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Big Data Technology Tribe
Big Data Technology Tribe
Feb 25, 2026 · Databases

How Lance Implements MVCC Transactions with Optimistic Concurrency and Automatic Conflict Resolution

Lance uses Multi-Version Concurrency Control to provide ACID guarantees, creating immutable table versions on each commit and employing atomic storage primitives, rebase logic, and retry mechanisms to handle concurrent writes, conflict detection, and resolution across multiple transaction types.

Concurrency ControlDatabase InternalsLance
0 likes · 16 min read
How Lance Implements MVCC Transactions with Optimistic Concurrency and Automatic Conflict Resolution
Aikesheng Open Source Community
Aikesheng Open Source Community
Sep 10, 2025 · Databases

Why SELECT … FOR UPDATE Still Reads the Primary Key: MySQL Index Scan Deep Dive

This article examines why a SELECT … FOR UPDATE query that appears to use a covering index in MySQL actually performs a table‑row lookup, detailing indirect evidence from performance_schema locks and direct proof through InnoDB source code, and explains the necessity of accessing the primary key for transaction isolation.

Database InternalsIndex ScanInnoDB
0 likes · 9 min read
Why SELECT … FOR UPDATE Still Reads the Primary Key: MySQL Index Scan Deep Dive
Tech Freedom Circle
Tech Freedom Circle
Jul 17, 2025 · Databases

What Happens Under the Hood When a Redis Command Executes? – A Deep Dive into Redis’s Reactor Model

This article explains the three‑stage execution flow of a Redis command—connection establishment, command processing, and result return—detailing how the single‑threaded reactor pattern drives event handling, how commands are parsed and dispatched, and how the output is sent back, with code snippets and a comparison to Netty’s multithreaded reactor.

Command ExecutionDatabase InternalsI/O Multiplexing
0 likes · 50 min read
What Happens Under the Hood When a Redis Command Executes? – A Deep Dive into Redis’s Reactor Model
Aikesheng Open Source Community
Aikesheng Open Source Community
Feb 18, 2025 · Databases

Parsing Delete Undo Log in MySQL 8.0.32 InnoDB

This article explains how to read and parse the Undo log generated by a DELETE operation in MySQL 8.0.32 InnoDB, covering preparation, log extraction, detailed field parsing, locating the primary index record, and the step‑by‑step rollback of secondary and primary index records.

Database InternalsInnoDBmysql
0 likes · 10 min read
Parsing Delete Undo Log in MySQL 8.0.32 InnoDB
Aikesheng Open Source Community
Aikesheng Open Source Community
Feb 12, 2025 · Databases

Understanding the Delete Undo Log Format in MySQL 8.0 InnoDB

This article explains how MySQL 8.0 InnoDB generates and stores Delete Undo logs, detailing the log structure, field meanings, type_flag and info_bits decoding, address composition via DB_ROLL_PTR, and provides concrete SQL examples and shell calculations to illustrate the process.

Database InternalsDelete OperationInnoDB
0 likes · 11 min read
Understanding the Delete Undo Log Format in MySQL 8.0 InnoDB
Aikesheng Open Source Community
Aikesheng Open Source Community
Jan 8, 2025 · Databases

How InnoDB Performs Undo Log Rollback and Record Deletion

This article explains the complete InnoDB undo‑log rollback process on MySQL 8.0, covering preparation, reading and parsing undo logs, constructing primary‑key index records, and the detailed steps for deleting secondary and primary index entries during a transaction rollback.

Database InternalsInnoDBmysql
0 likes · 12 min read
How InnoDB Performs Undo Log Rollback and Record Deletion
Aikesheng Open Source Community
Aikesheng Open Source Community
Nov 27, 2024 · Databases

Summary of InnoDB Lock Module Articles

This article provides a concise English recap of the 27 previously published InnoDB lock module articles, covering theoretical concepts such as table and row locks, lock waiting, deadlock handling, and practical scenarios like lock behavior during inserts and duplicate key operations.

