Modeling and Analyzing Latency in the Memcached System
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4€€€€An Encyclopedia with Breaking News
Wikipedia @ 20 • ::Wikipedia @ 20 4 An Encyclopedia with Breaking News Brian Keegan Published on: Oct 15, 2020 Updated on: Nov 16, 2020 License: Creative Commons Attribution 4.0 International License (CC-BY 4.0) Wikipedia @ 20 • ::Wikipedia @ 20 4 An Encyclopedia with Breaking News Wikipedia’s response to the September 11 attacks profoundly shaped its rules and identity and illuminated a new strategy for growing the project by coupling the supply and demand for information about news. Wikipedia’s breaking news collaborations offer lessons for hardening other online platforms against polarization, disinformation, and other sociotechnical sludge. The web was a very different place for news in the United States between 2001 and 2006. The hanging chads from the 2000 presidential election, the spectacular calamity of 9/11, the unrepentant lies around Operation Iraqi Freedom, and the campy reality television featuring Donald Trump were all from this time. The burst of the dot-com bubble and corporate malfeasance of companies like Enron dampened entrepreneurial spirits, news publishers were optimistically sharing their stories online without paywalls, and blogging was heralded as the future of technology-mediated accountability and participatory democracy. “You” was Time Magazine’s Person of the Year in 2006 because “Web 2.0” platforms like YouTube, MySpace, and Second Life had become tools for “bringing together the small contributions of millions of people and making them matter.”1 Wikipedia was a part of this primordial soup, predating news-feed-mediated engagement, recommender-driven polarization, politicized content moderation, and geopolitical disinformation campaigns. From very early in its history, Wikipedia leveraged the supply and demand for information about breaking news and current events into strategies that continue to sustain this radical experiment in online peer production. -
Redis and Memcached
Redis and Memcached Speaker: Vladimir Zivkovic, Manager, IT June, 2019 Problem Scenario • Web Site users wanting to access data extremely quickly (< 200ms) • Data being shared between different layers of the stack • Cache a web page sessions • Research and test feasibility of using Redis as a solution for storing and retrieving data quickly • Load data into Redis to test ETL feasibility and Performance • Goal - get sub-second response for API calls for retrieving data !2 Why Redis • In-memory key-value store, with persistence • Open source • Written in C • It can handle up to 2^32 keys, and was tested in practice to handle at least 250 million of keys per instance.” - http://redis.io/topics/faq • Most popular key-value store - http://db-engines.com/en/ranking !3 History • REmote DIctionary Server • Released in 2009 • Built in order to scale a website: http://lloogg.com/ • The web application of lloogg was an ajax app to show the site traffic in real time. Needed a DB handling fast writes, and fast ”get latest N items” operation. !4 Redis Data types • Strings • Bitmaps • Lists • Hyperlogs • Sets • Geospatial Indexes • Sorted Sets • Hashes !5 Redis protocol • redis[“key”] = “value” • Values can be strings, lists or sets • Push and pop elements (atomic) • Fetch arbitrary set and array elements • Sorting • Data is written to disk asynchronously !6 Memory Footprint • An empty instance uses ~ 3MB of memory. • For 1 Million small Keys => String Value pairs use ~ 85MB of memory. • 1 Million Keys => Hash value, representing an object with 5 fields, -
Release 2.5.5 Ask Solem Contributors
Celery Documentation Release 2.5.5 Ask Solem Contributors February 04, 2014 Contents i ii Celery Documentation, Release 2.5.5 Contents: Contents 1 Celery Documentation, Release 2.5.5 2 Contents CHAPTER 1 Getting Started Release 2.5 Date February 04, 2014 1.1 Introduction Version 2.5.5 Web http://celeryproject.org/ Download http://pypi.python.org/pypi/celery/ Source http://github.com/celery/celery/ Keywords task queue, job queue, asynchronous, rabbitmq, amqp, redis, python, webhooks, queue, dis- tributed – • Synopsis • Overview • Example • Features • Documentation • Installation – Bundles – Downloading and installing from source – Using the development version 1.1.1 Synopsis Celery is an open source asynchronous task queue/job queue based on distributed message passing. Focused on real- time operation, but supports scheduling as well. The execution units, called tasks, are executed concurrently on one or more worker nodes using multiprocessing, Eventlet or gevent. Tasks can execute asynchronously (in the background) or synchronously (wait until ready). Celery is used in production systems to process millions of tasks every hour. 3 Celery Documentation, Release 2.5.5 Celery is written in Python, but the protocol can be implemented in any language. It can also operate with other languages using webhooks. There’s also RCelery for the Ruby programming language, and a PHP client. The recommended message broker is RabbitMQ, but support for Redis, MongoDB, Beanstalk, Amazon SQS, CouchDB and databases (using SQLAlchemy or the Django ORM) is also available. Celery is easy to integrate with web frameworks, some of which even have integration packages: Django django-celery Pyramid pyramid_celery Pylons celery-pylons Flask flask-celery web2py web2py-celery 1.1.2 Overview This is a high level overview of the architecture. -
