Click here to close now.

Welcome!

BigDataExpo® Blog Authors: Elizabeth White, Pat Romanski, Liz McMillan, Hovhannes Avoyan, Carmen Gonzalez

Blog Feed Post

Quick MapReduce with beanstalkd

At ProjectLocker, we operate a polyglot environment with a heavy Ruby bias. While we love Ruby and Rails, one of the drawbacks of Ruby is its Global VM Lock. In a nutshell, the Global VM Lock makes it harder to write Ruby code that can fully utilize a modern multi-core server. For Web applications, this isn’t a problem because the web server manages multiple processes for you (e.g. via Passenger). However, for offline processes, parallelism doesn’t come for free.

I was recently working on a project that involved the offline batch processing of lots of data. This project has been operating successfully for some time, but the data set has grown, causing the process to need more more time to complete than we’d like. So I dove in to see what we could do to speed it up. Fortunately, the process was still single-threaded, so we knew we’d be able to inject concurrency to increase throughput without adding hardware.

The job in question runs on a fairly well-equipped server, but the server was underutilized due to the process being serial. Here’s an outline of the initial code:

def main_job
  for retrieve_giant_dataset().each do |item|
    long_process(item)
  end

  summarize_results(retrieve_all_results()) 
end

def long_process(item)
  # Do some work on item that uses a lot of CPU time.
  item.save
end

That approach gets the job done, but I wanted to parallelize it. Conceptually, I wanted to transform the main_job method so that it looked something like this:

def main_job
  threads = []
  for retrieve_giant_dataset().each do |item|
    threads << Thread.new(item) do
      long_process(item)
    end
  end

  threads.each { |t| t.join }

  summarize_results(retrieve_all_results()) 
end

Unfortunately, it’s not that easy due to the aforementioned Global VM Lock. What I needed was a way to get my threads running on a bunch of independent processes. This is a problem tailor-made for a job queueing system. Enter beanstalkd, a simple & fast work queue. We paired beanstalkd with Stalker, a DSL that makes it easy to queue and process jobs from Ruby. Integrating these two was a cinch. Here’s what the restructured code looks like now:

def main_job
  for retrieve_giant_dataset().each do |item|
    Stalker.enqueue(JOB_NAME, :id => item.id)
  end

  beaneater = Beaneater::Pool.new(['localhost:11300'])
  tube = beaneater.tubes.find TUBE_NAME
  while tube.peek(:ready)
    sleep(5)
  end

  summarize_results(retrieve_all_results()) 
end

So instead of processing each item during the loop, now we just add each to the beanstalkd queue. Once we finish queueing all of the items, we wait until all of our entries have been processed by the worker processes. The workers are initiated via a jobs.rb file that looks something like this:

include Stalker
  
job JOB_NAME do |args|
  item = ItemClass.find(args['id'])
  Worker::long_process(item) 
end

We then start beanstalkd and a few worker processes and we’re off to the races. Now our job runs in parallel via multiple processes, and we can tune the number of worker processes we run to consume as much of the machine’s resources as we like. As a bonus, we can also run Stalker workers on other machines in our cluster for added parallelism. With just a few minor tweaks to our code, we’ve gone from single-threaded to a solution that is limited only by the capacity of the shared database used. Sweet!

What about the MapReduce reference in the title of this post? The MapReduce algorithm basically has two steps. In the Map step, you divide the work and assign it to worker nodes. The Reduce step simply combines the results of each individual node’s computation into an aggregate result. In our solution here, the Map step is done by us enqueuing our jobs into beanstalkd and then beanstalkd making the jobs available for consumption by our nodes. Our database serves to communicate the details of the jobs, and stands in for a shared filesystem like the HDFS used by Hadoop. I didn’t go into detail about this step, but our Reduce is also assisted by database aggregates; we’re able to construct a few simple queries that get us what we want from the database.

So there it is, distributed MapReduce for Ruby using beanstalkd, Stalker, and a healthy database. This is probably not the best solution if you need to scale to thousands or tens of thousands of workers. But if you just need to get tens of workers running in parallel quickly, you may be able to adapt this approach to fit your needs.

