© XXX Page 1 of 11 CurveFS Client 概要设计（已实现）© XXX Page 2 of 11 背景 概述 关键接口分析 init destroy lookup write read open create & mknod mkdir forget unlink rmdir opendir readdir getattr & setattr access rename 作者 内容 2021-04-27 许超杰 初稿 背景 CurveFS初步设计见 ， 目前需细化Client端设计 CurveFS方案设计（总体设计，只实现了部分） 概述 CurveFS client 向上提供两层接口，分别是© XXX Page 3 of 11 对接fuse，提供通用文件系统接口。对于fuse接口，先前进行了一些调研，见FUSE调研 erblock），块分配器（bitmap）和root inode所在的copyset、 metaserver ip等信息 去metaserver获取文件系统信息（super block），缓存到client端。 destroy void (*destroy) (void *userdata); 清理init缓存的文件系统信息。 lookup void (*lookup) (fuse_req_t

TechAtBloomberg.com © 2024 Bloomberg Finance L.P. All rights reserved. • Create a basic HTTP server. • Allow a single-threaded server handling multiple clients. • Use the sender/receiver asynchronous an async_scope for outstanding work. • Initial work consist of accepting incoming client connections. • Each client processes requests until an error is received. Basic DesignTechAtBloomberg.com © std::execution (sender/receiver): http://wg21.link/p2300 • https://github.com/NVIDIA/stdexec.git • https://github.com/beman-project/execution26 • Sender/receiver networking: http://wg21.link/p2762 • Implementation:

URVE基本架构 01 02 03 04 Client总体介绍 热升级NEBD总体介绍 新版本Client/NEBD性能优化CURVE基本架构 • 元数据节点 MDS • 管理和存储元数据信息 • 感知集群状态，合理调度 • 数据节点 Chunkserver • 数据存储 • 副本一致性，raft • 客户端 Client • 对元数据增删改查 • 对数据增删改查 • • 快照克隆服务器CURVE基本架构 01 02 03 04 Client总体介绍 热升级NEBD总体介绍 新版本Client/NEBD性能优化 QEMU、Curve-NBD：上层应用  通过链接curve-client使用curve提供的服务  FileManager：提供接口，记录已挂载卷  FileInstance：对应一个已挂载的卷  LeaseExecuto 行通信  前者负责IO请求  后者负责获取复制组(copyset)的leader  MDSClient：负责与MDS交互，挂卸载卷、获取元数据信息 CLIENT整体架构QEMU： 实现了QEMU block与Client的对接层 向cinder/glance提供了Python API https://github.com/opencurve/curve-qemu-block-driver

© XXX Page 1 of 15 curvefs client 删除文件和目录功能设计© XXX Page 2 of 15 背景 相关调研 moosefs chubaofs 方案设计思考 1.Trash机制是实现1个(类似chubaofs)，还是2个（类似moosefs）？ 2. Trash放在哪里？ 3. 是否需要做session机制（在metaserver打开），来维护inode的打开情况？ 的打开情况？ 方案设计 Trash机制： Session机制： 遗留问题 工作量评估 背景 目前curvefs client版本对删除unlink和rmdir的设计只有简单的删除inode和dentry结构，遗留了nlink和lookup count相关的内容还未实现，是不完备的。本文首先调研moosefs，chubaofs等分布式系统，参考并设计解决上述遗留问题。 当前删除接口代码如下：© count需要减nlookup（forget的参数） 当umount时，所有lookup count减至0 不应该完全依赖forget接口去实现inode的移除，因为forget接口可能不会被内核调用（例如client崩溃） 相关调研 moosefs moosefs 未对接forget moosefs 实现了在mds上open，因此删除时可以判断文件是否被打开 moosefs使用了两种机制，来实现上述功

Guzzle Guzzle is a PHP HTTP client that makes it easy to send HTTP requests and trivial to integrate with web services. Manages things like persistent connections, represents query strings as collections the underlying HTTP transport layer. Can send both synchronous and asynchronous requests using the same interface without requiring a dependency on a specific event loop. Pluggable HTTP handlers allows integrate with any method you choose for sending HTTP requests over the wire (e.g., cURL, sockets, PHP’s stream wrapper, non-blocking event loops like React [http://reactphp.org/], etc.). Guzzle makes it so

index next | Guzzle 6 » Guzzle Documentation Guzzle is a PHP HTTP client that makes it easy to send HTTP requests and trivial to integrate with web services. Simple interface for building query strings strings, POST requests, streaming large uploads, streaming large downloads, using HTTP cookies, uploading JSON data, etc... Can send both synchronous and asynchronous requests using the same interface. Uses allows you to utilize other PSR-7 compatible libraries with Guzzle. Abstracts away the underlying HTTP transport, allowing you to write environment and transport agnostic code; i.e., no hard dependency

index next | Guzzle 6 » Guzzle Documentation Guzzle is a PHP HTTP client that makes it easy to send HTTP requests and trivial to integrate with web services. Simple interface for building query strings strings, POST requests, streaming large uploads, streaming large downloads, using HTTP cookies, uploading JSON data, etc... Can send both synchronous and asynchronous requests using the same interface. Uses allows you to utilize other PSR-7 compatible libraries with Guzzle. Abstracts away the underlying HTTP transport, allowing you to write environment and transport agnostic code; i.e., no hard dependency

index next | Guzzle 6 » Guzzle Documentation Guzzle is a PHP HTTP client that makes it easy to send HTTP requests and trivial to integrate with web services. Simple interface for building query strings strings, POST requests, streaming large uploads, streaming large downloads, using HTTP cookies, uploading JSON data, etc... Can send both synchronous and asynchronous requests using the same interface. Uses allows you to utilize other PSR-7 compatible libraries with Guzzle. Abstracts away the underlying HTTP transport, allowing you to write environment and transport agnostic code; i.e., no hard dependency

. . . . . . . . . . . . . . 54 2 HTTP Components 57 3 Service Description Commands 59 i ii Guzzle Guzzle is a PHP HTTP client that makes it easy to send HTTP requests and trivial to integrate with the underlying HTTP transport layer. • Can send both synchronous and asynchronous requests using the same interface without requiring a dependency on a specific event loop. • Pluggable HTTP handlers allows allows Guzzle to integrate with any method you choose for sending HTTP requests over the wire (e.g., cURL, sockets, PHP’s stream wrapper, non-blocking event loops like React, etc.). • Guzzle makes it so

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 1.3.14 http_errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 . . . . . . . . . . . . . . . . . . 46 ii Guzzle, Release Guzzle is a PHP HTTP client that makes it easy to send HTTP requests and trivial to integrate with web services. • Simple interface for building building query strings, POST requests, streaming large uploads, streaming large downloads, using HTTP cookies, uploading JSON data, etc... • Can send both synchronous and asynchronous requests using the