Welcome!

Microservices Expo Authors: Robert Reeves, Elizabeth White, Flint Brenton, Anders Wallgren, Pat Romanski

Related Topics: Microservices Expo, Java IoT, Linux Containers, Agile Computing, Cloud Security, @BigDataExpo

Microservices Expo: 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.


@MicroservicesExpo Stories
In 2006, Martin Fowler posted his now famous essay on Continuous Integration. Looking back, what seemed revolutionary, radical or just plain crazy is now common, pedestrian and "just what you do." I love it. Back then, building and releasing software was a real pain. Integration was something you did at the end, after code complete, and we didn't know how long it would take. Some people may recall how we, as an industry, spent a massive amount of time integrating code from one team with another...
As the software delivery industry continues to evolve and mature, the challenge of managing the growing list of the tools and processes becomes more daunting every day. Today, Application Lifecycle Management (ALM) platforms are proving most valuable by providing the governance, management and coordination for every stage of development, deployment and release. Recently, I spoke with Madison Moore at SD Times about the changing market and where ALM is headed.
Struggling to keep up with increasing application demand? Learn how Platform as a Service (PaaS) can streamline application development processes and make resource management easy.
If there is anything we have learned by now, is that every business paves their own unique path for releasing software- every pipeline, implementation and practices are a bit different, and DevOps comes in all shapes and sizes. Software delivery practices are often comprised of set of several complementing (or even competing) methodologies – such as leveraging Agile, DevOps and even a mix of ITIL, to create the combination that’s most suitable for your organization and that maximize your busines...
SYS-CON Events announced today that Peak 10, Inc., a national IT infrastructure and cloud services provider, will exhibit at SYS-CON's 18th International Cloud Expo®, which will take place on June 7-9, 2016, at the Javits Center in New York City, NY. Peak 10 provides reliable, tailored data center and network services, cloud and managed services. Its solutions are designed to scale and adapt to customers’ changing business needs, enabling them to lower costs, improve performance and focus inter...
The goal of any tech business worth its salt is to provide the best product or service to its clients in the most efficient and cost-effective way possible. This is just as true in the development of software products as it is in other product design services. Microservices, an app architecture style that leans mostly on independent, self-contained programs, are quickly becoming the new norm, so to speak. With this change comes a declining reliance on older SOAs like COBRA, a push toward more s...
From the conception of Docker containers to the unfolding microservices revolution we see today, here is a brief history of what I like to call 'containerology'. In 2013, we were solidly in the monolithic application era. I had noticed that a growing amount of effort was going into deploying and configuring applications. As applications had grown in complexity and interdependency over the years, the effort to install and configure them was becoming significant. But the road did not end with a ...
You deployed your app with the Bluemix PaaS and it's gaining some serious traction, so it's time to make some tweaks. Did you design your application in a way that it can scale in the cloud? Were you even thinking about the cloud when you built the app? If not, chances are your app is going to break. Check out this webcast to learn various techniques for designing applications that will scale successfully in Bluemix, for the confidence you need to take your apps to the next level and beyond.
Digital means customer preferences and behavior are driving enterprise technology decisions to be sure, but let’s not forget our employees. After all, when we say customer, we mean customer writ large, including partners, supply chain participants, and yes, those salaried denizens whose daily labor forms the cornerstone of the enterprise. While your customers bask in the warm rays of your digital efforts, are your employees toiling away in the dark recesses of your enterprise, pecking data into...
SYS-CON Events announced today that DatacenterDynamics has been named “Media Sponsor” of SYS-CON's 18th International Cloud Expo, which will take place on June 7–9, 2016, at the Javits Center in New York City, NY. DatacenterDynamics is a brand of DCD Group, a global B2B media and publishing company that develops products to help senior professionals in the world's most ICT dependent organizations make risk-based infrastructure and capacity decisions.
Wow, if you ever wanted to learn about Rugged DevOps (some call it DevSecOps), sit down for a spell with Shannon Lietz, Ian Allison and Scott Kennedy from Intuit. We discussed a number of important topics including internal war games, culture hacking, gamification of Rugged DevOps and starting as a small team. There are 100 gold nuggets in this conversation for novices and experts alike.
With DevOps becoming more well-known and established practice in nearly every industry that delivers software, it is important to continually reassess its efficacy. This week’s top 10 includes a discussion on how the quick uptake of DevOps adoption in the enterprise has posed some serious challenges. Additionally, organizations who have taken the DevOps plunge must find ways to find, hire and keep their DevOps talent in order to keep the machine running smoothly.
Call it DevOps or not, if you are concerned about releasing more code faster and at a higher quality, the resulting software delivery chain and process will look and smell like DevOps. But for existing development teams, no matter what the velocity objective is, getting from here to there is not something that can be done without a plan. Moving your release cadence from months to weeks is not just about learning Agile practices and getting some automation tools. It involves people, tooling and ...
Between the mockups and specs produced by analysts, and resulting applications built by developers, there exists a gulf where projects fail, costs spiral, and applications disappoint. Methodologies like Agile attempt to address this with intensified communication, with partial success but many limitations. In his session at 18th Cloud Expo, Charles Kendrick, CTO & Chief Architect at Isomorphic Software, will present a revolutionary model enabled by new technologies. Learn how business and devel...
The notion of customer journeys, of course, are central to the digital marketer’s playbook. Clearly, enterprises should focus their digital efforts on such journeys, as they represent customer interactions over time. But making customer journeys the centerpiece of the enterprise architecture, however, leaves more questions than answers. The challenge arises when EAs consider the context of the customer journey in the overall architecture as well as the architectural elements that make up each...
SYS-CON Events announced today that Stratoscale, the software company developing the next generation data center operating system, will exhibit at SYS-CON's 18th International Cloud Expo®, which will take place on June 7-9, 2016, at the Javits Center in New York City, NY. Stratoscale is revolutionizing the data center with a zero-to-cloud-in-minutes solution. With Stratoscale’s hardware-agnostic, Software Defined Data Center (SDDC) solution to store everything, run anything and scale everywhere...
SYS-CON Events announced today that Men & Mice, the leading global provider of DNS, DHCP and IP address management overlay solutions, will exhibit at SYS-CON's 18th International Cloud Expo®, which will take place on June 7-9, 2016, at the Javits Center in New York City, NY. The Men & Mice Suite overlay solution is already known for its powerful application in heterogeneous operating environments, enabling enterprises to scale without fuss. Building on a solid range of diverse platform support,...
Much of the discussion around cloud DevOps focuses on the speed with which companies need to get new code into production. This focus is important – because in an increasingly digital marketplace, new code enables new value propositions. New code is also often essential for maintaining competitive parity with market innovators. But new code doesn’t just have to deliver the functionality the business requires. It also has to behave well because the behavior of code in the cloud affects performan...
This is not a small hotel event. It is also not a big vendor party where politicians and entertainers are more important than real content. This is Cloud Expo, the world's longest-running conference and exhibition focused on Cloud Computing and all that it entails. If you want serious presentations and valuable insight about Cloud Computing for three straight days, then register now for Cloud Expo.
I had the opportunity to catch up with Chris Corriere - DevOps Engineer at AutoTrader - to talk about his experiences in the realm of Rugged DevOps. We discussed automation, culture and collaboration, and which thought leaders he is following. Chris Corriere: Hey, I'm Chris Corriere. I'm a DevOps Engineer AutoTrader. Derek Weeks: Today we're going to talk about Rugged DevOps. It's a subject that's gaining a lot of traction in the community but not a lot of people are really familiar with wh...