Redis

Redis is an in-memory data store used as a database, cache, and message broker. It is open source and stores data in key-value pairs. Redis stands for Remote Dictionary Server. It was created in 2009 by Salvatore Sanfilippo and has become widely used for fast data access.

Unlike traditional databases that store data on disk, Redis keeps all data in memory. This makes it much faster for certain tasks. It is often used in web hosting, large-scale web applications, and systems that need high-speed data access.

History and Background

Redis began as a personal project by Salvatore Sanfilippo, who needed a faster solution for real-time analytics at an Italian startup. Existing tools were too slow, so he created a new system from scratch using the C programming language for maximum speed and efficiency.

Key milestones and features in Redis development:

• Initial release in 2009
• Designed to use memory as the main storage layer for speed
• Supported a rich set of data structures from the start:
  • Strings
  • Lists
  • Sets
  • Hashes
  • Sorted sets
• Differentiated itself from other key-value stores by supporting complex data types
• Maintained simplicity while delivering high performance

As Redis gained popularity, more features were added:

• Replication for data distribution
• Persistence to disk for durability
• High availability through features like Redis Sentinel

In 2015, Redis Labs (now Redis Inc.) became the official sponsor of the project, ensuring long-term development and enterprise support.

Redis vs Previous Storage Tools

Before Redis, developers often used relational databases like MySQL or PostgreSQL. These were good at storing large amounts of structured data on disk. They followed strict rules and used SQL to query data.

Redis is different in several ways:

• Redis stores all data in memory, not on disk by default
• Redis uses a key-value model, not a table model
• Redis supports many data types, not just strings
• Redis focuses on speed, not on full transaction support

Other systems like Memcached also store data in memory, but Redis offered more features. It allowed complex operations on stored data without needing external logic. This made it more useful for caching, queuing, and storing session data.

Key Features and Concepts

Redis has several features that make it useful in web hosting and application development.

• In-Memory Storage - Redis keeps all active data in memory. This means reading and writing data is much faster than with disk-based systems. It is often used for caching results from slower databases.
• Data Structures - Redis supports different data types. These include:
  • Strings
  • Lists
  • Sets
  • Sorted Sets
  • Hashes
  • Streams
  • Bitmaps
  • HyperLogLogs
  • Geospatial Indexes
  This range of data types allows Redis to solve different problems without needing extra tools.
• Persistence - Although Redis stores data in memory, it can save data to disk. This protects data in case of a system restart. Redis supports two types of persistence:
  • RDB snapshots: Save data at set intervals
  • AOF logs: Save each write operation in a log file
  You can use one, both, or neither based on your needs.
• Replication - Redis supports master-replica replication. A master node can have one or more replicas. This helps scale reads and improves availability. Replicas can also be promoted to master if needed.
• High Availability - Redis Sentinel manages high availability. It monitors master and replica nodes. If a master fails, Sentinel can promote a replica and redirect traffic. This helps prevent downtime.
• Clustering - Redis Cluster lets you split data across multiple nodes. It uses a slot-based approach to balance data. This helps scale writes and manage larger datasets. Redis Cluster also provides automatic failover.
• Pub or Sub Messaging - Redis supports publish or subscribe messaging. Clients can subscribe to channels. When a message is published to a channel, all subscribers receive it. This helps build real-time systems like chat apps or live dashboards.

Common Use Cases

Redis is often used in places where speed matters more than complex queries. Some common uses include:

• Caching - Redis is widely used for caching. It stores the results of slow database queries or API responses. When a user requests the same data, Redis returns it faster.
• Session Storage - Web applications use Redis to store user session data. This allows fast lookups and supports large numbers of users at the same time.
• Real-Time Analytics - Redis stores counters, scores, and time-based data. Applications use it to track metrics and user behavior in real time.
• Message Queues - With lists or streams, Redis can act as a message queue. It stores messages and allows workers to pull them in order. This helps process background jobs.
• Leaderboards - Using sorted sets, Redis helps create ranked lists. Game apps use this for scoring systems where users are ranked by performance.
• Rate Limiting - Redis can store counters that reset over time. This supports limits like login attempts or API usage per user.

Advantages of Redis

Redis offers several benefits to developers, hosting providers, and users. Its speed and flexibility help in many areas.

• Speed - Redis performs operations in memory. This gives response times measured in microseconds. It is much faster than disk-based databases.
• Simple Design - Redis uses a key-value model. This makes it easy to understand and quick to develop against. Developers do not need complex schemas or migrations.
• Rich Data Types - Redis supports more than just strings. Lists, sets, and other types let developers store and manage data more naturally. These types reduce the need for extra code in applications.
• Flexible Persistence - Redis lets you choose how to store data. You can enable disk writes for durability or disable them for pure speed.
• High Availability - With replication, Sentinel, and clustering, Redis can stay available during failures. Hosting providers can use these tools to build reliable services.
• Broad Ecosystem - Redis has drivers for many programming languages. Tools like Laravel, Django, and Node.js all support it. Hosting platforms often include Redis support as part of premium plans.

Redis with NTC Hosting

In web hosting, Redis plays a key role in speeding up websites and reducing load and MySQL queries. CMS platforms like WordPress and Magento can use Redis to cache pages and sessions.

With NTC Hosting, you will find that Redis is included with most of our cloud hosting packages and with all semi-dedicated, VPS, and dedicated servers that use the Hepsia Control Panel.

Enable Redis to get a significant speed improvement without changing any code on your website.