Writing History in the Digital Age
:ULWLQJ+LVWRU\LQWKH'LJLWDO$JH -DFN'RXJKHUW\.ULVWHQ1DZURW]NL 3XEOLVKHGE\8QLYHUVLW\RI0LFKLJDQ3UHVV -DFN'RXJKHUW\DQG.ULVWHQ1DZURW]NL :ULWLQJ+LVWRU\LQWKH'LJLWDO$JH $QQ$UERU8QLYHUVLW\RI0LFKLJDQ3UHVV 3URMHFW086( :HE6HSKWWSPXVHMKXHGX For additional information about this book http://muse.jhu.edu/books/9780472029914 Access provided by University of Notre Dame (10 Jan 2016 18:25 GMT) 2RPP The Wikiblitz A Wikipedia Editing Assignment in a First- Year Undergraduate Class Shawn Graham In this essay, I describe an experiment conducted in the 2010 academic year at Carleton University, in my first- year seminar class on digital his- tory. This experiment was designed to explore how knowledge is created and represented on Wikipedia, by working to improve a single article. The overall objective of the class was to give students an understanding of how historians can create “signal” in the “noise” of the Internet and how historians create knowledge using digital media tools. Given that doing “research” online often involves selecting a resource suggested by Google (generally one within the first three to five results),1 this class had larger media literacy goals as well. The students were drawn from all areas of the university, with the only stipulation being that they had to be in their first year. The positive feedback loops inherent in the World Wide Web’s struc- ture greatly influence the way history is consumed, disseminated, and cre- ated online. Google’s algorithms will retrieve an article from Wikipedia, typically displaying it as one of the first links on the results page. Some- one somewhere will decide that the information is “wrong,” and he (it is typically a he)2 will “fix” the information, clicking on the “edit” button to make the change. -
An End-To-End Application Performance Monitoring Tool
Applications Manager - an end-to-end application performance monitoring tool For enterprises to stay ahead of the technology curve in today's competitive IT environment, it is important for their business critical applications to perform smoothly. Applications Manager - ManageEngine's on-premise application performance monitoring solution offers real-time application monitoring capabilities that offer deep visibility into not only the performance of various server and infrastructure components but also other technologies used in the IT ecosystem such as databases, cloud services, virtual systems, application servers, web server/services, ERP systems, big data, middleware and messaging components, etc. Highlights of Applications Manager Wide range of supported apps Monitor 150+ application types and get deep visibility into all the components of your application environment. Ensure optimal performance of all your applications by visualizing real-time data via comprehensive dashboards and reports. Easy installation and setup Get Applications Manager running in under two minutes. Applications Manager is an agentless monitoring tool and it requires no complex installation procedures. Automatic discovery and dependency mapping Automatically discover all applications and servers in your network and easily categorize them based on their type (apps, servers, databases, VMs, etc.). Get comprehensive insight into your business infrastructure, drill down to IT application relationships, map them effortlessly and understand how applications interact with each other with the help of these dependency maps. Deep dive performance metrics Track key performance metrics of your applications like response times, requests per minute, lock details, session details, CPU and disk utilization, error states, etc. Measure the efficiency of your applications by visualizing the data at regular periodic intervals. -
The Culture of Wikipedia
Good Faith Collaboration: The Culture of Wikipedia Good Faith Collaboration The Culture of Wikipedia Joseph Michael Reagle Jr. Foreword by Lawrence Lessig The MIT Press, Cambridge, MA. Web edition, Copyright © 2011 by Joseph Michael Reagle Jr. CC-NC-SA 3.0 Purchase at Amazon.com | Barnes and Noble | IndieBound | MIT Press Wikipedia's style of collaborative production has been lauded, lambasted, and satirized. Despite unease over its implications for the character (and quality) of knowledge, Wikipedia has brought us closer than ever to a realization of the centuries-old Author Bio & Research Blog pursuit of a universal encyclopedia. Good Faith Collaboration: The Culture of Wikipedia is a rich ethnographic portrayal of Wikipedia's historical roots, collaborative culture, and much debated legacy. Foreword Preface to the Web Edition Praise for Good Faith Collaboration Preface Extended Table of Contents "Reagle offers a compelling case that Wikipedia's most fascinating and unprecedented aspect isn't the encyclopedia itself — rather, it's the collaborative culture that underpins it: brawling, self-reflexive, funny, serious, and full-tilt committed to the 1. Nazis and Norms project, even if it means setting aside personal differences. Reagle's position as a scholar and a member of the community 2. The Pursuit of the Universal makes him uniquely situated to describe this culture." —Cory Doctorow , Boing Boing Encyclopedia "Reagle provides ample data regarding the everyday practices and cultural norms of the community which collaborates to 3. Good Faith Collaboration produce Wikipedia. His rich research and nuanced appreciation of the complexities of cultural digital media research are 4. The Puzzle of Openness well presented. -
