This article explains how Redis master‑slave replication works, covering asynchronous copying, partial resynchronization, disk‑less replication, safety considerations when persistence is disabled, read‑only slaves, authentication, and configuration options such as slaveof and write‑restriction based on slave count.
The article examines two common MySQL master‑slave delay scenarios—slow ALTER operations and MyISAM table‑level locks—explains why they cause replication lag, and offers practical mitigation steps such as scheduling problematic SQL, isolating lagging slaves, and tuning binlog write settings.
The article explains Amazon’s Dynamo distributed key‑value store architecture, covering its decentralized design, consistent hashing with virtual nodes, replication strategies, quorum‑based read/write parameters, vector‑clock versioning, failure detection, hinted handoff, scaling mechanisms, and how these techniques together provide high availability, scalability, and reliability.
This article introduces NoSQL concepts, compares common storage models, and details MongoDB's replication architectures, special node roles, synchronization processes, and the variety of index types available for efficient data handling.
This article examines several MySQL issues—including key partition hash algorithm changes causing data loss after upgrades, a client crash triggered by misdirected dump output, GTID_PURGED interactions that break AUTO_POSITION replication, and replicate‑do‑db filtering effects on GTID continuity—and provides concrete compatibility fixes and troubleshooting steps.
This article provides a comprehensive guide to MySQL performance optimization, covering isolation levels, MVCC, schema design, index strategies, query execution, partitioning, replication, scaling, hardware considerations, and backup/recovery techniques for building high‑performance, reliable database systems.
This article examines why MySQL 5.5/5.6 fails to retrieve non‑null partitioned rows after a physical upgrade, how the ALTER TABLE … PARTITION BY KEY ALGORITHM=1 fix works, the cause of MySQL client crashes when dump output mixes warnings, GTID_PURGED replication bugs, replicate‑filter side effects, and the behavior of TokuDB’s OPTIMIZE TABLE.
This article explains MySQL's evolution from serialized binlog writes to group commit, introduces DDL fast‑fail and GTID allocation improvements, analyzes InnoDB auto‑increment duplication after restart, and details replication performance gains from multi‑threaded and seqno‑based parallel execution, providing code examples and benchmark results.
This article systematically explores the distributed characteristics of NoSQL databases, covering data consistency, placement, peer systems, anti‑entropy protocols, eventual consistency data types, sharding, fault detection, and coordinator election, illustrating how these strategies balance scalability, availability, latency, and fault tolerance.
This article explains why MySQL migrations are essential, outlines backup and restore strategies, and provides detailed, step‑by‑step procedures for multiple real‑world scenarios—including single‑master/slave moves, cross‑datacenter transfers, and multi‑instance setups—while highlighting key precautions and practical tips for successful execution.
This article explains why MySQL migration is essential, outlines various migration strategies—including full, partial, and cross‑datacenter moves—and provides detailed, step‑by‑step procedures, best‑practice tips, and precautionary measures to ensure a smooth, reliable transition.
This article reviews various MySQL high‑availability architectures—including master‑slave replication with keepalived or MHA, Galera‑based clusters, and other approaches—detailing their deployment methods, advantages, limitations, and practical considerations for selecting an appropriate HA solution.
DD Boost allows backup applications to manage and simplify file replication between multiple Data Domain systems, and using NetWorker as an example, the article details the step‑by‑step replication workflow, optional low‑bandwidth and encryption features, and how remote restores are performed.
This article discusses MySQL high‑availability solutions, covering asynchronous and semi‑synchronous replication, monitoring with keepalived, Zookeeper, and custom agents, failover procedures using binlog positions, GTID and pseudo‑GTID techniques, and the author's practical experiences and future plans.
This article outlines the four main types of MySQL physical files—system, log, replication, and data files—detailing their purposes and showing visual examples to help database administrators manage storage effectively and ensure optimal performance.
This article systematically explores the distributed characteristics of NoSQL databases, covering consistency trade‑offs, replication techniques, anti‑entropy protocols, data placement strategies, failure detection, and coordinator election, while illustrating each concept with diagrams and practical examples.
Redis uses both lazy and periodic deletion strategies to remove expired keys, balancing CPU usage and memory efficiency, and these strategies also affect how persistence mechanisms like RDB and AOF as well as master‑slave replication handle expired keys.
When read traffic overwhelms a single MySQL master, cascading replication and dual-master setups can distribute slave load, reduce replication lag, and simplify failover, offering a scalable solution that balances read/write pressure across multiple replication layers.
This article examines the problems and trade‑offs of metadata protection in cloud object storage, highlighting the importance of reliability, availability, and consistency, and comparing primary‑secondary and multi‑replica models, including the WRN algorithm and practical operational considerations.
An expert panel from the High‑Efficiency Operations community answers eleven pressing MySQL 5.7 questions, covering test hardware, GA timeline, GIS speed, virtual column indexing, materialized view plans, 2‑D geo support, performance monitoring, Oracle’s market strategy, geojson handling, multi‑source replication, buffer‑pool locking, and InnoDB Memcached consistency.
The article describes the evolution, architecture, automatic scaling, sharding, disaster‑recovery mechanisms, and strong synchronous replication strategy of TDSQL, a MySQL‑engine based distributed database built to meet the high‑availability and high‑consistency requirements of Tencent's billing platform.
This article presents 58.com’s experience with MySQL under massive data volumes, covering core concepts such as single‑instance, sharding, replication and grouping, common availability and read‑write challenges, detailed sharding implementations for user, post, friend and order tables, and post‑sharding business practices including IN queries, non‑partition key queries, and cross‑database pagination.
This article explains the fundamental reasons why MySQL slave servers experience higher latency than masters and provides practical optimization techniques—including parallel replication, proper indexing, I/O improvements, and hardware choices—to reduce replication lag.
This article explains a rare MySQL replication scenario where Seconds_Behind_Master stays at zero while the slave cannot receive updates, analyzes the underlying push‑based replication mechanism, and offers practical steps and configuration tweaks to detect and prevent the issue.
This article presents a comprehensive technical overview of MySQL performance tuning and feature enhancements—including group‑commit redesign, DDL fast‑fail, GTID handling, persistent auto‑increment, replication parallelism, and key‑partition hash changes—backed by real‑world test data from Taobao's large‑scale deployment.
This article highlights several often‑overlooked MongoDB limitations—including excessive disk‑space preallocation, a 12‑node replica‑set cap, lack of high‑availability in master‑slave mode, 32‑bit version constraints, high consulting fees, and weak management tools—helping developers avoid costly surprises.
