What’s New in Node.js v0.12 – Performance Optimizations The long development cycle for v0.12 (nine months and counting, the longest one to date) has given the core team and contributors ample opportunity to introduce a number of performance optimizations. This blog post aims to cover the most notable ones. Cork support for writable streams Writable streams now support a “corked” mode, similar to the TCP_CORK and TCP_NOPUSH socket options from `man tcp`. When corked, data written to the stream is queued up until the stream is uncorked again. The http module has been updated to use corked mode transparently when sending a chunked request or response body. TLS performance improvements The tls module has been considerably reworked in Node.js v0.12. In Node.js v0.10, the tls module sits on top of the net module as transform stream that transparently encrypts and decrypts network traffic. That is why in node.js v0.12, the tls module has been rewritten to use libuv directly. Most of the changes to the tls module should be transparent to end users.
ArangoDB - the multi-purpose NoSQL DB Moqups · Mockups, Wireframes & Prototyping Best Practices · angular/angular.js Wiki · GitHub Related: Anti-Patterns Namespace distributed code You shouldn't worry about prefixing internal code, but anything you plan to OpenSource should be namespaced The ng- is reserved for core directives.Purpose-namespacing (i18n- or geo-) is better than owner-namespacing (djs- or igor-)Checkout ui-alias to remove 3rd party prefixesOnly use .$broadcast(), . Stinger: Interactive Query for Apache Hive Apache Hive is the de facto standard for SQL-in-Hadoop with more enterprises relying on this open source project than any alternative. The Stinger Initiative is a broad, community-based effort to drive the future of Apache Hive, delivering 100x performance improvements at petabyte scale with familiar SQL semantics. Project Goals Speed Deliver interactive query through 100x performance increases as compared to Hive 10. Scale The only SQL interface to Hadoop designed for queries that scale from Terabytes to Petabytes. Support the broadest array of SQL semantics for analytic applications running in Hadoop. Status The Stinger initiative outlined three phases, and the Apache community delivered each on schedule. In the first phase of delivery, with HDP 1.3, we saw: Performance improvements of 35x-45x for common analytical queries andIntroduction of SQL windowing functions such as Rank, Lead, Lag, etc.Introduction of the ORCFile format Speed HDP 2.1 delivers Apache Hive 0.13 on Apache Tez. Scale
Lightweight javascript in-memory database: LokiJS Capturing Audio & Video in HTML5 Many browsers now have the ability to access video and audio input from the user. However, depending on the browser it might be a full dynamic and inline experience, or it could be delegated to another app on the user's device. On top of that, not every device even has a camera. Start simple and progressively If you want to progressively enhance your experience, you need to start with something that works everywhere. Ask for a URL This is the best supported but least satisfying option. Though, if you want to manipulate the image in any way, things are a bit more complicated. File input You can also use a simple file input element, including an accept filter that indicates you only want image files. This method works on all platforms. The data can then be attached to a <form> or manipulated with JavaScript by listening for an onchange event on the input element and then reading the files property of the event target. The files property is a FileList object, which I'll talk more about later.
Google's AngularJS Style Guide This is the external version of a document that was primarily written for Google engineers. It describes a recommended style for AngularJS apps that use Closure, as used internally at Google. Members of the broader AngularJS community should feel free to apply (or not apply) these recommendations, as relevant to their own use cases. This document describes style for AngularJS apps in google3. This guide supplements and extends the Google JavaScript Style Guide. Style Note: Examples on the AngularJS external webpage, and many external apps, are written in a style that freely uses closures, favors functional inheritance, and does not often use JavaScript types. 1 Angular Language Rules 2 Angular Style Rules 3 Angular Tips, Tricks, and Best Practices 4 Best practices links and docs 1 Angular Language Rules Manage dependencies with Closure's goog.require and goog.provide Choose a namespace for your project, and use goog.provide and goog.require. Why? Modules Why? For example: Why? JSCompiler Flags
OpenStack快速入门 - Jack Zhou的专栏 第一部分:OpenStack及其构成简介 一、云计算 云计算是一种计算模型,它将诸如运算能力、存储、网络和软件等资源抽象成为服务,以便让用户通过互联网远程享用,付费的形式也如同传统公共服务设施一样。因需而定、提供方便、动态改变和无限的虚拟化扩展能力是云计算的几个重要特征。 二、OpenStack概述 OpenStack是一整套开源软件项目的综合,它允许企业或服务提供者建立、运行自己的云计算和存储设施。 OpenStack的基本架构如下图: 图1 OpenStack基本构架 下图展示了Keystone、Dashboard二者与其它OpenStack部分的交互。 图2 OpenStack各组件的交互 三、OpenStack计算设施----Nova Nova是OpenStack计算的弹性控制器。 四、OpenStack镜像服务器----Glance OpenStack镜像服务器是一套虚拟机镜像发现、注册、检索系统,我们可以将镜像存储到以下任意一种存储中: (1)本地文件系统(默认) (2)OpenStack对象存储 (3)S3直接存储 (4)S3对象存储(作为S3访问的中间渠道) (5)HTTP(只读) 功能及特点:提供镜像相关服务 Glance构件:Glance控制器、Glance注册器 五、OpenStack存储设施----Swift Swift为OpenStack提供一种分布式、持续虚拟对象存储,它类似于Amazon Web Service的S3简单存储服务。 Swift组件:Swift代理、Swift对象、Swift容器、Swift账户、Swift RING。 六、OpenStack认证服务(Keystone) Keystone为所有的OpenStack组件提供认证和访问策略服务,它依赖自身REST(基于Identity API)系统进行工作,主要对(但不限于)Swift、Glance、Nova等进行认证与授权。 图3 Keystone的认证管理 Keystone采用两种授权方式,一种基于用户名/密码,另一种基于令牌(Token)。 第二部分:OpenStack安装与配置 一、引言 本章内容讲解如何在3台物理机上搭建最小化云平台,这3台机器分为称为Server1、Server2和Client1,之后的各章也是如此。 图4 OpenStack安装规划 图5 网络参数清单 图6 本教程网络设置参数
TaffyDB - The JavaScript Database