WEB2PY Enterprise Web Framework (2Nd Edition)
WEB2PY Enterprise Web Framework / 2nd Ed. Massimo Di Pierro Copyright ©2009 by Massimo Di Pierro. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning, or otherwise, except as permitted under Section 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923, (978) 750-8400, fax (978) 646-8600, or on the web at www.copyright.com. Requests to the Copyright owner for permission should be addressed to: Massimo Di Pierro School of Computing DePaul University 243 S Wabash Ave Chicago, IL 60604 (USA) Email: [email protected] Limit of Liability/Disclaimer of Warranty: While the publisher and author have used their best efforts in preparing this book, they make no representations or warranties with respect to the accuracy or completeness of the contents of this book and specifically disclaim any implied warranties of merchantability or fitness for a particular purpose. No warranty may be created ore extended by sales representatives or written sales materials. The advice and strategies contained herein may not be suitable for your situation. You should consult with a professional where appropriate. Neither the publisher nor author shall be liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages. Library of Congress Cataloging-in-Publication Data: WEB2PY: Enterprise Web Framework Printed in the United States of America. -
Performance at Scale with Amazon Elasticache
Performance at Scale with Amazon ElastiCache July 2019 Notices Customers are responsible for making their own independent assessment of the information in this document. This document: (a) is for informational purposes only, (b) represents current AWS product offerings and practices, which are subject to change without notice, and (c) does not create any commitments or assurances from AWS and its affiliates, suppliers or licensors. AWS products or services are provided “as is” without warranties, representations, or conditions of any kind, whether express or implied. The responsibilities and liabilities of AWS to its customers are controlled by AWS agreements, and this document is not part of, nor does it modify, any agreement between AWS and its customers. © 2019 Amazon Web Services, Inc. or its affiliates. All rights reserved. Contents Introduction .......................................................................................................................... 1 ElastiCache Overview ......................................................................................................... 2 Alternatives to ElastiCache ................................................................................................. 2 Memcached vs. Redis ......................................................................................................... 3 ElastiCache for Memcached ............................................................................................... 5 Architecture with ElastiCache for Memcached ............................................................... -
High Performance with Distributed Caching
High Performance with Distributed Caching Key Requirements For Choosing The Right Solution High Performance with Distributed Caching: Key Requirements for Choosing the Right Solution Table of Contents Executive summary 3 Companies are choosing Couchbase for their caching layer, and much more 3 Memory-first 4 Persistence 4 Elastic scalability 4 Replication 5 More than caching 5 About this guide 5 Memcached and Oracle Coherence – two popular caching solutions 6 Oracle Coherence 6 Memcached 6 Why cache? Better performance, lower costs 6 Common caching use cases 7 Key requirements for an effective distributed caching solution 8 Problems with Oracle Coherence: cost, complexity, capabilities 8 Memcached: A simple, powerful open source cache 10 Lack of enterprise support, built-in management, and advanced features 10 Couchbase Server as a high-performance distributed cache 10 General-purpose NoSQL database with Memcached roots 10 Meets key requirements for distributed caching 11 Develop with agility 11 Perform at any scale 11 Manage with ease 12 Benchmarks: Couchbase performance under caching workloads 12 Simple migration from Oracle Coherence or Memcached to Couchbase 13 Drop-in replacement for Memcached: No code changes required 14 Migrating from Oracle Coherence to Couchbase Server 14 Beyond caching: Simplify IT infrastructure, reduce costs with Couchbase 14 About Couchbase 14 Caching has become Executive Summary a de facto technology to boost application For many web, mobile, and Internet of Things (IoT) applications that run in clustered performance as well or cloud environments, distributed caching is a key requirement, for reasons of both as reduce costs. performance and cost. By caching frequently accessed data in memory – rather than making round trips to the backend database – applications can deliver highly responsive experiences that today’s users expect. -
