Welcome!

Agile Computing Authors: Liz McMillan, SmartBear Blog, James Carlini, Ferhat Hatay, Charlotte Spencer-Smith

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.


@ThingsExpo Stories
Join us at Cloud Expo | @ThingsExpo 2016 – June 7-9 at the Javits Center in New York City and November 1-3 at the Santa Clara Convention Center in Santa Clara, CA – and deliver your unique message in a way that is striking and unforgettable by taking advantage of SYS-CON's unmatched high-impact, result-driven event / media packages.
As enterprises work to take advantage of Big Data technologies, they frequently become distracted by product-level decisions. In most new Big Data builds this approach is completely counter-productive: it presupposes tools that may not be a fit for development teams, forces IT to take on the burden of evaluating and maintaining unfamiliar technology, and represents a major up-front expense. In his session at @BigDataExpo at @ThingsExpo, Andrew Warfield, CTO and Co-Founder of Coho Data, will dis...
Silver Spring Networks, Inc. (NYSE: SSNI) extended its Internet of Things technology platform with performance enhancements to Gen5 – its fifth generation critical infrastructure networking platform. Already delivering nearly 23 million devices on five continents as one of the leading networking providers in the market, Silver Spring announced it is doubling the maximum speed of its Gen5 network to up to 2.4 Mbps, increasing computational performance by 10x, supporting simultaneous mesh communic...
Eighty percent of a data scientist’s time is spent gathering and cleaning up data, and 80% of all data is unstructured and almost never analyzed. Cognitive computing, in combination with Big Data, is changing the equation by creating data reservoirs and using natural language processing to enable analysis of unstructured data sources. This is impacting every aspect of the analytics profession from how data is mined (and by whom) to how it is delivered. This is not some futuristic vision: it's ha...
The cloud promises new levels of agility and cost-savings for Big Data, data warehousing and analytics. But it’s challenging to understand all the options – from IaaS and PaaS to newer services like HaaS (Hadoop as a Service) and BDaaS (Big Data as a Service). In her session at @BigDataExpo at @ThingsExpo, Hannah Smalltree, a director at Cazena, will provide an educational overview of emerging “as-a-service” options for Big Data in the cloud. This is critical background for IT and data profes...
One of the bewildering things about DevOps is integrating the massive toolchain including the dozens of new tools that seem to crop up every year. Part of DevOps is Continuous Delivery and having a complex toolchain can add additional integration and setup to your developer environment. In his session at @DevOpsSummit at 18th Cloud Expo, Miko Matsumura, Chief Marketing Officer of Gradle Inc., will discuss which tools to use in a developer stack, how to provision the toolchain to minimize onboa...
Companies can harness IoT and predictive analytics to sustain business continuity; predict and manage site performance during emergencies; minimize expensive reactive maintenance; and forecast equipment and maintenance budgets and expenditures. Providing cost-effective, uninterrupted service is challenging, particularly for organizations with geographically dispersed operations.
SYS-CON Events announced today that Interoute, owner-operator of one of Europe's largest networks and a global cloud services platform, has been named “Bronze Sponsor” of SYS-CON's 18th Cloud Expo, which will take place on June 7-9, 2015 at the Javits Center in New York, New York. Interoute is the owner-operator of one of Europe's largest networks and a global cloud services platform which encompasses 12 data centers, 14 virtual data centers and 31 colocation centers, with connections to 195 ad...
SYS-CON Events announced today that Commvault, a global leader in enterprise data protection and information management, has been named “Bronze 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, and the 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. Commvault is a leading provider of data protection and information management...
There will be new vendors providing applications, middleware, and connected devices to support the thriving IoT ecosystem. This essentially means that electronic device manufacturers will also be in the software business. Many will be new to building embedded software or robust software. This creates an increased importance on software quality, particularly within the Industrial Internet of Things where business-critical applications are becoming dependent on products controlled by software. Qua...
With an estimated 50 billion devices connected to the Internet by 2020, several industries will begin to expand their capabilities for retaining end point data at the edge to better utilize the range of data types and sheer volume of M2M data generated by the Internet of Things. In his session at @ThingsExpo, Don DeLoach, CEO and President of Infobright, will discuss the infrastructures businesses will need to implement to handle this explosion of data by providing specific use cases for filte...
SYS-CON Events announced today that Avere Systems, a leading provider of enterprise storage for the hybrid cloud, 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. Avere delivers a more modern architectural approach to storage that doesn’t require the overprovisioning of storage capacity to achieve performance, overspending on expensive storage media for inactive data or the overbuilding of data centers ...
SYS-CON Events announced today that Pythian, a global IT services company specializing in helping companies adopt disruptive technologies to optimize revenue-generating systems, has been named “Bronze Sponsor” of SYS-CON's 18th Cloud Expo, which will take place on June 7-9, 2015 at the Javits Center in New York, New York. Founded in 1997, Pythian is a global IT services company that helps companies compete by adopting disruptive technologies such as cloud, Big Data, advanced analytics, and DevO...
SYS-CON Events announced today that Alert Logic, Inc., the leading provider of Security-as-a-Service solutions for the cloud, 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. Alert Logic, Inc., provides Security-as-a-Service for on-premises, cloud, and hybrid infrastructures, delivering deep security insight and continuous protection for customers at a lower cost than traditional security solutions. Ful...
Fortunately, meaningful and tangible business cases for IoT are plentiful in a broad array of industries and vertical markets. These range from simple warranty cost reduction for capital intensive assets, to minimizing downtime for vital business tools, to creating feedback loops improving product design, to improving and enhancing enterprise customer experiences. All of these business cases, which will be briefly explored in this session, hinge on cost effectively extracting relevant data from ...
SYS-CON Events announced today that iDevices®, the preeminent brand in the connected home industry, 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. iDevices, the preeminent brand in the connected home industry, has a growing line of HomeKit-enabled products available at the largest retailers worldwide. Through the “Designed with iDevices” co-development program and its custom-built IoT Cloud Infrastruc...
The Quantified Economy represents the total global addressable market (TAM) for IoT that, according to a recent IDC report, will grow to an unprecedented $1.3 trillion by 2019. With this the third wave of the Internet-global proliferation of connected devices, appliances and sensors is poised to take off in 2016. In his session at @ThingsExpo, David McLauchlan, CEO and co-founder of Buddy Platform, will discuss how the ability to access and analyze the massive volume of streaming data from mil...
WebSocket is effectively a persistent and fat pipe that is compatible with a standard web infrastructure; a "TCP for the Web." If you think of WebSocket in this light, there are other more hugely interesting applications of WebSocket than just simply sending data to a browser. In his session at 18th Cloud Expo, Frank Greco, Director of Technology for Kaazing Corporation, will compare other modern web connectivity methods such as HTTP/2, HTTP Streaming, Server-Sent Events and new W3C event APIs ...
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,...
With the Apple Watch making its way onto wrists all over the world, it’s only a matter of time before it becomes a staple in the workplace. In fact, Forrester reported that 68 percent of technology and business decision-makers characterize wearables as a top priority for 2015. Recognizing their business value early on, FinancialForce.com was the first to bring ERP to wearables, helping streamline communication across front and back office functions. In his session at @ThingsExpo, Kevin Roberts...