Welcome!

@DXWorldExpo Authors: Yeshim Deniz, Ed Featherston, Dalibor Siroky, Rostyslav Demush, Elizabeth White

Related Topics: @DXWorldExpo, Apache

@DXWorldExpo: Blog Post

An Example to Illustrate Hadoop Code Reuse

The developer tool to realize Hadoop code reuse

The MapReduce of Hadoop is a widely-used parallel computing framework. However, its code reuse mechanism is inconvenient, and it is quite cumbersome to pass parameters. Far different from our usual experience of calling the library function easily, I found both the coder and the caller must bear a sizable amount of precautions in mind when writing even a short pieces of program for calling by others.

However, we finally find that esProc could easily realize code reuse in hadoop. Still a simple and understandable example of grouping and summarizing, let's check out a solution with not so great reusability. Suppose we need to group the big data of order (sales.txt) on HDFS by salesman (empID), and seek the corresponding sales amount of each Salesman. esProc codes are:
Code for summary machine:



Code for node machine:



esProc classifies the distributed computing into two categories: The respective codes for summary machine and node machine. The summary machine is responsible for task scheduling, distributing the task to every task in the form of parameter, and finally integrating and summarizing the computing results from node machines. The node machines are used to get a segment of the whole data piece as specified by parameters, and then group and summarize the data of this segment.

As can be seen, esProc code is intuitive and straightforward, just like the natural and common thinking patterns. The summary machine distributes a task into several segments; distributes them to the unit machine to summarize initially; and then further summarizes the summary machine for the second time. Another thing to note is the esProc grouping and summarizing function "groups", which is used to perform the grouping action over the two-dimensional table A1 by empID and sum up the values of amount fields. The result will be renamed to the understandable totalAmount. This whole procedure of grouping and summarizing is quite concise and intuitive: A1.groups(empID;sum(amount): totalAmount)

In addition, the groups function can be applied to not only the small 2D table, but also the 2D table that is too great to be held in the memory. For example, the cursor mode is adopted for the above codes.

But there are some obvious defects in the above example: The reusability of code is not great. In the steps followed, we will rewrite the above example to a universal algorithm independent of any concrete business. It will be rewritten to control the code flow with parameters, so as to summarize whatsoever data file. In which, the task granularity can be scheduled into arbitrary number of segments, and the computing nodes can be specified at will. Then, the revised codes are shown below:

Code for summary machine. There are altogether 4 parameters defined here: fileName: Big data file to analyze; taskNumber: Number of tasks to distribute; groupField: Fields to group; sumField: Fields to summarize. In addition, the node machine is obtained via reading the profiles.



Code for node machine. In the revised codes, 4 variables are used to receive the parameter from summary machine. Besides the file starting and ending positions (start and end) from the first example, there are two newly-added fields. They are groupField: Fields to group; and sumField: Fields to summarize.



In esProc, it is much easier to pass and use parameter because users can implement the common grouping and summarizing with the least modification workload, and reuse the codes easily.

In Hadoop, the complicated business algorithm is mainly implemented by writing the MapReduce class. By comparison, it is much more inflexible to pass and use parameters in MapReduce. Though it is possible to implement a flexible algorithm independent of the concrete business, it is really cumbersome. Judging the Hadoop codes, the coupling degree of code and business is great. To pass the parameters, a global-variable-like mechanism is required, which is not only inconvenient but also hard to understand. That's why so many questions about MapReduce parameter-passing are here and there on many Web pages. Lots of people feel confused about developing universal algorithms with MapReduce.

In addition, the default separator in the above codes is the comma. It is obvious that users only need to add a variable in a similar way to customize it to any more commonly-used symbol. With it, they can also implement the common action of data filtering and then grouping and summarizing easily. Please note the usage of parameter groupField. It is used as the character parameter in the cell A6, but the macro in A8. In other words, ${gruopField} can be resolved as the formula itself, instead of any parameter in the formula alone. This is the work of dynamic language. Therefore, esProc can realize the completely flexible code, for example, using the parameter to control the summary algorithm to perform sum up or just count, seek the average value or maximum.

"Macro" is a simple special case of dynamic language. esProc supports a more flexible and complete dynamic language system.