Database InternalsInnoDBLocks
0 likes · 6 min read
Summary of InnoDB Lock Module Articles
ITPUB
ITPUB
Nov 11, 2024 · Databases

When Does MySQL Actually Update Index Blocks? A Deep Dive into InnoDB Update Mechanics

This article examines how MySQL InnoDB decides whether to modify index blocks during UPDATE statements, walks through the internal mysql_update workflow, shows debugging with GDB, explains three test scenarios, and validates the behavior by inspecting block LSNs with the innblock tool.

Database InternalsIndex UpdateInnoDB
0 likes · 18 min read
When Does MySQL Actually Update Index Blocks? A Deep Dive into InnoDB Update Mechanics
Alibaba Cloud Developer
Alibaba Cloud Developer
Oct 10, 2024 · Databases

Inside MySQL 8.0: How Table, Page, and Row Locks Manage Concurrency

This article provides a comprehensive overview of MySQL 8.0's concurrency control mechanisms, detailing table‑level MDL locks, server‑ and engine‑layer table locks, page‑level B+Tree locking, and row‑level lock types with code examples and real‑world deadlock scenarios.

Concurrency ControlDatabase InternalsInnoDB
0 likes · 28 min read
Inside MySQL 8.0: How Table, Page, and Row Locks Manage Concurrency
Aikesheng Open Source Community
Aikesheng Open Source Community
Jun 26, 2024 · Databases

Slow Locking Logic in MySQL InnoDB

This article explains the slow‑path row‑locking algorithm used by InnoDB in MySQL 8.0.32, detailing how the engine checks whether a transaction already holds a lock, determines if it must wait, reuses existing lock structures, and allocates new ones when necessary.

Concurrency ControlDatabase InternalsInnoDB
0 likes · 15 min read
Slow Locking Logic in MySQL InnoDB
Aikesheng Open Source Community
Aikesheng Open Source Community
Jun 5, 2024 · Databases

Understanding the InnoDB Lock Module Structure

This article explains the structure and components of InnoDB's lock module, including the global lock_sys object, its hash tables, latch mechanisms, waiting thread slots, and related attributes, with detailed code examples and diagrams to illustrate how row and table locks are managed.

Database InternalsInnoDBconcurrency
0 likes · 15 min read
Understanding the InnoDB Lock Module Structure
Aikesheng Open Source Community
Aikesheng Open Source Community
May 29, 2024 · Databases

Analysis of InnoDB Table and Row Lock Structures in MySQL 8.0.32

This article examines the shared and distinct fields of InnoDB's table‑lock and row‑lock structures in MySQL 8.0.32, explains the layout of the lock_t, lock_table_t and lock_rec_t structs, decodes the type_mode bit‑field, and discusses how InnoDB merges compatible row‑locks using a bitmap memory area.

Database InternalsInnoDBconcurrency
0 likes · 13 min read
Analysis of InnoDB Table and Row Lock Structures in MySQL 8.0.32
JD Cloud Developers
JD Cloud Developers
Nov 14, 2023 · Databases

How MySQL Executes a Simple SQL Query: Step‑by‑Step Deep Dive

This article walks through the complete lifecycle of a MySQL query—from the client request, through connection handling, parsing, optimization, execution, and storage engine processing—illustrating each component with diagrams, code snippets, and a detailed analysis of execution order for both simple and join queries.

Database InternalsSQL Executionmysql
0 likes · 12 min read
How MySQL Executes a Simple SQL Query: Step‑by‑Step Deep Dive
Aikesheng Open Source Community
Aikesheng Open Source Community
Jun 6, 2023 · Databases

Why Does Inserting a Record that Triggers a Unique Index Conflict Add a Next‑Key Exclusive Lock on the Primary‑Key Supremum Record?

This article reproduces a MySQL 8.0.32 InnoDB scenario where inserting a row that violates a unique index causes a next‑key exclusive lock on the primary‑key supremum record, explains the underlying implicit‑lock mechanism, walks through the relevant source‑code stack, and details the lock‑conversion and rollback steps under REPEATABLE‑READ isolation.

