Welcome!

Big Data Journal Authors: Elizabeth White, Pat Romanski, Richard Moulds, Martin Etmajer, Roger Strukhoff

Related Topics: SOA & WOA, Java, Linux, Web 2.0, Security, Big Data Journal

SOA & WOA: Article

Twitter’s Story: How Homegrown Load Testing Tools Can Misfire

If Twitter built their own tool to perform their own load test, why did the selfie cause their site to crash?

The selfie that changed the world, or at least Twitter, has been in the news for the past month. On March 2, 2014, the infamous Oscar selfie of Ellen and her celebrity friends broke a record of 2 million retweets before midnight the same night. That record was previously set by President Barack Obama, hugging first lady Michelle Obama after his 2012 re-election.

The selfie caused Twitter to crash for more than 20 minutes, also breaking the record for the longest crash of the social media site. Twitter was infamous for crashing in its early days (anyone remember "Fail Whale?"), so it's no wonder the social media giant worked extra hard to completely prepare their website infrastructure before going public in November 2013. This included building their own load testing tool, Iago, in 2012.

If they built their own tool to perform their own load test, why did the selfie cause their site to crash? The Oscar selfie crash is a perfect example of what companies can easily overlook. Twitter did not test their users properly and their homegrown tool clearly doesn't solve all of their problems... their servers still crash.

What is Iago and why did Twitter decide to make it? And what does that have to do with your decision to use homegrown tools versus vendor load testing tools? Don't worry, we will tell you.

Twitter's Homegrown Load Testing Tool: Iago
Iago was created in June of 2012 by Twitter's internal engineering team. According to Twitter, Iago is a load generator created to help the social media site test services before they encounter production traffic. Chris Aniszczyk, Head of Open Source at Twitter, said, "There are many load generators available in the open source and commercial software worlds, but Iago provided us with capabilities that are uniquely suited for Twitter's environment and the precise degree to which we need to test our services."

Basically their homegrown tool was completely customized for their platform alone - a very attractive aspect of developing your own tool.

The three attributes Twitter focused on in creating Iago were:

  1. High performance: Iago was designed to generate traffic in a precise and predictable way, to minimize variance between test runs and allow comparisons to be made between development iterations.
  2. Multi-protocol: Modeling a system as complex as Twitter can be difficult, but it's made easier by decomposing it into component services. Once decomposed, each piece can be tested in isolation; which requires the load generator to speak each service's protocol. Twitter has in excess of 100 such services, and Iago tests most of them using built-in support for the internal protocols Twitter uses.
  3. Extensible: Iago is designed for engineers. It assumes the person building the system will also be interested in validating performance. As such, the tool is designed from the ground up to be extensible - making it easy to generate new traffic types, over new protocols and with individualized traffic sources.

Why Twitter Couldn't Handle Ellen's Selfie
If we were to do the math, Iago was up and running for nearly two years before the Oscar selfie. What happened to their load testing tool?

There were two main reasons why Twitter crashed. First, the tweet Ellen posted was a picture. On Twitter, a tweet accounts for only 260 bytes of data while a picture on Twitter accounts for 33KB of data, almost 130 times as much as a tweet. Second, Twitter's distributed server system was already at max capacity so the load taken on by the website couldn't be distributed to any nearby servers.

Twitter made one major mistake contributing to the crash back in March: they didn't anticipate and replicate real user activity. Most likely Iago wasn't instructed to generate a load based on a picture being retweeted millions of times, thus Twitter didn't know what to expect when the Oscars rolled around.

Homegrown Tool vs. Vendor Load Testing Solutions
Twitter was looking for a DIY homegrown solution because of their unique platform, and while most load testing tools seek to accomplish the same goal, there are always differences between tools. Here are some of the differences we see between homegrown and vendor-provided load testing tools.

Homegrown

Vendor

1. You can customize it - A homegrown tool, created completely from scratch, means you can build exactly what you think you need. But you don't get the benefit of lots of other people's experiences - so what you think you need may not turn out to be what you actually need.

2. Homegrown tools are free like a puppy is free - We have mentioned this analogy before in another post, and it needs to be brought up again. Homegrown tools aren't really free. You have to pay a team to keep them up and running.

3. What if someone leaves? - A couple of developers are experts on the tool they built, but what happens when they leave? Who is going to be your expert? If the new person isn't properly trained and if the code isn't well documented, then modifications to the code become extremely difficult.