Read the original blog entry...

More Stories By Damon Young

Damon Young is Director of Sales at ProjectLocker.com. ProjectLocker was founded in 2003 to provide on-demand tools for software developers. Guided by the simple mission of helping companies build better software, ProjectLocker's services have expanded to include services for the complete lifecycle of software projects, from requirements documentation to build and test automation. ProjectLocker serves companies from startups to Fortune 1000 multinationals.

@BigDataExpo Stories
The OpenStack cloud operating system includes Trove, a database abstraction layer. Rather than applications connecting directly to a specific type of database, they connect to Trove, which in turn connects to one or more specific databases. One target database is Postgres Plus Cloud Database, which includes its own RESTful API. Trove was originally developed around MySQL, whose interfaces are significantly less complicated than those of the Postgres cloud database. In his session at 16th Cloud...
The web app is Agile. The REST API is Agile. The testing and planning are Agile. But alas, Data infrastructures certainly are not. Once an application matures, changing the shape or indexing scheme of data often forces at best a top down planning exercise and at worst includes schema changes which force downtime. The time has come for a new approach that fundamentally advances the agility of distributed data infrastructures. Come learn about a new solution to the problems faced by software orga...
In their general session at 16th Cloud Expo, Michael Piccininni, Global Account Manager – Cloud SP at EMC Corporation, and Mike Dietze, Regional Director at Windstream Hosted Solutions, will review next generation cloud services, including the Windstream-EMC Tier Storage solutions, and discuss how to increase efficiencies, improve service delivery and enhance corporate cloud solution development. Speaker Bios Michael Piccininni is Global Account Manager – Cloud SP at EMC Corporation. He has b...
There will be 150 billion connected devices by 2020. New digital businesses have already disrupted value chains across every industry. APIs are at the center of the digital business. You need to understand what assets you have that can be exposed digitally, what their digital value chain is, and how to create an effective business model around that value chain to compete in this economy. No enterprise can be complacent and not engage in the digital economy. Learn how to be the disruptor and not ...
The enterprise market will drive IoT device adoption over the next five years. In his session at @ThingsExpo, John Greenough, an analyst at BI Intelligence, division of Business Insider, will analyze how companies will adopt IoT products and the associated cost of adopting those products. John Greenough is the lead analyst covering the Internet of Things for BI Intelligence- Business Insider’s paid research service. Numerous IoT companies have cited his analysis of the IoT. Prior to joining B...
SYS-CON Events announced today that MetraTech, now part of Ericsson, has been named “Silver Sponsor” of SYS-CON's 16th International Cloud Expo®, which will take place on June 9–11, 2015, at the Javits Center in New York, NY. Ericsson is the driving force behind the Networked Society- a world leader in communications infrastructure, software and services. Some 40% of the world’s mobile traffic runs through networks Ericsson has supplied, serving more than 2.5 billion subscribers.
With major technology companies and startups seriously embracing IoT strategies, now is the perfect time to attend @ThingsExpo in Silicon Valley. Learn what is going on, contribute to the discussions, and ensure that your enterprise is as "IoT-Ready" as it can be! Internet of @ThingsExpo, taking place Nov 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with 17th Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading in...
The Internet of Things promises to transform businesses (and lives), but navigating the business and technical path to success can be difficult to understand. In his session at @ThingsExpo, Sean Lorenz, Technical Product Manager for Xively at LogMeIn, demonstrated how to approach creating broadly successful connected customer solutions using real world business transformation studies including New England BioLabs and more.
The world is at a tipping point where the technology, the device and global adoption are converging to such a point that we will see an explosion of a world where smartphone devices not only allow us to talk to each other, but allow for communication between everything – serving as a central hub from which we control our world – MediaTek is at the heart of both driving this and allowing the markets to drive this reality forward themselves. The next wave of consumer gadgets is here – smart, con...
It's time to face reality: "Americans are from Mars, Europeans are from Venus," and in today's increasingly connected world, understanding "inter-planetary" alignments and deviations is mission-critical for cloud. In her session at 15th Cloud Expo, Evelyn de Souza, Data Privacy and Compliance Strategy Leader at Cisco Systems, discussed cultural expectations of privacy based on new research across these elements