As you may find from the above example, esProc can implement Hadoop code reuse easily, and basically achieve the goal of "Write once, run anywhere!". Needless to say, the development efficiency can be boosted dramatically.

personal blog: http://datakeyword.blogspot.com/

website: http://www.raqsoft.com/

More Stories By Jessica Qiu

Jessica Qiu is the editor of Raqsoft. She provides press releases for data computation and data analytics.

@BigDataExpo Stories
In his keynote at 18th Cloud Expo, Andrew Keys, Co-Founder of ConsenSys Enterprise, provided an overview of the evolution of the Internet and the Database and the future of their combination – the Blockchain. Andrew Keys is Co-Founder of ConsenSys Enterprise. He comes to ConsenSys Enterprise with capital markets, technology and entrepreneurial experience. Previously, he worked for UBS investment bank in equities analysis. Later, he was responsible for the creation and distribution of life settle...
Product connectivity goes hand and hand these days with increased use of personal data. New IoT devices are becoming more personalized than ever before. In his session at 22nd Cloud Expo | DXWorld Expo, Nicolas Fierro, CEO of MIMIR Blockchain Solutions, will discuss how in order to protect your data and privacy, IoT applications need to embrace Blockchain technology for a new level of product security never before seen - or needed.
Leading companies, from the Global Fortune 500 to the smallest companies, are adopting hybrid cloud as the path to business advantage. Hybrid cloud depends on cloud services and on-premises infrastructure working in unison. Successful implementations require new levels of data mobility, enabled by an automated and seamless flow across on-premises and cloud resources. In his general session at 21st Cloud Expo, Greg Tevis, an IBM Storage Software Technical Strategist and Customer Solution Architec...
Coca-Cola’s Google powered digital signage system lays the groundwork for a more valuable connection between Coke and its customers. Digital signs pair software with high-resolution displays so that a message can be changed instantly based on what the operator wants to communicate or sell. In their Day 3 Keynote at 21st Cloud Expo, Greg Chambers, Global Group Director, Digital Innovation, Coca-Cola, and Vidya Nagarajan, a Senior Product Manager at Google, discussed how from store operations and ...
Blockchain is a shared, secure record of exchange that establishes trust, accountability and transparency across business networks. Supported by the Linux Foundation's open source, open-standards based Hyperledger Project, Blockchain has the potential to improve regulatory compliance, reduce cost as well as advance trade. Are you curious about how Blockchain is built for business? In her session at 21st Cloud Expo, René Bostic, Technical VP of the IBM Cloud Unit in North America, discussed the b...
You know you need the cloud, but you’re hesitant to simply dump everything at Amazon since you know that not all workloads are suitable for cloud. You know that you want the kind of ease of use and scalability that you get with public cloud, but your applications are architected in a way that makes the public cloud a non-starter. You’re looking at private cloud solutions based on hyperconverged infrastructure, but you’re concerned with the limits inherent in those technologies.
Imagine if you will, a retail floor so densely packed with sensors that they can pick up the movements of insects scurrying across a store aisle. Or a component of a piece of factory equipment so well-instrumented that its digital twin provides resolution down to the micrometer.
A strange thing is happening along the way to the Internet of Things, namely far too many devices to work with and manage. It has become clear that we'll need much higher efficiency user experiences that can allow us to more easily and scalably work with the thousands of devices that will soon be in each of our lives. Enter the conversational interface revolution, combining bots we can literally talk with, gesture to, and even direct with our thoughts, with embedded artificial intelligence, whic...
Sanjeev Sharma Joins June 5-7, 2018 @DevOpsSummit at @Cloud Expo New York Faculty. Sanjeev Sharma is an internationally known DevOps and Cloud Transformation thought leader, technology executive, and author. Sanjeev's industry experience includes tenures as CTO, Technical Sales leader, and Cloud Architect leader. As an IBM Distinguished Engineer, Sanjeev is recognized at the highest levels of IBM's core of technical leaders.
When it comes to cloud computing, the ability to turn massive amounts of compute cores on and off on demand sounds attractive to IT staff, who need to manage peaks and valleys in user activity. With cloud bursting, the majority of the data can stay on premises while tapping into compute from public cloud providers, reducing risk and minimizing need to move large files. In his session at 18th Cloud Expo, Scott Jeschonek, Director of Product Management at Avere Systems, discussed the IT and busine...