Database InternalsInnoDBRepeatable Read
0 likes · 25 min read
Why Does Inserting a Record that Triggers a Unique Index Conflict Add a Next‑Key Exclusive Lock on the Primary‑Key Supremum Record?
MaGe Linux Operations
MaGe Linux Operations
May 20, 2023 · Databases

What Happens When MySQL Auto‑Increment IDs Reach Their Limits?

This article explains how MySQL handles auto‑increment primary keys, InnoDB’s internal row_id, transaction Xid and trx_id counters when they reach their maximum values, the resulting primary‑key conflicts, data overwrites, and a theoretical dirty‑read bug caused by counter wrap‑around.

Database InternalsInnoDBauto_increment
0 likes · 13 min read
What Happens When MySQL Auto‑Increment IDs Reach Their Limits?
ITPUB
ITPUB
Apr 30, 2023 · Databases

Inside Redis: Unveiling Its Core Architecture and Data Storage Mechanics

This article provides a detailed walkthrough of Redis's internal architecture, covering the client module, event‑driven networking, command processing, memory management, persistence strategies, high‑availability features, and the low‑level data structures such as redisServer, redisDb, dict, dictEntry, and redisObject that power its fast key‑value storage.

C languageData StructuresDatabase Internals
0 likes · 12 min read
Inside Redis: Unveiling Its Core Architecture and Data Storage Mechanics
ITPUB
ITPUB
Nov 13, 2022 · Databases

Inside MySQL: How the Server Handles Connections, Parsing, and Storage Engines

This article explains MySQL's client‑server architecture and walks through the three main stages—connection handling, query parsing and optimization, and storage engine selection—detailing protocols, authentication, cache behavior, optimizer mechanics, and engine characteristics with practical commands and examples.

Connection HandlingDatabase InternalsStorage Engine
0 likes · 21 min read
Inside MySQL: How the Server Handles Connections, Parsing, and Storage Engines
Top Architect
Top Architect
Jun 14, 2022 · Databases

Understanding MySQL Execution Process: Connectors, Cache, Parser, Optimizer, and Executor

This article explains MySQL's internal execution process—including the connector, cache, parser, optimizer, and executor—describes privilege tables and verification, discusses query caching removal, outlines logical SQL execution order, and provides practical tips for ordering WHERE conditions to improve performance.

Database InternalsQuery Optimizerdatabase
0 likes · 12 min read
Understanding MySQL Execution Process: Connectors, Cache, Parser, Optimizer, and Executor
High Availability Architecture
High Availability Architecture
Feb 23, 2022 · Databases

Redis Master‑Slave Replication Memory Consumption and the Shared Replication Buffer Design

This article analyzes the excessive memory usage and blocking issues in Redis master‑slave replication, explains how the upcoming Redis 7.0 shared replication buffer solves these problems, and details the design, implementation, and key considerations of the shared buffer mechanism.

Database InternalsMemory OptimizationReplication
0 likes · 14 min read
Redis Master‑Slave Replication Memory Consumption and the Shared Replication Buffer Design
IT Architects Alliance
IT Architects Alliance
Jan 21, 2022 · Databases

How Redis Overcame Single‑Thread Limits with Lazy Free and Multithreaded I/O

This article explains Redis’s original single‑threaded event‑driven architecture, its performance bottlenecks, and how versions 4.0 and 6.0 introduced Lazy Free and multithreaded I/O mechanisms—including asynchronous key deletion, background freeing, and I/O thread pools—to improve scalability while outlining their implementation details, limitations, and comparisons with Tair.

Database InternalsLazy FreeMultithreaded I/O
0 likes · 15 min read
How Redis Overcame Single‑Thread Limits with Lazy Free and Multithreaded I/O
政采云技术
政采云技术
Jan 20, 2022 · Databases

InnoDB MVCC: Concepts, Implementation, and Visibility Rules

This article explains InnoDB's Multi-Version Concurrency Control (MVCC) mechanism, detailing undo log, readview, hidden columns, visibility algorithms for RR and RC isolation levels, and includes source code snippets illustrating read view assignment and visibility checks.