As enterprises engage with Big Data technologies to develop applications needed to meet operational demands, new computation fabrics are continually being introduced. To leverage these new innovations, organizations are sacrificing market opportunities to gain expertise in learning new systems. In his session at Big Data Expo, Supreet Oberoi, Vice President of Field Engineering at Concurrent, Inc., discussed how to leverage existing infrastructure and investments and future-proof them against e...
Due of the rise of Hadoop, many enterprises are now deploying their first small clusters of 10 to 20 servers. At this small scale, the complexity of operating the cluster looks and feels like general data center servers. It is not until the clusters scale, as they inevitably do, when the pain caused by the exponential complexity becomes apparent. We've seen this problem occur time and time again. In his session at Big Data Expo, Greg Bruno, Vice President of Engineering and co-founder of StackI...
You use an agile process; your goal is to make your organization more agile. But what about your data infrastructure? The truth is, today's databases are anything but agile - they are effectively static repositories that are cumbersome to work with, difficult to change, and cannot keep pace with application demands. Performance suffers as a result, and it takes far longer than it should to deliver new features and capabilities needed to make your organization competitive. As your application an...
17th Cloud Expo, taking place Nov 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA, will feature technical sessions from a rock star conference faculty and the leading industry players in the world. Cloud computing is now being embraced by a majority of enterprises of all sizes. Yesterday's debate about public vs. private has transformed into the reality of hybrid cloud: a recent survey shows that 74% of enterprises have a hybrid cloud strategy. Meanwhile, 94% of enterprises a...
Move from reactive to proactive cloud management in a heterogeneous cloud infrastructure. In his session at 16th Cloud Expo, Manoj Khabe, Innovative Solution-Focused Transformation Leader at Vicom Computer Services, Inc., will show how to replace a help desk-centric approach with an ITIL-based service model and service-centric CMDB that’s tightly integrated with an event and incident management platform. Learn how to expand the scope of operations management to service management. He will al...
The true value of the Internet of Things (IoT) lies not just in the data, but through the services that protect the data, perform the analysis and present findings in a usable way. With many IoT elements rooted in traditional IT components, Big Data and IoT isn’t just a play for enterprise. In fact, the IoT presents SMBs with the prospect of launching entirely new activities and exploring innovative areas. CompTIA research identifies several areas where IoT is expected to have the greatest impac...
SAP is delivering break-through innovation combined with fantastic user experience powered by the market-leading in-memory technology, SAP HANA. In his General Session at 15th Cloud Expo, Thorsten Leiduck, VP ISVs & Digital Commerce, SAP, discussed how SAP and partners provide cloud and hybrid cloud solutions as well as real-time Big Data offerings that help companies of all sizes and industries run better. SAP launched an application challenge to award the most innovative SAP HANA and SAP HANA...
Explosive growth in connected devices. Enormous amounts of data for collection and analysis. Critical use of data for split-second decision making and actionable information. All three are factors in making the Internet of Things a reality. Yet, any one factor would have an IT organization pondering its infrastructure strategy. How should your organization enhance its IT framework to enable an Internet of Things implementation? In his session at Internet of @ThingsExpo, James Kirkland, Chief Ar...
The security devil is always in the details of the attack: the ones you've endured, the ones you prepare yourself to fend off, and the ones that, you fear, will catch you completely unaware and defenseless. The Internet of Things (IoT) is nothing if not an endless proliferation of details. It's the vision of a world in which continuous Internet connectivity and addressability is embedded into a growing range of human artifacts, into the natural world, and even into our smartphones, appliances, a...
All major researchers estimate there will be tens of billions devices - computers, smartphones, tablets, and sensors - connected to the Internet by 2020. This number will continue to grow at a rapid pace for the next several decades. With major technology companies and startups seriously embracing IoT strategies, now is the perfect time to attend @ThingsExpo, June 9-11, 2015, at the Javits Center in New York City. Learn what is going on, contribute to the discussions, and ensure that your enter...