system must swap data to disk (thrashing), which is significantly slower than RAM access. Eliminating frequent disk I/Os improves overall processing speed.

Volatile memory (RAM) loses its contents when power is turned off. Therefore, users must save important data to permanent storage (hard disk, SSD, or other non-volatile media) before shutting down. The CPU, ALU, and Control Unit are processing components, not storage destinations.