It’s conference season and, as you might expect, Jason and I have been on the road covering a bunch of them. It’s always great to see what the disruptive players in the market are doing — and this year did not disappoint. But there is one thing that repeatedly happens that just gets under my skin: transformation-washing. As Jason explained in a Forbes article over a year ago, ‘washing’ is when a vendor (or pundit) applies a buzzword loosely in an overt attempt to attach themselves to its buzz. ...
As many know, the first generation of Cloud Management Platform (CMP) solutions were designed for managing virtual infrastructure (IaaS) and traditional applications. But that's no longer enough to satisfy evolving and complex business requirements. In his session at 21st Cloud Expo, Scott Davis, Embotics CTO, explored how next-generation CMPs ensure organizations can manage cloud-native and microservice-based application architectures, while also facilitating agile DevOps methodology. He expla...
In a recent survey, Sumo Logic surveyed 1,500 customers who employ cloud services such as Amazon Web Services (AWS), Microsoft Azure, and Google Cloud Platform (GCP). According to the survey, a quarter of the respondents have already deployed Docker containers and nearly as many (23 percent) are employing the AWS Lambda serverless computing framework. It’s clear: serverless is here to stay. The adoption does come with some needed changes, within both application development and operations. Tha...
Widespread fragmentation is stalling the growth of the IIoT and making it difficult for partners to work together. The number of software platforms, apps, hardware and connectivity standards is creating paralysis among businesses that are afraid of being locked into a solution. EdgeX Foundry is unifying the community around a common IoT edge framework and an ecosystem of interoperable components.
DX World EXPO, LLC, a Lighthouse Point, Florida-based startup trade show producer and the creator of "DXWorldEXPO® - Digital Transformation Conference & Expo" has announced its executive management team. The team is headed by Levent Selamoglu, who has been named CEO. "Now is the time for a truly global DX event, to bring together the leading minds from the technology world in a conversation about Digital Transformation," he said in making the announcement.
In this strange new world where more and more power is drawn from business technology, companies are effectively straddling two paths on the road to innovation and transformation into digital enterprises. The first path is the heritage trail – with “legacy” technology forming the background. Here, extant technologies are transformed by core IT teams to provide more API-driven approaches. Legacy systems can restrict companies that are transitioning into digital enterprises. To truly become a lead...
Digital Transformation (DX) is not a "one-size-fits all" strategy. Each organization needs to develop its own unique, long-term DX plan. It must do so by realizing that we now live in a data-driven age, and that technologies such as Cloud Computing, Big Data, the IoT, Cognitive Computing, and Blockchain are only tools. In her general session at 21st Cloud Expo, Rebecca Wanta explained how the strategy must focus on DX and include a commitment from top management to create great IT jobs, monitor ...
A few years ago – in the early days of Blockchain – a lot of people were taken with the idea of a multifunctional chain on which all transactions could be handled. After Ethereum was launched in 2014, its advocates were talking themselves hoarse about the transformative opportunities the platform introduced. Decentralized applications, they predicted, along with all sorts of value transfers would be executed exclusively on Ethereum from that point on, and no other networks would ever be needed....
DevOps promotes continuous improvement through a culture of collaboration. But in real terms, how do you: Integrate activities across diverse teams and services? Make objective decisions with system-wide visibility? Use feedback loops to enable learning and improvement? With technology insights and real-world examples, in his general session at @DevOpsSummit, at 21st Cloud Expo, Andi Mann, Chief Technology Advocate at Splunk, explored how leading organizations use data-driven DevOps to close th...
The IoT Will Grow: In what might be the most obvious prediction of the decade, the IoT will continue to expand next year, with more and more devices coming online every single day. What isn’t so obvious about this prediction: where that growth will occur. The retail, healthcare, and industrial/supply chain industries will likely see the greatest growth. Forrester Research has predicted the IoT will become “the backbone” of customer value as it continues to grow. It is no surprise that retail is ...