Database InternalsInnoDBIsolation Levels
0 likes · 12 min read
InnoDB MVCC: Concepts, Implementation, and Visibility Rules
Architect's Journey
Architect's Journey
Aug 26, 2021 · Databases

Peeling Back MySQL InnoDB: A Deep Dive into Its Storage Engine

This article dissects MySQL's InnoDB storage engine by first exposing the internal page layout, then explaining the clustered index organization, and finally detailing the slot mechanism used for intra‑page queries, while illustrating insertion strategies and space‑reclamation techniques.

Clustered IndexDatabase InternalsInnoDB
0 likes · 11 min read
Peeling Back MySQL InnoDB: A Deep Dive into Its Storage Engine
Qunar Tech Salon
Qunar Tech Salon
Aug 3, 2021 · Databases

Deep Dive into MySQL 8.0 Server Architecture, Parser, and Optimizer

This article analyzes MySQL 8.0.25 source code, detailing the server architecture, parser reconstruction, prepare/rewrite stages, the optimizer transformations, and the new hypergraph optimizer, while also comparing these mechanisms with PostgreSQL’s processing pipeline.

Database InternalsHypergraphParser
0 likes · 12 min read
Deep Dive into MySQL 8.0 Server Architecture, Parser, and Optimizer
dbaplus Community
dbaplus Community
Jun 19, 2021 · Databases

Why Does MySQL’s KILL Command Sometimes Hang? A Deep Dive into Thread States and Kill Workflow

This article examines why MySQL’s KILL command often leaves a connection in a prolonged “Killed” state, analyzes the 5.7 source‑code flow, explains socket closure, thread flag handling, condition‑variable notifications, and reproduces real‑world cases that illustrate the underlying causes.

Database InternalsKill Commanddebugging
0 likes · 24 min read
Why Does MySQL’s KILL Command Sometimes Hang? A Deep Dive into Thread States and Kill Workflow
Big Data Technology & Architecture
Big Data Technology & Architecture
Feb 28, 2021 · Databases

Understanding the SQL Execution Process in ClickHouse

This article explains in detail how ClickHouse processes a user‑submitted SQL query, covering the server’s request handling, parsing, query rewrite, optimization, interpreter execution, and result transmission, while illustrating key source code snippets and architectural components.

BackendDatabase InternalsParser
0 likes · 18 min read
Understanding the SQL Execution Process in ClickHouse
Tencent Cloud Developer
Tencent Cloud Developer
Jan 14, 2021 · Databases

PostgreSQL Master-Slave Replication Performance Optimization: Solving Drop Table Bottleneck

The article explains how massive DROP TABLE operations in PostgreSQL master‑slave replication trigger costly buffer‑invalidation loops that cause severe lag, and describes extracting this step into a separate subprocess with a shared hash table, cutting replication lag from over 400 GB to about 10 MB—a 30,000‑fold speedup.

Database InternalsDatabase ReplicationWAL Logging
0 likes · 7 min read
PostgreSQL Master-Slave Replication Performance Optimization: Solving Drop Table Bottleneck
Su San Talks Tech
Su San Talks Tech
Dec 24, 2020 · Databases

Master MySQL: Deep Dive into Execution Flow, Logs, Indexes, Transactions, and Optimization

This comprehensive guide explains MySQL's server and storage engine layers, SQL execution order, BinLog/RedoLog/UndoLog mechanisms, index structures and design principles, transaction isolation levels, lock types, MVCC, buffer pool behavior, table slimming, join strategies, statistics, random queries, and practical optimization techniques for high‑performance database operations.

Database Internalsindexesmysql
0 likes · 43 min read
Master MySQL: Deep Dive into Execution Flow, Logs, Indexes, Transactions, and Optimization
Tencent Cloud Developer
Tencent Cloud Developer
Dec 10, 2020 · Databases

Understanding LevelDB Architecture, Read/Write Flow, and Compaction Process

LevelDB stores data using an in‑memory Memtable that flushes to immutable tables and disk‑based SSTables, writes are logged then batched and applied through a writer queue, reads check Memtable, immutable Memtable, then SSTables, and background compactions merge tables to improve read performance and reclaim space.

