CPU Cache Simulation Library

Overview

This library simulates a cache memory module to demonstrate the basic operations of cache behavior, including cache hits, cache misses, eviction policies, and write operations. The goal is to model a simple cache system that can interact with a backing store (a text file) and track cache access history.

Specifications

Background

A cache is a temporary storage for data that allows faster access compared to its original storage, known as the backing store. Data is stored as key-value pairs, where the key serves as a unique identifier. The cache interacts with the agent (which could be a user or software) to provide data more efficiently.

• Cache hit: When the requested data is present in the cache.
• Cache miss: When the requested data is not in the cache, prompting the cache to access the backing store and store the data for future access.

Caches have limited capacity, so when a cache miss occurs, the cache may need to evict an existing entry to make room for the new data. This simulation follows a "least recently used" (LRU) replacement policy, where the least recently accessed data is evicted when the cache is full.

Goal

The primary goal is to simulate cache behavior, focusing on:

• Cache hits and misses
• Data retrieval and write operations
• Cache eviction policies (LRU)
• Tracking the number of cache misses during a sequence of accesses

Class Summary

The simulation is implemented with the following key classes:

• CacheItem: Represents a single data item in the cache, consisting of a key and its associated data.
• CacheResponse: A wrapper class that stores a CacheItem and provides additional metrics like whether the request was a cache hit or miss.
• Cache: The main class representing the cache, which holds CacheItem objects and implements cache management policies (LRU).
• CacheSim: Coordinates the simulation of cache accesses and maintains a history of cache states during the simulation.
• NotFoundException: An exception thrown when requested data is not found in the cache or backing store.

Tools Used

This project was developed using the following tools:

• Java: For writing the code and extending the code base.
• JUnit 5: For writing and executing unit tests to ensure the correctness of cache simulation logic.
• IntelliJ IDEA: As the integrated development environment (IDE) for coding, testing, and debugging the project.

Usage Instructions

Clone the repository:

git clone https://github.com/OmarMehanna/CPU-Cache-Simulation-Library.git