HybridCacheSystem

HybridCacheSystem is a modular and efficient caching framework written in modern C++. It provides a ready-to-use foundation for building high-performance, multi-layered cache systems, featuring classic algorithms like LRU (Least Recently Used) and LFU (Least Frequently Used) as well as an extensible multi-level queue for advanced scenarios. The core CacheManager component orchestrates these policies, making it easy to combine and customize cache behavior for complex applications.

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Project Structure

include/
│   CacheManager.h       # Interface for a unified cache manager
│   LFUCache.h           # Header for LFU (Least Frequently Used) cache
│   LRUCache.h           # Header for LRU (Least Recently Used) cache
│   MultiLevelQueue.h    # Header for multi-level queue, supporting hybrid/multi-tier caching
src/
│   CacheManager.cpp     # Implementation of the cache manager logic
│   LFUCache.cpp         # Implementation of LFU cache
│   LRUCache.cpp         # Implementation of LRU cache
│   MultiLevelQueue.cpp  # Implementation of multi-level queue
│   main.cpp             # Entry point with interactive demo
tests/
│   test_lru.cpp         # Example unit test for LRUCache
.github/
│   workflows/
│       ci.yml           # GitHub Actions workflow for CI/CD

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Getting Started

Prerequisites

• C++17 compatible compiler (e.g., g++ 7+, clang 6+, MSVC 2017+)
• CMake 3.10 or newer (for recommended build)
• Standard C++ STL (no external dependencies)

Build Instructions

git clone https://github.com/zennyMe17/HybridCacheSystem.git
cd HybridCacheSystem
mkdir build && cd build
cmake ..
make

This will generate an executable (typically HybridCacheSystem or main) in the build directory.

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Automation & Continuous Integration

This project uses GitHub Actions for automatic building and testing.
Every push and pull request to main or master will trigger an automated build and run the unit tests.

• The workflow checks out your code, installs dependencies, configures with CMake, builds, and runs all unit tests with CTest.
• To add more tests, simply add .cpp test files in the tests/ directory and update CMakeLists.txt accordingly.

Workflow badge:

![CI](https://github.com/zennyMe17/HybridCacheSystem/actions/workflows/ci.yml/badge.svg)

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How It Works

HybridCacheSystem allows you to:

• Use LRU or LFU as standalone caches for fast memory-based key-value storage.
• Combine multiple cache strategies using the MultiLevelQueue for advanced, tiered caching (e.g., hot/cold data separation).
• Centrally manage all cache operations (set, get, evict, stats) using CacheManager, which abstracts away the underlying policy.

Main Components

LRUCache
Evicts the least recently accessed items first. Useful for workloads where recent access is a strong predictor of future use.

LFUCache
Evicts the least frequently accessed items. Ideal for workloads with frequently repeating keys.

MultiLevelQueue
Supports multi-tier caching (e.g., combining RAM and SSD, or different cache policies). Can be configured to cascade evictions across levels.

CacheManager
Unified entry point for cache operations. Can be configured to use any combination of the above caches. Handles cache lookup, insertion, eviction, and statistics.

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Advanced Topics

• Multi-level caching: Use MultiLevelQueue to combine fast (RAM) and slow (disk) caches for maximum efficiency.
• Eviction tuning: Adjust cache sizes and policies to suit your application's data access patterns.
• Thread safety: Current implementation is single-threaded; for multi-threaded use, wrap cache operations with mutexes.

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Contributing

• Issues and pull requests are welcome!
• Please open an issue to discuss bugs or feature requests.
• Follow consistent C++ style and document your code.

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Happy caching and learning!