Database InternalsLSM‑TreeLevelDB
0 likes · 16 min read
Understanding LevelDB Architecture, Read/Write Flow, and Compaction Process
ITPUB
ITPUB
Nov 23, 2020 · Databases

Eliminating InnoDB Adaptive Hash Index Lock Contention for Faster Queries

The article examines the hidden lock‑contention issue in InnoDB’s Adaptive Hash Index (AHI) observed during high‑concurrency sysbench runs, explains why multiple threads block on the AHI hash table’s exclusive lock, and presents a lightweight fallback optimization that checks the lock before building AHI, reducing lock wait time and stabilizing QPS performance.

Adaptive Hash IndexDatabase InternalsInnoDB
0 likes · 9 min read
Eliminating InnoDB Adaptive Hash Index Lock Contention for Faster Queries
Full-Stack Internet Architecture
Full-Stack Internet Architecture
Oct 26, 2020 · Databases

Understanding MySQL Binlog, Undo Log, Redo Log, and Change Buffer

This article provides a comprehensive overview of MySQL’s logging mechanisms—including Binlog, Undo log, Redo log, and Change Buffer—explaining their concepts, roles in replication and crash‑recovery, recording formats, flush timing, two‑phase commit, checkpoint handling, and how they interact during data modifications.

BinlogChange BufferDatabase Internals
0 likes · 22 min read
Understanding MySQL Binlog, Undo Log, Redo Log, and Change Buffer
Xueersi Online School Tech Team
Xueersi Online School Tech Team
Oct 16, 2020 · Databases

Deep Dive into MySQL InnoDB Record Lookup and Deletion Process

This article explains how MySQL InnoDB locates and deletes a specific row by describing the buffer‑pool lookup, B‑tree page traversal, page‑directory binary search, linear record scan, the compact physical record format, and the handling of signed integers and next‑record offsets, with GDB debugging examples.

Compact Row FormatDatabase InternalsDeletion
0 likes · 25 min read
Deep Dive into MySQL InnoDB Record Lookup and Deletion Process
JavaEdge
JavaEdge
Jul 4, 2020 · Databases

How MySQL Executes a Query: From Connection to Execution Engine

This article explains MySQL’s internal workflow, covering the Server layer components, Storage Engine layer, connection handling, query cache behavior, lexical and syntax parsing, optimization decisions, and execution steps, including tips for long‑connection management and common pitfalls.

Connection ManagementDatabase InternalsQuery Execution
0 likes · 9 min read
How MySQL Executes a Query: From Connection to Execution Engine
dbaplus Community
dbaplus Community
Mar 19, 2020 · Databases

Inside Redis: A Deep Dive into Its Core Data Structures

This article explains the internal implementations of Redis’s five major data structures—simple dynamic strings (SDS), linked lists, dictionaries, skiplists, integer sets, and ziplists—detailing their definitions, memory layouts, key characteristics, and how Redis leverages them for high‑performance storage and retrieval.

Data StructuresDatabase InternalsSDS
0 likes · 12 min read
Inside Redis: A Deep Dive into Its Core Data Structures
Qunar Tech Salon
Qunar Tech Salon
Feb 14, 2020 · Databases

Understanding InnoDB Rollback and UNDO Log Architecture in MySQL

This article explains the internal structure of InnoDB rollback segments, UNDO log storage formats, and the recovery process in MySQL, detailing how transaction IDs, segment headers, page headers, and log records are organized and used to safely roll back or purge data.

Database InternalsInnoDBmysql
0 likes · 22 min read
Understanding InnoDB Rollback and UNDO Log Architecture in MySQL
Qunar Tech Salon
Qunar Tech Salon
Feb 10, 2020 · Databases

InnoDB Buffer Pool Management Mechanism and Implementation Details

This article explains the theory behind InnoDB's log management, details the architecture and dynamic sizing of the Buffer Pool, describes its internal data structures and multi‑instance implementation, and provides annotated source code snippets to illustrate how MySQL allocates and manages buffer pages.

