万亿量级实时数据库Tera - 集群调度系统Galaxy • 个人主页&Blog - https://github.com/bluebore - http://bluebore.cn 提纲 • 百度文件系统简介 • 分布式系统设计实践 • 总结与致谢 百度的集群环境 • 单个集群通常几千台机器 • 百度文件系统(BFS)、集群调度系统（Galaxy）、分布式协 调服务（Nexus）是核心服务 调服务（Nexus）是核心服务 • 实时任务与批量任务混合部署 Galaxy master BFS master Nexus lock service 分布式软件栈中的BFS The Baidu Stack 网络通信框架Sofa-pbrpc 分布式文件系统 BFS 集群调度系统 Galaxy 分布式协调服务 Nexus 分布式数据库 Tera 分布式计算框架 Shuttle App Apps(Spider/Index/Search) 数据中心操作系统(DCOS) • 进程调度&内存管理 - Galaxy - 应用部署和任务调度 • 锁和信号量 - Nexus - 分布式锁 - 分布式通知 • 文件系统 - The Baidu File System - 持久化存储 百度文件系统架构 设计一个分布式系统要考虑的 • 数据与计算的分片 • 分区故障容忍 • 数据一致性

['name' => 'iPhone 6S', 'brand' => 'Apple'], ], 'Samsung' => [ ['name' => 'Galaxy S7', 'brand' => 'Samsung'] ], ]); $products = $collection->flatten(1); $produc 'brand' => 'Apple'], ['name' => 'Galaxy S7', 'brand' => 'Samsung'], ] */ 在本例中，调用不提供深度的 flatten 方法也会对嵌套数组进行扁平化处理，返回结果 是 ['iPhone 6S', 'Apple', 'Galaxy S7', 'Samsung'] 。提供深度允许你严格设置被扁平化的数 组层级。 Watch', 'brand' => 'Apple', 'type' => 'watch '], ['name' => 'Galaxy S6', 'brand' => 'Samsung', 'type' => 'phone '], ['name' => 'Galaxy Gear', 'brand' => 'Samsung', 'type' => 'watc h'], ]); $unique

Watch', 'brand' => 'Apple', 'type' => 'wat ch'], ['name' => 'Galaxy S6', 'brand' => 'Samsung', 'type' => 'pho ne'], ['name' => 'Galaxy Gear', 'brand' => 'Samsung', 'type' => 'w atch'], ]); 本文档由 [ ['name' => 'iPhone 6', 'brand' => 'Apple', 'type' => 'ph one'], ['name' => 'Galaxy S6', 'brand' => 'Samsung', 'type' => 'phone'], ] */ 你还可以指定自己的回调用于判断数据项唯一性： $unique = 'brand' => 'Apple', 'type' => 'watch'], ['name' => 'Galaxy S6', 'brand' => 'Samsung', 'type' => 'phone'], ['name' => 'Galaxy Gear', 'brand' => 'Samsung', 'type' => 'watch'], ] */

['name' => 'iPhone 6S', 'brand' => 'Apple'], ], 'Samsung' => [ ['name' => 'Galaxy S7', 'brand' => 'Samsung'] ], ]); 本文档由 Laravel 学院提供 Laravel 学院致力于提供优质 Laravel 中文学 6S', 'brand' => 'Apple'], ['name' => 'Galaxy S7', 'brand' => 'Samsung'], ] */ 在本例中，调用不提供深度的 flatten 方法也会对嵌套数组进行扁平化处理，返回结果是 ['iPhone 6S', 'Apple', 'Galaxy S7', 'Samsung']。提供深度允许你严格设置被扁平化的数组层级。 Watch', 'brand' => 'Apple', 'type' => 'watch'], ['name' => 'Galaxy S6', 'brand' => 'Samsung', 'type' => 'phone'], ['name' => 'Galaxy Gear', 'brand' => 'Samsung', 'type' => 'watch'], ]); $unique

Watch', 'brand' => 'Apple', 'type' => 'wat ch'], ['name' => 'Galaxy S6', 'brand' => 'Samsung', 'type' => 'pho ne'], ['name' => 'Galaxy Gear', 'brand' => 'Samsung', 'type' => 'w atch'], ]); $unique [ ['name' => 'iPhone 6', 'brand' => 'Apple', 'type' => 'ph one'], ['name' => 'Galaxy S6', 'brand' => 'Samsung', 'type' => 'phone'], ] */ 你还可以指定自己的回调用于判断数据项唯一性： $unique = 'brand' => 'Apple', 'type' => 'watch'], ['name' => 'Galaxy S6', 'brand' => 'Samsung', 'type' => 'phone'], ['name' => 'Galaxy Gear', 'brand' => 'Samsung', 'type' => 'watch'], ] */

['name' => 'Galaxy S7', 'brand' => 'Samsung'] ], ]); $products = $collection->flatten(1); $products->values()->all(); /* [ ['name' => 'iPhone 6S', 'brand' => 'Apple'], ['name' => 'Galaxy S7', 'brand' 'brand' => 'Samsung'], ] */ 在本例中，调用不提供深度的 flatten 方法也会对嵌套数组进行扁 平化处理，返回结果是 ['iPhone 6S', 'Apple', 'Galaxy S7', 'Samsung']。提供深度允许你严格设置被扁平化的数组层级。 flip() flip 方法将集合的键值做交换： $collection = collect(['name' Watch', 'brand' => 'Apple', 'typ e' => 'watch'], ['name' => 'Galaxy S6', 'brand' => 'Samsung', 'typ e' => 'phone'], ['name' => 'Galaxy Gear', 'brand' => 'Samsung', 't ype' => 'watch'], ]); $unique

Source: Secret Lab Institute (CC-0 license) https://secretlab.institute/2021/02/15/cc-0-licensed-galaxy-brain-images/ 74© 2018 Bloomberg Finance L.P. All rights reserved. Now - time to go into my codebase

times. The advice printed in large, friendly letters on the cover of The Hitchhiker’s Guide to the Galaxy applies here: don’t panic. sorry The sorry proof command we encountered in Chapter 1 is also available

models should also be suitable: iOS: Apple iPad Air 1, Mini 4 Android: Sony Xperia Z2 Tablet, Samsung Galaxy Tab 4 Windows 10: Microsoft Surface We welcome feedback about specific devices. Your site’s frontend

models should also be suitable: iOS: Apple iPad Air 1, Mini 4 Android: Sony Xperia Z2 Tablet, Samsung Galaxy Tab 4 Windows 10: Microsoft Surface We welcome feedback about specific devices. Your site’s frontend