1 views collected around this technical thread.
This article explains Linux I/O scheduler concepts, compares the main algorithms (noop, cfq, deadline), shows how to view and modify scheduler settings on CentOS 6/7, and presents performance test results indicating the optimal scheduler choices for SSD and SAS disks.
This guide explains how Ceph cache pools work, compares read‑only and write‑back cache types, and provides step‑by‑step commands for creating, configuring, and safely removing cache pools, including CRUSH rule adjustments to ensure data lands on SSDs.
The article examines how different I/O patterns, such as sequential writes, request size interference, and read/write conflicts, affect NVMe SSD performance, explains the underlying mechanisms like write amplification and GC behavior, and proposes software-level optimizations—including large‑block writes, Optane caching, and OpenChannel/Object SSD designs—to improve throughput and latency.
The article analyzes how hardware components, software mechanisms, and environmental conditions collectively impact NVMe SSD performance, explaining why real‑world results often differ from vendor specifications and highlighting the roles of NAND type, controller architecture, PCIe bandwidth, garbage collection, temperature, and wear‑leveling.
The paper presents a tiered NVMe SSD solution for ad‑ranking retrieval, using zone‑aware hardware, Direct I/O with libaio/IoUring, and an adaptive pipeline scheduler to cut long‑tail read latency and boost throughput, enabling larger‑than‑memory signals and improving ranking accuracy and revenue.
This article explains the different server storage types—including mechanical HDDs, solid‑state SSDs, various interfaces, RAID arrays, and network‑attached storage—while covering their structures, performance characteristics, Linux device handling, and how to choose the right solution based on cost, capacity, speed, and reliability.
The article presents a large‑scale study of SSD failure prediction using SMART logs from multiple vendors, introduces the Wear‑Updated Integrated Feature Ranking (WEFR) method to automatically and robustly select predictive features, and demonstrates its effectiveness through extensive experiments on real‑world data.
The article explains CXL SSD technology, describing its memory‑consistent interconnect, the three device classes, the CXL.io, CXL.cache and CXL.memory protocols, its relationship to PCIe, enhancements in versions 2.0 and 3.0, and performance advantages demonstrated by Samsung and other vendors.
This article presents a large‑scale study of SSD failure prediction using SMART logs from Alibaba data centers, introduces the Wear‑Updated Integrated Feature Ranking (WEFR) method for robust feature selection across different drive models and wear levels, and demonstrates its effectiveness through extensive experiments.
This paper presents a FAST 2022 study of nearly two million SSDs from a major storage vendor, revealing key operational traits such as slow PE‑cycle consumption, variable write amplification, wear‑leveling inefficiencies, system fullness growth, and read‑dominant workloads in enterprise environments.
This article explains the fundamentals of Ceph cache tiering, covering cache and buffer concepts, the two cache‑pool modes (write‑back and read‑forward), step‑by‑step deployment, configuration parameters, and proper procedures for creating, tuning, and safely removing cache pools.
This article provides an in‑depth technical overview of the NVMe (Non‑Volatile Memory Express) protocol over PCIe, covering its logical device interface, namespace concepts, queue mechanisms, register layouts, command formats, controller initialization, interrupt handling, and data protection features.
This article describes how a ClickHouse cluster was re‑architected to use SSD for hot data and SATA HDD for cold data, details the configuration of custom storage policies, explains a restart‑time path‑collision error, and provides the fix to restore normal operation.
The report provides a comprehensive overview of enterprise‑grade SSD technology, covering NAND flash market share and advancements, DRAM role and growth, SSD production trends, emerging 3D/4D NAND technologies, and the competitive landscape of major storage manufacturers worldwide.
The article explains core flash storage techniques—including global load balancing, multi‑stream partitioning, and end‑to‑end I/O priority—by describing Active‑Active architectures, hash‑based request distribution, cache mirroring, data classification, and latency management to improve performance, reliability, and SSD lifespan.
The article explains the fully interconnected architecture of an all‑flash storage system, covering redundant FRU modules, RDMA‑based high‑speed networking, intelligent disk enclosures, SSD structure, wear‑leveling, bad‑block management, data redundancy, and the differences between SAS and NVMe protocols.
This article explains the fundamentals of SSDs, their hardware and firmware components, distinguishes consumer and enterprise grades, and compares major storage interfaces such as SATA, SAS, and PCIe/NVMe, highlighting performance, reliability, and emerging trends like PCIe 5.0 for data‑center deployments.
This guide demonstrates how to customize Ceph's CRUSH map to separate SSD and SATA OSDs into distinct buckets, create dedicated crush rules, compile and apply the new map, and verify that data is correctly placed on the appropriate storage devices.
This article examines how modern SSDs demand higher data rates and IOPS, compares the SATA, SAS, and PCIe storage interfaces, and discusses performance trade‑offs, compatibility considerations, and latency factors to help choose the most suitable interface for a given system.
The article explains how the new NVMe ZNS (Zoned Namespace) standard, likened to a 5G upgrade for storage, improves SSD performance and lifespan, outlines its technical background, and describes how major hardware vendors and cloud providers are adopting it for data‑center and future consumer storage solutions.