Opinnäytetyön Malli Vanhoille Word-Versioille
Bachelor’s Thesis Information Technology 2011 Kenneth Emeka Odoh DESIGN AND IMPLEMENTATION OF A WEB- BASED AUCTION SYSTEM ii BACHELOR’S THESIS (UAS) │ABSTRACT TURKU UNIVERSITY OF APPLIED SCIENCES Information Technology | Networking Date of completion of the thesis | 12th January 2012 Instructor: Ferm Tiina Kenneth Emeka Odoh DESIGN AND IMPLEMENTATION OF A WEB- BASED AUCTION SYSTEM Electronic auction has been a popular means of goods distribution. The number of items sold through the internet auction sites have grown in the past few years. Evidently, this has become the medium of choice for customers. This project entails the design and implementation of a web-based auction system for users to trade in goods. The system was implemented in the Django framework. On account that the trade over the Internet lacks any means of ascertaining the quality of goods, there is a need to implement a feedback system to rate the seller’s credibility in order to increase customer confidence in a given business. The feedback system is based on the history of the customer’s rating of the previous seller’s transactions. As a result, the auction system has a built-in feedback system to enhance the credibility of the auction system. The project was designed by using a modular approach to ensure maintainability. There is a number of engines that were implemented in order to enhance the functionality of the auction system. They include the following: commenting engine, search engine, business intelligence (user analytic and statistics), graph engine, advertisement engine and recommendation engine. As a result of this thesis undertaking, a full-fledged system robust enough to handle small or medium-sized traffic has been developed to specification. -
Seniors' Stories | Volume 4
Seniors’ Stories Seniors’ Stories Volume 4 Volume Volume 4 FRONT COVER: OPEN CATEGORY WINNING ENTRY Angus Lee Forbes Ilona was named after her Great Grandmother, a truly great woman. Born in Hungary, she arrived in Australia during the onset of World War Two. Ninety years and four generations separate the two. Connected by name, both adore spending time with one another. Acknowledgements This collection of 100 stories is the fourth volume of Seniors Stories written by seniors from throughout NSW. The theme of this year’s edition was positive ageing and each story reflects this theme in its own unique and inspiring way. NSW Seniors Card would like to thank the 100 authors whose stories are published in this volume of Seniors Stories, as well as the many other seniors who contributed to the overwhelming number and quality of stories received. Thanks also to contributing editor, Colleen Parker, Fellowship of Australian Writers NSW, and those involved in the design and printing of the book. Seniors’ Stories – Volume 4 1 A message from the Premier Welcome to the fourth edition of Seniors’ Stories. Older people have an extraordinary influence on our The stories in this publication are a great example community; they are the backbone of many of our of the wisdom, talent and ability of our extraordinary voluntary organisations and play a vital role in our seniors in NSW. families and neighbourhoods. The theme of this year’s book is Positive Ageing Seniors’ Stories is just one way of recognising and and the stories showcase the vast range of positive valuing the experiences of older people in NSW experiences and invaluable contributions that older and building connections between young and old. -
VSI's Open Source Strategy
VSI's Open Source Strategy Plans and schemes for Open Source so9ware on OpenVMS Bre% Cameron / Camiel Vanderhoeven April 2016 AGENDA • Programming languages • Cloud • Integraon technologies • UNIX compability • Databases • Analy;cs • Web • Add-ons • Libraries/u;li;es • Other consideraons • SoDware development • Summary/conclusions tools • Quesons Programming languages • Scrip;ng languages – Lua – Perl (probably in reasonable shape) – Tcl – Python – Ruby – PHP – JavaScript (Node.js and friends) – Also need to consider tools and packages commonly used with these languages • Interpreted languages – Scala (JVM) – Clojure (JVM) – Erlang (poten;ally a good fit with OpenVMS; can get good support from ESL) – All the above are seeing increased adop;on 3 Programming languages • Compiled languages – Go (seeing rapid adop;on) – Rust (relavely new) – Apple Swi • Prerequisites (not all are required in all cases) – LLVM backend – Tweaks to OpenVMS C and C++ compilers – Support for latest language standards (C++) – Support for some GNU C/C++ extensions – Updates to OpenVMS C RTL and threads library 4 Programming languages 1. JavaScript 2. Java 3. PHP 4. Python 5. C# 6. C++ 7. Ruby 8. CSS 9. C 10. Objective-C 11. Perl 12. Shell 13. R 14. Scala 15. Go 16. Haskell 17. Matlab 18. Swift 19. Clojure 20. Groovy 21. Visual Basic 5 See h%p://redmonk.com/sogrady/2015/07/01/language-rankings-6-15/ Programming languages Growing programming languages, June 2015 Steve O’Grady published another edi;on of his great popularity study on programming languages: RedMonk Programming Language Rankings: June 2015. As usual, it is a very valuable piece. There are many take-away from this research.