Database InternalsInnoDBbuffer pool
0 likes · 15 min read
InnoDB Buffer Pool Management Mechanism and Implementation Details
Aikesheng Open Source Community
Aikesheng Open Source Community
Dec 30, 2019 · Databases

Understanding MySQL Full‑Table‑Scan Data Access and Field Filtering Process

This article explains how MySQL processes a full‑table‑scan query, detailing the construction of read‑sets, template creation, cursor positioning, row conversion to MySQL format, where‑clause filtering, and subsequent row iteration, while highlighting the performance impact of the number of selected fields.

Database InternalsFull Table ScanRead Set
0 likes · 11 min read
Understanding MySQL Full‑Table‑Scan Data Access and Field Filtering Process
Aikesheng Open Source Community
Aikesheng Open Source Community
Dec 3, 2019 · Databases

Understanding How MySQL SHOW PROCESSLIST Calculates the Time Column and Why Negative Values Appear

This article explains the internal calculation of the Time column shown by MySQL's SHOW PROCESSLIST command, covering the source functions, overloads of THD::set_time, various scenarios that affect the result—including replication lag, manual timestamp settings, and idle sessions—and why Percona and official builds may display different values.

Database InternalsReplicationSHOW PROCESSLIST
0 likes · 10 min read
Understanding How MySQL SHOW PROCESSLIST Calculates the Time Column and Why Negative Values Appear
Tencent Database Technology
Tencent Database Technology
Nov 28, 2019 · Databases

InnoDB Buffer Pool Architecture, Data Structures, and Page Lifecycle

This article provides a comprehensive overview of InnoDB's buffer pool, detailing its role as a data cache, the underlying data structures such as instances, chunks, and blocks, the page lifecycle from allocation to flushing, and discusses limitations of the default page‑cleaner implementation along with Percona's enhancements.

Database InternalsInnoDBPage lifecycle
0 likes · 16 min read
InnoDB Buffer Pool Architecture, Data Structures, and Page Lifecycle
Aikesheng Open Source Community
Aikesheng Open Source Community
Nov 14, 2019 · Databases

Understanding InnoDB Tablespace Space Management

This article explains how InnoDB stores user tables and indexes in .ibd files, describes the structure of tablespaces, pages, extents, header pages, XDES entries, INODE pages, and file segments, and shows how indexes allocate and free these internal structures as they grow and shrink.

Database InternalsInnoDBPages
0 likes · 10 min read
Understanding InnoDB Tablespace Space Management
Aikesheng Open Source Community
Aikesheng Open Source Community
Sep 2, 2019 · Databases

Understanding MySQL Write‑Set Based Parallel Replication and Last‑Commit Handling

This article explains MySQL's write‑set based parallel replication, detailing how writeset hashes are generated, stored in a historical map, and used to adjust the last‑commit value for improved parallel replay, including configuration parameters, code examples, and the impact of different dependency‑tracking modes.

BinlogDatabase InternalsTransaction Dependency
0 likes · 15 min read
Understanding MySQL Write‑Set Based Parallel Replication and Last‑Commit Handling
Tencent Cloud Developer
Tencent Cloud Developer
Jun 3, 2019 · Databases

Storage Engine Overview and InnoDB Feature Design

An InnoDB storage engine sits above the file system and below SQL tools, providing transactions with redo/undo logs, row and table locking, MVCC, B+‑tree and adaptive hash indexes, compression, encryption, checkpointing, multi‑threaded buffering, backup and replication mechanisms, and extensive performance‑monitoring commands.

Database InternalsInnoDBPerformance Monitoring
0 likes · 11 min read
Storage Engine Overview and InnoDB Feature Design
DataFunTalk
DataFunTalk
Apr 22, 2019 · Databases

Deep Dive into TiDB SQL Optimizer and Execution Engine

This article provides a comprehensive technical overview of TiDB's architecture, its SQL optimizer—including logical and physical optimization phases, rule‑based transformations, join ordering, and statistics collection—and outlines future work to improve query planning stability and performance.

