Redis: Your Guide to In-Memory Data Storage, Setup, and Usage (2024)

Redis is a powerful, open-source, in-memory data structure store, used as a database, cache, and message broker. This guide provides an overview of Redis, covering everything from basic concepts to installation and usage. Master Redis and dramatically improve your application performance.

What is Redis and Why Use It?

Redis stands out because it stores data in memory, enabling blazing-fast read and write operations. This makes it ideal for:

• Caching: Speed up applications by storing frequently accessed data in Redis.
• Real-time analytics: Process and analyze data streams in real-time.
• Session management: Store user session data for fast and reliable access.
• Queues: Implement message queues for asynchronous processing.
• Leaderboards: Create real-time leaderboards for games and applications.

Redis supports various data structures like strings, lists, sets, sorted sets, and hashes, offering flexibility for different use cases.

Supported Operating Systems

Redis is designed to run on multiple operating systems. The following operating systems are officially supported:

• Linux
• OSX
• OpenBSD
• NetBSD
• FreeBSD

Building Redis from Source: Quick Start Guide

Building Redis from source is straightforward. Follow these simple steps:

1. Open your terminal: Navigate to the directory where you've downloaded the Redis source code.

2. Run make: This command compiles Redis with default settings.

   % make
   

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3. Test the build (optional): Ensure everything is working correctly.

   % make test
   

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Building Redis with TLS Support

For enhanced security, build Redis with TLS support. You'll need OpenSSL development libraries.

1. Install OpenSSL: Use your system's package manager (e.g., apt-get install libssl-dev on Debian/Ubuntu).

2. Build with TLS enabled:

   % make BUILD_TLS=yes
   

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Building Redis with Systemd Support

To manage Redis as a systemd service:

1. Install systemd development libraries: (e.g., apt-get install libsystemd-dev on Debian/Ubuntu or yum install systemd-devel on CentOS).

2. Build with systemd support:

   % make USE_SYSTEMD=yes
   

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Troubleshooting Build Issues: make distclean

Encountering build problems? The make distclean command is your friend:

• Dependency issues: If dependencies aren't rebuilding after updates.
• Cached build options: When switching between 32-bit and 64-bit builds.

Run make distclean to clean everything and start fresh.

Specifying a Memory Allocator

Redis defaults to jemalloc on Linux for its superior memory fragmentation handling. To use the system's libc malloc:

% make MALLOC=libc

For macOS, force compilation against jemalloc using:

% make MALLOC=jemalloc

Running Redis

After building, run Redis using:

1. Navigate to the src directory:

   % cd src
   

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2. Start the Redis server:

   % ./redis-server
   

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To use a custom configuration file:

% ./redis-server /path/to/redis.conf

Command-line options override settings in the configuration file:

% ./redis-server --port 9999 --replicaof 127.0.0.1 6379

Interacting with Redis: The Redis CLI

The redis-cli is your command-line interface for interacting with Redis.

1. Start the CLI:

   % ./redis-cli
   

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2. Execute commands:

   redis> ping
   PONG
   redis> set foo bar
   OK
   redis> get foo
   "bar"
   

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Installing Redis System-Wide

To install Redis to /usr/local/bin:

% make install

For a different installation directory:

% make PREFIX=/some/other/directory install

To properly configure Redis as a system service on Ubuntu/Debian:

% cd utils
% ./install_server.sh

This script sets up init scripts and configuration files for automatic startup on boot. Note: This script is Linux-specific.

Contributing to Redis

Interested in contributing? All code contributions are subject to the Redis Software Grant and Contributor License Agreement. See the CONTRIBUTING.md file for more information.

Delving Into Redis Internals

The Redis source code is located in the src directory. Key components include:

• redis.c: The main server implementation.
• networking.c: Networking and event loop.
• t_string.c, t_list.c, t_hash.c, etc.: Implementations of different data types.

This guide gives you a solid foundation for understanding, installing, and using Redis. Explore the official Redis documentation for in-depth information and advanced features.