Author 晓兵 weixin: ssbandjl 公众号: 云原生云 简介 分布式异步对象存储 (DAOS) 是一种开源软件定义的对象存储，专为大规模分布式非易失性内存 (NVM) 而设计。DAOS 利用存储级内存 (SCM) 和 NVM express (NVMe) 等下一代 NVM 技术，同时呈现键值存储接口并提供事务性非阻塞 I/O、高级数据保护和自我修复等功能 商品硬件、端到端数据完整性、细粒度数据控……

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Author 晓兵 weixin: ssbandjl 公众号: 云原生云 Blobstore 编程指导 In this document @ref blob_pg_audience @ref blob_pg_intro @ref blob_pg_theory @ref blob_pg_design @ref blob_pg_examples @ref blob_pg_config @ref blob_pg_component Target Audience The programmer’s guide is intended for developers authoring applications that utilize the SPDK Blobstore. It is intended to supplement the source code in providing an overall understanding of how to integrate Blobstore into an application as well as provide some high level insight into how Blobstore works behind the scenes. It is not intended to serve as a design document or an API reference and in some cases source code snippets and high level sequences will be discussed; for the latest source code reference refer to the repo. 程序员指南适用于编写使用 SPDK Blobstore 的……

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Author 晓兵 weixin: ssbandjl 公众号: 云原生云 NVme over Fabrics: 也称为 NVMe-oF 和 non-volatile memory express over fabric，是一种协议规范，旨在使用 NVMe 协议通过网络结构将主机连接到存储。 该协议旨在通过网络在主机和目标固态存储设备或系统之间实现数据传输——通过基于 NVMe 消息的命令完成。 数据传输可以通过以太网、光纤通道 (FC) 或 InfiniBand 等方法传输 Target Audience This programming guide is intended……

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Author 晓兵 weixin: ssbandjl 公众号: 云原生云 Submitting I/O to an NVMe Device 提交I/O到NVME设备 The NVMe Specification 规范 The NVMe specification describes a hardware interface for interacting with storage devices. The specification includes network transport definitions for remote storage as well as a hardware register layout for local PCIe devices. What follows here is an overview of how an I/O is submitted to a local PCIe device through SPDK. NVMe 规范描述了用于与存储设备交互的硬件接口。 该规范包括远程存储的网络传输定义以及本地 PCIe 设备的硬件寄存器布局。……

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Author 晓兵 weixin: ssbandjl 公众号: 云原生云 A block layer cache (bcache) What is bcache? Bcache is a Linux kernel block layer cache. It allows one or more fast disk drives such as flash-based solid state drives (SSDs) to act as a cache for one or more slower hard disk drives. Hard drives are cheap and big, SSDs are fast but small and expensive. Wouldn’t it be nice if you could transparently get the advantages of both? With Bcache, you can have your cake and eat it too. Bcache patches for the Linux kernel allow one to use SSDs to cache other block devices. It’s analogous to L2Arc for ZFS, but Bcache also does writeback caching (besides just write through caching), and it’s filesystem agnostic. It’s designed to be switched on with a minimum……

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linux-aio 参考链接 linux-aio io_submit man aio POSIX linux aio 实现概览 Introduction 简介 1 注意与POSIX语义的aio - POSIX asynchronous I/O overview POSIX异步I/O接口, 有区别 Note, Linux AIO is now subsumed by the io_uring API (tutorial, LWN coverage). The below explanation is mostly useful for old kernels. 请注意，Linux AIO 现在包含在 io_uring API（教程，LWN 覆盖范围）中。 下面的解释对旧内核最有用。 The Asynchronous Input/Output (AIO) interface allows many I/O requests to be submitted in parallel without the overhead……

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