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What is Redis Redis is a high‑performance, in‑memory key‑value database that also supports optional data persistence. It is open‑source and written in C, widely used both as a cache and as a primary datastore for specialised scenarios. Why Redis Is So Fast In‑memory storage – data is served directly from RAM, avoiding disk I/O for most operati ...

Cache Anomalies Cache Penetration: Requested data does not exist in the system. Use a Bloom filter. Cache Breakdown: A hot key expires. Implement mutual exclusion locks. Apply logical expiration (no actual TTL set). Cache Avalanche: Numerous keys expire simultaneously. Assign random expiration times. Deploy a Redis cluster. Cache Pen ...

Creating Lists LPUSH The LPUSH command adds one or more elements to the beginning of a list. 127.0.0.1:6379> lpush mylist item0 item1 item2 (integer) 3 127.0.0.1:6379> lrange mylist 0 3 1) "item2" 2) "item1" 3) "item0" 127.0.0.1:6379> lpush mylist item3 (integer) 4 127.0.0.1:6379> lrange mylist 0 4 1) & ...

SMS-Based Authentication Sending Verification Codes via Session When a user submits a phone number, the system validatse its format. If invalid, an error is returned. If valid, a verification code is generated, stored in the session, and sent via SMS. Login and Registration Flow The user inputs the code and phone number. The backend retrieves t ...

Docker Compose Overview Docker Compose is a powerful tool designed to define and manage multi-container Docker applications. When dealing with complex setups involving multiple services like Spring Boot applications, Redis, and MySQL, managing each container individually becomes cumbersome. Instead of manually configuring IP addresses and conne ...

User Registration Interface Image Code Verification Endpoint (Returns JPG Image) The UUID generation occurs automatically when the page loads. This implementation has been resolved by generating the UUID via JavaScript on page initialization. Endpoint: /api/v1_0/image_codes/{image_code_id} The image_code_id parameter is a UUID generated on the ...

Understanding Caching Concepts Buffer vs. Cache buffer: Primarily used for write operations, acting as a write buffer. cache: Primarily used for read operations, serving as a read cache. Both address speed inconsistencies and involve I/O operations. Key Cache Considerations 1. Storage location (multi-level cache): Client-side (browser cach ...

Overview This article describes a clean approach to implementing distributed locking and rate limiting using Redis in Spring Boot applications. The solution leverages Redis atomic operations for thread-safe state management across multiple service instances. Why Redis? Redis provides atomic operations that guarantee complete execution or no exe ...

Distributed Caching Architectures Handling Data Discrepancies Cache Penetration: Occurs when queries request data existing neither in the cache nor the database. Mitigation strategies include: Storing null values for missing keys with short expiration times to prevent redundant DB hits. Implementing a Bloom Filter to probabilistically verify d ...

Enviroment Preparation Server Layout Hostname IP Instances Ports redis-node-0 10.10.101.29 2 6379, 6380 redis-node-1 10.10.101.30 2 6379, 6380 redis-node-2 10.10.101.31 2 6379, 6380 Build Dependencies # Enable GCC 9 yum -y install centos-release-scl yum -y install devtoolset-9-gcc devtoolset-9-gcc-c++ devtoolset-9-binutils scl ena ...