Tagged articles

memory fragmentation

19 articles · Page 1 of 1

Sep 18, 2026 · Backend Development

Hidden GC Pauses Causing Random API Timeouts: JVM STW Troubleshooting Guide

This article reveals how long GC stop-the-world pauses cause random API timeouts without errors, detailing two fault scenarios, a four-step GC log analysis SOP with specific JVM flags, four root causes including young generation sizing and memory fragmentation, and optimization strategies from emergency restarts to G1/ZGC upgrades with monitoring alerts.

Full GCG1GC

0 likes · 15 min read

Hidden GC Pauses Causing Random API Timeouts: JVM STW Troubleshooting Guide

Deepin Linux

Aug 15, 2026 · Fundamentals

Analyzing New Heap Allocation Overhead in Linux Virtual Address Space

This article explains Linux process virtual address spaces, details the multi‑step internals of the C++ new operator, and analyzes its memory‑fragmentation, time, and space overheads through code examples and benchmarks, then offers practical mitigation techniques such as memory pools and smart pointers.

C++LinuxVirtual Memory

0 likes · 26 min read

Analyzing New Heap Allocation Overhead in Linux Virtual Address Space

Deepin Linux

May 13, 2026 · Fundamentals

Don’t Claim Linux Memory‑Tuning Skills Without Mastering Memory Compaction

This article explains Linux memory compaction—from its core principles and page‑migration mechanics to the different compaction strategies, trigger conditions, practical test cases, and optimization tips—showing how proper compaction resolves fragmentation, improves allocation success, and boosts overall system performance.

LinuxMemory CompactionPage Migration

0 likes · 47 min read

Don’t Claim Linux Memory‑Tuning Skills Without Mastering Memory Compaction

Deepin Linux

May 11, 2026 · Fundamentals

Eliminate Memory Fragmentation: Understanding Memory Pools

The article explains how frequent dynamic allocations cause external and internal memory fragmentation, illustrates the problem with C++ examples, and shows that pre‑allocating a large contiguous block as a memory pool—managed via block division, free‑list tracking, and thread‑safe operations—significantly reduces fragmentation, improves allocation speed, and boosts concurrency performance.

C++Low-Level ProgrammingPerformance Optimization

0 likes · 30 min read

Eliminate Memory Fragmentation: Understanding Memory Pools

MaGe Linux Operations

Dec 26, 2025 · Operations

Taming vLLM OOM: Real‑World Causes and Proven Fixes for Production

This article examines why vLLM experiences out‑of‑memory errors in production, explains memory fragmentation caused by PagedAttention, outlines four typical OOM scenarios with concrete command‑line solutions, and provides deep analysis, configuration scripts, dynamic tuning, troubleshooting flowcharts, monitoring alerts, and best‑practice recommendations.

GPUOOMPython

0 likes · 24 min read

Taming vLLM OOM: Real‑World Causes and Proven Fixes for Production

Deepin Linux

Jun 30, 2025 · Fundamentals

Boost C++ Performance with Fixed-Size Memory Pools: Theory and Code

This article explains why frequent dynamic memory allocation can cause slowdown and fragmentation, introduces fixed-size memory pools as an efficient solution, details their core principles, data structures, key allocation and deallocation functions, and demonstrates their performance advantage with C++ code examples and benchmarks.

C++custom allocatorfixed-size allocation

0 likes · 20 min read

Boost C++ Performance with Fixed-Size Memory Pools: Theory and Code

Liangxu Linux

Jun 25, 2025 · Fundamentals

Why malloc/free Struggle in High‑Concurrency: Inside ptmalloc’s Architecture

This article examines the internal design of glibc’s ptmalloc, explains how malloc_state, malloc_chunk, fastbins, bins and the top chunk work, analyzes lock contention and memory fragmentation in multithreaded scenarios, and presents a C benchmark that measures these performance issues.

C++freemalloc

0 likes · 12 min read

Why malloc/free Struggle in High‑Concurrency: Inside ptmalloc’s Architecture

Deepin Linux

Jun 6, 2025 · Fundamentals

How eBPF Can Tackle Linux Memory Fragmentation and Boost Android Performance

This article explains the problem of internal and external memory fragmentation in Linux systems, introduces eBPF as a powerful tracing tool, and provides step‑by‑step guidance for building, loading, and running eBPF programs to analyze and mitigate fragmentation on both Linux and Android platforms.

AndroidBPFLinux kernel

0 likes · 22 min read

How eBPF Can Tackle Linux Memory Fragmentation and Boost Android Performance

Sanyou's Java Diary

Mar 27, 2025 · Databases

Why Your MySQL Indexes Fail: Cost Estimation, Fragmentation, and Slow Query Secrets

This article examines MySQL slow‑query troubleshooting, explaining how the optimizer estimates costs, why indexes may be ineffective even when present, the impact of memory fragmentation, pitfalls of prefix indexes, index merging techniques, and additional resource‑related factors that can cause seemingly healthy SQL statements to become slow.

