Redi2 - A High-Performance In-Memory Key-Value Store

Redi2 is a lightweight, high-performance in-memory key-value store written in C. It is designed to handle thousands of concurrent connections efficiently using a non-blocking I/O model with epoll on Linux.

It implements a subset of the Redis Serialization Protocol (RESP), making it compatible with standard Redis clients like redis-cli.

Features (MVP)

• Non-blocking I/O: Uses epoll for highly scalable event-driven networking.
• Concurrent Storage: A thread-safe hash table with fine-grained locking (lock striping) to minimize contention.
• RESP Compatible: Understands a subset of the Redis protocol.
• Core Commands: Implements PING, SET, GET, and DEL.

Requirements

• A Linux-based operating system (for epoll).
• gcc compiler.
• make build tool.
• redis-cli for testing (can be installed via redis-tools).

Build Instructions

To compile the project, navigate to the root directory and run make:

make

This will create the executable at bin/redi2.

Usage

1. Start the Server

Run the compiled executable to start the server. It will listen on the default port 6379.

./bin/redi2

To run on a different port, provide it as an argument:

./bin/redi2 9999

2. Connect with a Client

With the server running, open a new terminal and connect using redis-cli:

redis-cli -p 6379

Example Session

127.0.0.1:6379> PING
PONG
127.0.0.1:6379> SET mykey "Hello World"
OK
127.0.0.1:6379> GET mykey
"Hello World"
127.0.0.1:6379> DEL mykey
:1
127.0.0.1:6379> GET mykey
(nil)