1. Your vendor makes it extensible - A vendor that supports lots of users is constantly adding features and capabilities to support needs you may not have realized you have yet. With extensible APIs and SDKs, you still have the ability to add integrations and the protocol support your application demands.

2. You pay for something that works - With homegrown tools there is no guarantee that it will work 100% of the time. By paying a vendor to use their tool, you have assurances that your load testing tool won't let you down when you need it most.

3. Support Team - Vendors dedicate people to work on any issues and keep you worry-free. Their team of experts is available to make sure all of your questions and concerns are addressed.

Homegrown Tools Are Not for Everyone
Twitter's tool has done well to help them improve the performance of the service, but continued service disruptions show that it isn't perfect. A homegrown tool isn't always the best solution, and most of the time, companies do not have the resources handy to completely build their load testing tool from scratch. If you are interested in learning more about vendor options, give us a call. We're more than happy to help.

More Stories By Tim Hinds

Tim Hinds is the Product Marketing Manager for NeoLoad at Neotys. He has a background in Agile software development, Scrum, Kanban, Continuous Integration, Continuous Delivery, and Continuous Testing practices.

Previously, Tim was Product Marketing Manager at AccuRev, a company acquired by Micro Focus, where he worked with software configuration management, issue tracking, Agile project management, continuous integration, workflow automation, and distributed version control systems.

Comments (0)