Database InternalsQuery PlanningSQL Optimizer
0 likes · 16 min read
Deep Dive into TiDB SQL Optimizer and Execution Engine
Efficient Ops
Efficient Ops
Aug 22, 2018 · Databases

Unlocking MySQL: Deep Dive into Metadata and InnoDB Lock Mechanisms

This article presents a comprehensive walkthrough of MySQL's two‑layer architecture, metadata (MDL) locks, InnoDB lock types—including gap and record locks—and practical debugging techniques, helping readers understand lock acquisition, release points, and source‑code entry points for effective database operation and development.

Database InternalsInnoDBLock Mechanisms
0 likes · 19 min read
Unlocking MySQL: Deep Dive into Metadata and InnoDB Lock Mechanisms
dbaplus Community
dbaplus Community
Sep 7, 2017 · Databases

Why MySQL 5.7 Partition Tables Slow Down Updates: Uncovering an InnoDB Lock Regression

This article explains how upgrading to MySQL 5.7.18 caused severe performance drops on partitioned tables due to a regression that locks too many rows during single‑row updates, details the reproduction steps, shows the InnoDB lock inspection, pinpoints the faulty code path, and confirms the bug with further tests.

Database InternalsInnoDBLock Regression
0 likes · 9 min read
Why MySQL 5.7 Partition Tables Slow Down Updates: Uncovering an InnoDB Lock Regression
ITPUB
ITPUB
Jun 23, 2017 · Databases

Inside MySQL InnoDB Buffer Pool: Architecture, Data Structures, and Optimization

This article provides an in‑depth technical walkthrough of MySQL InnoDB's Buffer Pool, covering its core data structures, instance layout, LRU and Flush list management, memory allocation strategies, read‑ahead/write‑ahead mechanisms, double‑write buffering, and the specialized threads that keep the pool efficient.

Database InternalsInnoDBLRU
0 likes · 39 min read
Inside MySQL InnoDB Buffer Pool: Architecture, Data Structures, and Optimization
ITPUB
ITPUB
Nov 7, 2016 · Databases

Inside MySQL’s MEM_ROOT: How Memory Allocation Really Works

This article provides an in‑depth technical walkthrough of MySQL’s MEM_ROOT memory allocator, covering the key macros, the MEM_ROOT and USED_MEM structures, initialization and allocation routines, pointer‑manipulation logic, and the heuristic algorithm that grows block sizes as usage increases.

Database InternalsMEM_ROOTc++
0 likes · 8 min read
Inside MySQL’s MEM_ROOT: How Memory Allocation Really Works
ITPUB
ITPUB
Sep 5, 2016 · Databases

Understanding Oracle Enqueue Locks, Resource Structures, and Hash Tables

This article explains how Oracle protects shared resources with enqueue queues, details the naming of TM queue locks per table, describes the resource structure (KSQRS) that tracks owners, waiters and converters, and shows how hash tables and related parameters manage these structures efficiently.

Database InternalsEnqueueLocks
0 likes · 11 min read
Understanding Oracle Enqueue Locks, Resource Structures, and Hash Tables
ITPUB
ITPUB
Aug 17, 2016 · Databases

Decoding Oracle Enqueue Locks: Queues, Resource Structures, and Hash Buckets

This article explains how Oracle protects shared resources using enqueue queues, details the naming of queue identifiers like TM, describes the creation and composition of resource structures in the SGA, and examines the hash‑bucket mechanism that locates these structures while highlighting relevant parameters and diagnostic queries.

Database InternalsEnqueue LocksOracle
0 likes · 13 min read
Decoding Oracle Enqueue Locks: Queues, Resource Structures, and Hash Buckets
ITPUB
ITPUB
Jun 23, 2016 · Databases

How to Uncover Oracle Hidden Parameters with Views and Trace

This article explains two practical techniques for identifying Oracle hidden parameters—querying internal views like GV$PARAMETER and X$ tables, and using AUTOTRACE to inspect execution plans—so DBAs can reveal undocumented settings, their defaults, and current values.