Index OptimizationMySQLcost estimation

0 likes · 11 min read

Why Your MySQL Indexes Fail: Cost Estimation, Fragmentation, and Slow Query Secrets

Liangxu Linux

Jul 20, 2024 · Fundamentals

How Does malloc Actually Allocate Memory? A Visual Guide to Heap Management

This article explains what happens inside a computer when you request memory with malloc, covering the role of the standard library, the compilation and linking process, memory layout, heap allocation, fragmentation, and how the operating system expands the heap.

C ProgrammingHeapmalloc

0 likes · 6 min read

How Does malloc Actually Allocate Memory? A Visual Guide to Heap Management

Java Tech Enthusiast

Jun 29, 2024 · Fundamentals

Understanding Memory Allocation in C

The article explains C’s memory allocation, detailing how functions like malloc obtain heap space, the role of system calls such as brk, the distinction between stack and heap, address layout, fragmentation challenges, and practical implications for efficient dynamic memory management.

C ProgrammingHeapmalloc

0 likes · 5 min read

OPPO Kernel Craftsman

Nov 10, 2023 · Operations

Memory Compaction in the Linux Kernel: Mechanisms, Strategies, and Implementation Details

Linux’s memory compaction mitigates external fragmentation by moving movable pages, employing four strategies—direct, passive (kcompactd), proactive, and active—each invoking the compact_zone core with configurable compact_control parameters, migrate‑page and free‑page scanners, and distinct trigger and exit conditions.

Linux kernelMemory CompactionPage Migration

0 likes · 45 min read

Memory Compaction in the Linux Kernel: Mechanisms, Strategies, and Implementation Details

ByteDance SYS Tech

May 19, 2023 · Backend Development

Why DPDK Memory Allocation Slows Down and How to Fix It

This article investigates the performance degradation caused by DPDK memory fragmentation, explains the underlying heap and element management, presents detailed profiling and test results, and proposes two practical solutions that dramatically reduce allocation latency and improve overall system throughput.

C++DPDKmalloc

0 likes · 16 min read

Why DPDK Memory Allocation Slows Down and How to Fix It

Liangxu Linux

Apr 6, 2023 · Operations

How Linux Compacts Memory to Eliminate Fragmentation

This article explains the problem of memory fragmentation in Linux, describes the compaction algorithm that moves free pages together, and walks through the key kernel functions—alloc_pages_node, __alloc_pages_direct_compact, try_to_compact_pages, isolate_migratepages, migrate_pages, and unmap_and_move—detailing their roles in gathering movable pages and relocating them to create contiguous memory blocks.

Linuxalloc_pageskernel

0 likes · 10 min read

How Linux Compacts Memory to Eliminate Fragmentation

Sohu Tech Products

Sep 14, 2022 · Databases

Understanding Redis Memory Fragmentation and How to Manage It

This article explains why Redis may show high OS‑allocated memory despite low data usage, describes the causes of memory fragmentation, and provides practical steps—including configuration changes and automatic defragmentation settings—to diagnose and mitigate fragmentation for stable performance.

Cachingdatabasesmemory fragmentation

0 likes · 9 min read

Understanding Redis Memory Fragmentation and How to Manage It

Aikesheng Open Source Community

Apr 25, 2022 · Databases

Diagnosing Periodic Redis Latency Caused by BGSAVE and Fork Overhead

The article analyzes a recurring one‑second pause in a Redis 4.0 master‑slave setup, identifies the periodic BGSAVE fork operation as the root cause through metrics like latest_fork_usec, and presents mitigation strategies such as memory limits, activedefrag, and migration to a lower‑RSS instance.

BGSAVEPerformancefork

0 likes · 6 min read

Diagnosing Periodic Redis Latency Caused by BGSAVE and Fork Overhead

Aikesheng Open Source Community

Mar 29, 2021 · Databases

Understanding Low Redis Memory Fragmentation Ratio and Its Real Causes

This article explains why a low Redis memory fragmentation ratio is not necessarily caused by swap usage, demonstrates experiments with disabled swap and varying repl‑backlog‑size, and concludes that large replication buffers and small data sets can naturally produce ratios far below 1, which is normal.

BacklogRedisReplication

0 likes · 7 min read

Understanding Low Redis Memory Fragmentation Ratio and Its Real Causes

Code Ape Tech Column

Dec 6, 2020 · Databases

Why Redis Memory Remains High After Deleting Keys and How to Fix Fragmentation

This article explains why Redis memory usage stays high after deleting keys, describes memory fragmentation causes, shows how to detect fragmentation with INFO memory and mem_fragmentation_ratio, and provides practical steps and configuration options to clean and prevent fragmentation.

Active DefragmentationINFO commandRedis

0 likes · 10 min read

Why Redis Memory Remains High After Deleting Keys and How to Fix Fragmentation

Baidu Intelligent Testing

Jun 14, 2016 · Fundamentals

Analysis of Common C/C++ Memory Issues: Leaks and Performance Degradation

This article examines typical C/C++ memory problems, classifying them into memory leaks and performance issues caused by fragmentation, explains root causes such as lost pointers, improper releases, unbounded allocations, and provides diagnostic examples and mitigation strategies using memory pools like tcmalloc.

C++PerformanceTCMalloc

0 likes · 13 min read

Analysis of Common C/C++ Memory Issues: Leaks and Performance Degradation