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


Cloud Expo Breaking News
Cloud Computing is evolving into a Big Three of Amazon Web Services, Google Cloud, and Microsoft Azure. Cloud 360: Multi-Cloud Bootcamp, being held Nov 4–5, 2014, in conjunction with 15th Cloud Expo in Santa Clara, CA, delivers a real-world demonstration of how to deploy and configure a scalable and available web application on all three platforms. The Cloud 360 Bootcamp, led by Janakiram MSV, an analyst with Gigaom Research, is the first bootcamp that introduces the core concepts of Infrastructure as a Service (IaaS) based on the workings of the Big Three platforms – Amazon EC2, Google Compute Engine, and Azure VMs. Bootcamp attendees will get to see the big picture and also receive the knowledge needed to make the best cloud decisions for their business applications and entire enterprise IT organization.
Scott Jenson leads a project called The Physical Web within the Chrome team at Google. Project members are working to take the scalability and openness of the web and use it to talk to the exponentially exploding range of smart devices. Nearly every company today working on the IoT comes up with the same basic solution: use my server and you'll be fine. But if we really believe there will be trillions of these devices, that just can't scale. We need a system that is open a scalable and by using the URL as a basic building block, we open this up and get the same resilience that the web enjoys.
The Internet of Things is a natural complement to the cloud and related technologies such as Big Data, analytics, and mobility. In his session at Internet of @ThingsExpo, Joe Weinman will lay out four generic strategies – digital disciplines – to exploit emerging digital technologies for strategic advantage. Joe Weinman has held executive leadership positions at Bell Labs, AT&T, Hewlett-Packard, and Telx, in areas such as corporate strategy, business development, product management, operations, and R&D.
SYS-CON Events announced today that DevOps.com has been named “Media Sponsor” of SYS-CON's “DevOps Summit at Cloud Expo,” which will take place on June 10–12, 2014, at the Javits Center in New York City, New York. DevOps.com is where the world meets DevOps. It is the largest collection of original content relating to DevOps on the web today Featuring up-to-the-minute news, feature stories, blogs, bylined articles and more, DevOps.com is where the thought leaders of the DevOps movement make their ideas known.
There are 182 billion emails sent every day, generating a lot of data about how recipients and ISPs respond. Many marketers take a more-is-better approach to stats, preferring to have the ability to slice and dice their email lists based numerous arbitrary stats. However, fundamentally what really matters is whether or not sending an email to a particular recipient will generate value. Data Scientists can design high-level insights such as engagement prediction models and content clusters that allow marketers to cut through the noise and design their campaigns around strong, predictive signals, rather than arbitrary statistics. SendGrid sends up to half a billion emails a day for customers such as Pinterest and GitHub. All this email adds up to more text than produced in the entire twitterverse. We track events like clicks, opens and deliveries to help improve deliverability for our customers – adding up to over 50 billion useful events every month. While SendGrid data covers only abo...
SYS-CON Events announced today that the Web Host Industry Review has been named “Media Sponsor” of SYS-CON's 15th International Cloud Expo®, which will take place on November 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. Since 2000, The Web Host Industry Review has made a name for itself as the foremost authority of the Web hosting industry providing reliable, insightful and comprehensive news, reviews and resources to the hosting community. TheWHIR Blogs provides a community of expert industry perspectives. The Web Host Industry Review Magazine also offers a business-minded, issue-driven perspective of interest to executives and decision-makers. WHIR TV offers on demand web hosting video interviews and web hosting video features of the key persons and events of the web hosting industry. WHIR Events brings together like-minded hosting industry professionals and decision-makers in local communities. TheWHIR is an iNET Interactive property.
SYS-CON Events announced today that O'Reilly Media has been named “Media Sponsor” of SYS-CON's 15th International Cloud Expo®, which will take place on November 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. O'Reilly Media spreads the knowledge of innovators through its books, online services, magazines, and conferences. Since 1978, O'Reilly Media has been a chronicler and catalyst of cutting-edge development, homing in on the technology trends that really matter and spurring their adoption by amplifying "faint signals" from the alpha geeks who are creating the future. An active participant in the technology community, the company has a long history of advocacy, meme-making, and evangelism.
SYS-CON Events announced today that Verizon has been named “Gold Sponsor” of SYS-CON's 15th International Cloud Expo®, which will take place on November 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. Verizon Enterprise Solutions creates global connections that generate growth, drive business innovation and move society forward. With industry-specific solutions and a full range of global wholesale offerings provided over the company's secure mobility, cloud, strategic networking and advanced communications platforms, Verizon Enterprise Solutions helps open new opportunities around the world for innovation, investment and business transformation. Visit verizonenterprise.com to learn more.
SYS-CON Events announced today that TMCnet has been named “Media Sponsor” of SYS-CON's 15th International Cloud Expo®, which will take place on November 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA. Technology Marketing Corporation (TMC) is the world's leading business to business and integrated marketing media company, servicing niche markets within the communications and technology industries.
"In my session I spoke about enterprise cloud analytics and how we can leverage analytics as a service," explained Ajay Budhraja, CTO at the Department of Justice, in this SYS-CON.tv interview at the 14th International Cloud Expo®, held June 10-12, 2014, at the Javits Center in New York City. Cloud Expo® 2014 Silicon Valley, November 4–6, at the Santa Clara Convention Center in Santa Clara, CA, will feature technical sessions from a rock star conference faculty and the leading Cloud industry players in the world.
“We are starting to see people move beyond the commodity cloud and enterprises need to start focusing on additional value added services in order to really drive their adoption," explained Jason Mondanaro, Director of Product Management at MetraTech, in this SYS-CON.tv interview at the 14th International Cloud Expo®, held June 10-12, 2014, at the Javits Center in New York City. Cloud Expo® 2014 Silicon Valley, November 4–6, at the Santa Clara Convention Center in Santa Clara, CA, will feature technical sessions from a rock star conference faculty and the leading Cloud industry players in the world.
"We are automated capacity control software, which basically looks at all the supply and demand and running a virtual cloud environment and does a deep analysis of that and says where should things go," explained Andrew Hillier, Co-founder & CTO of CiRBA, in this SYS-CON.tv interview at the 14th International Cloud Expo®, held June 10-12, 2014, at the Javits Center in New York City. Cloud Expo® 2014 Silicon Valley, November 4–6, at the Santa Clara Convention Center in Santa Clara, CA, will feature technical sessions from a rock star conference faculty and the leading Cloud industry players in the world.
Almost everyone sees the potential of Internet of Things but how can businesses truly unlock that potential. The key will be in the ability to discover business insight in the midst of an ocean of Big Data generated from billions of embedded devices via Systems of Discover. Businesses will also need to ensure that they can sustain that insight by leveraging the cloud for global reach, scale and elasticity. In his session at Internet of @ThingsExpo, Mac Devine, Distinguished Engineer at IBM, will discuss bringing these three elements together via Systems of Discover.
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 15th Internet of @ThingsExpo, Chad Jones, Vice President, Product Strategy of LogMeIn's Xively IoT Platform, will show you how to approach creating broadly successful connected customer solutions using real world business transformation studies including New England BioLabs and more.
All too many discussions about DevOps conclude that the solution is an all-purpose player: developer and operations guru, complete with pager for round-the-clock duty. For most organizations that is not the way forward. In his session at DevOps Summit, Bernard Golden, Vice President of Strategy at ActiveState, will discuss how to achieve the agility and speed of end-to-end automation without requiring an organization stocked with Supermen and Superwomen.