Database InternalsHidden ParametersOracle
0 likes · 5 min read
How to Uncover Oracle Hidden Parameters with Views and Trace
Architect
Architect
Jun 22, 2016 · Databases

Introduction to InnoDB Row Locks, Splitting, Inheritance, and Migration

This article explains InnoDB row lock types, including shared and exclusive locks and GAP variants, describes how locks split, inherit, and migrate during B‑tree operations, provides code examples and SQL demonstrations, and discusses related bugs and lock compatibility.

Database InternalsInnoDBLock Splitting
0 likes · 8 min read
Introduction to InnoDB Row Locks, Splitting, Inheritance, and Migration
ITPUB
ITPUB
May 31, 2016 · Databases

Inside PostgreSQL: How SQL Queries Are Processed from Start to Finish

This article walks through PostgreSQL's complete SQL execution pipeline, detailing each component—from the Main entry point and Postmaster process to parsing, traffic coordination, query rewriting, plan generation, and execution—while comparing its process architecture to other database systems.

Database InternalsPostmasterQuery Planner
0 likes · 6 min read
Inside PostgreSQL: How SQL Queries Are Processed from Start to Finish
21CTO
21CTO
Apr 1, 2016 · Databases

How MySQL 5.7 Optimizes Metadata Locks and Hash Scan for Faster Replication

This article details the evolution of MySQL's Metadata Lock subsystem, the implementation of lock‑free hash tables and fast‑path locking in MySQL 5.7, the hash_scan algorithm used in replication, as well as performance enhancements in TokuDB 7.5.0 and MariaDB's small‑LIMIT filesort optimization.

Database InternalsHash Scanmetadata lock
0 likes · 18 min read
How MySQL 5.7 Optimizes Metadata Locks and Hash Scan for Faster Replication
21CTO
21CTO
Mar 2, 2016 · Databases

Inside MySQL InnoDB Full-Text Index: Architecture, Operations, and Optimization

This article examines MySQL’s InnoDB full‑text indexing from MySQL 5.6 onward, detailing supported search modes, the structure of auxiliary index files, the lifecycle of DML operations, transaction handling, cache synchronization, optimization procedures, background threads, monitoring tables, stop‑word configuration, and the built‑in n‑gram parser.

Database InternalsFull‑Text SearchInnoDB
0 likes · 23 min read
Inside MySQL InnoDB Full-Text Index: Architecture, Operations, and Optimization
Architect
Architect
Mar 1, 2016 · Databases

In-depth Overview of MySQL InnoDB Page Types, Compression, IO Subsystem, and Buffer Pool Management

This article provides a comprehensive technical overview of MySQL InnoDB's internal page structures—including compressed, system, external, encrypted, and R‑TREE pages—along with detailed explanations of the IO subsystem, double‑write buffer, temporary tablespaces, and buffer pool memory management mechanisms.

Database InternalsIO SubsystemInnoDB
0 likes · 25 min read
In-depth Overview of MySQL InnoDB Page Types, Compression, IO Subsystem, and Buffer Pool Management
Architect
Architect
Feb 6, 2016 · Databases

Introduction to InnoDB Transaction Lock System

This article provides a comprehensive overview of InnoDB's transaction lock mechanisms, covering row‑level lock types, table‑level locks, lock management procedures, deadlock detection, and practical examples, all based on MySQL 5.7.10.

Database InternalsInnoDBTransaction Locks
0 likes · 30 min read
Introduction to InnoDB Transaction Lock System
dbaplus Community
dbaplus Community
Nov 19, 2015 · Databases

Understanding Oracle Undo and Redo: Deep Dive into Transaction Mechanics

This article explains the internal structures and roles of Oracle undo and redo logs in transaction processing, walks through practical experiments that dissect undo segment headers, undo blocks, undo chains, redo records, fast‑commit behavior, and the true nature of DELETE operations, and shows how these insights help diagnose ORA‑600 startup failures.

Database InternalsOracleRedo
0 likes · 14 min read
Understanding Oracle Undo and Redo: Deep Dive into Transaction Mechanics