Black Friday Load Testing Lessons to Learn for Free Shipping Day 2014
Will Free Shipping Day be bigger than Black Friday?
December 15, 2014

Alon Girmonsky
BlazeMeter

Share this

Black Friday may be behind us for another year, but Free Shipping Day is just around the corner.

On the 18th of December, nearly 1,000 online stores will offer free shipping for last minute holiday shoppers.

If you're one of these 1,000 retailers, no doubt you're rigorously stress testing your sites and apps to ensure they will run smoothly on the big day.

But is your testing enough to guarantee a smooth shopping day for your customers? Huge retailers like Best Buy, Tesco, Argos, John Lewis and Currys all had costly crashes on Black Friday 2014, despite extensive preparations and testing. On top of that, Free Shipping Day is likely to bring new, specific challenges for your site — and it's getting bigger every year.

Will Free Shipping Day be bigger than Black Friday? 2014 marks the 7th year for Free Shipping Day, and each year is bigger than the last. Since 2012, spending on Free Shipping Day has exceeded $1 billion and it has overtaken Black Friday's online spending for two years in a row. In fact, just two years after it was created, Free Shipping Day made its mark as the third heaviest day for online shopping in US history.

So there's a good chance that your website will be under even more stress this Thursday than Black Friday. The good news is that you can learn from mistakes made by others to ensure your website will be able to handle the load. Here are three lessons that we can learn this year:

Lesson #1. Don't Underestimate the Load

Both Tesco and Best Buy underestimated the huge surge of traffic that came to their sites on Black Friday. Tesco reported having five times more customers than 2013 and Best Buy witnessed "record levels of website traffic".

There are many reasons why traffic might be higher than you expected, such as the rising popularity of Free Shipping Day, the increasingly widespread use of online shopping and even the fact that you might be getting traffic from your competitors if their websites are down.

That's why it is important to try to bring your system into failure when running your load testing. Whether your failure will be caused by CPU, memory, connection pools, a network band issue or something else, you need to find it. I recommend running a sequence of tests while continually increasing the load and monitoring your hits/s throughput as you do this. Keep on doing this until you hit a scaling problem.

For example: the chart below shows where your system reaches its capacity (in this case after 300 virtual users).


Lesson #2: Recover Quickly from Technical Problems

On Black Friday, Tesco's website was down for 12 hours – half of the busiest shopping day of the year.

Every minute that your website is down, you're losing hundreds of thousands of dollars in lost revenue. So, whether a crash is caused by high traffic loads or a power outage, it's vital to put plans in place to ensure you'll recover quickly.

I recommend ensuring you have back-up servers and locations ready so you can recover quickly if there's a problem. Set up a database replication, database failover cluster or application failover cluster. If there's a problem, just switch over to the failover location. You won't have to wait for your main server to recover as your backup can be running while you resolve the critical issues.

Lesson #3: Run Load Tests from Different Devices in the Production Environment

Shortly after Best Buy's Black Friday crash, a company spokesman gave the following statement: "A concentrated spike in mobile traffic triggered issues that led us to shut down BestBuy.com in order to take proactive measures to restore full performance.”

Your traffic load won't come in equal measures from all devices – or locations for that matter. The vast majority of your traffic might come from one type of device and one specific region. That's why it's crucial to run your tests in different geo-locations and from different devices on your live production site. This is the best way to ensure that your testing is accurate, that your test plan is well organized and that you're stressing every point in the entire chain of delivery. I recommend testing in your production environment at a time when traffic is very low (such as 3am on a Sunday morning) and informing your customers that there may be some downtime during these hours.

There are various ways that you can run such tests. You can use an open source load testing tool and buy several Virtual Private Servers (VPS) in different geo-locations to test your web or app servers under heavy load from various geographical locations. Alternatively, you can use cloud performance testing tools to simulate the load from various devices and multiple geo-locations.

Specific Challenges of Free Shipping Day

In addition to learning from all of the above mistakes, it's also important to address the specific challenges that Free Shipping Day will bring.

For 24 hours only, developers need to ensure that the checkout tallies won't include shipping costs. Some companies will have a flexible framework in place that enables them to just click a checkbox to exclude shipping fees. However, most companies won't have such a framework in place. Instead, they will have software that needs adapting. In such cases, many developers will make ad-hoc changes to a few lines of code to remove the shipping fees for these key 24 hours.

However, this type of “quick fix” can lead to technical glitches or even incorrect pricing calculations. If the fix isn't implemented correctly or the developers fail to update every page that includes the shipping fees, your customers may see additional costs on pages that you overlooked.

In addition to these functional issues, all of the code changes might lead to unforeseen problems with the performance of your website or app.

To avoid such issues, it is critical to avoid making changes to the code at the last minute. You need to ensure that you have enough time and the right environment to check the repercussions of any changes that are made.

Once the changes have been made, take the time to check the functionality in the staging or QA environment. It's worth asking your QA team to ensure that it is operating as anticipated. Once the change has been verified from a functional perspective, then you need to check that it works on a high scale. To do this, it's best to run a load test in the production environment around four to five hours before Free Shipping Day officially begins. This will give you enough time to make any last minute fixes that you need before your customers start flooding your site.

If you take all of these considerations into account, I'm confident that Free Shipping Day 2014 will be successful and profitable for you and your company.

Alon Girmonsky is Founder and CEO of BlazeMeter.

Share this

The Latest

March 21, 2019

Achieving audit compliance within your IT ecosystem can be an iterative process, and it doesn't have to be compressed into the five days before the audit is due. Following is a four-step process I use to guide clients through the process of preparing for and successfully completing IT audits ...

March 20, 2019

Network performance issues come in all shapes and sizes, and can require vast amounts of time and resources to solve. Here are three examples of painful network performance issues you're likely to encounter this year, and how NPMD solutions can help you overcome them ...

March 19, 2019

"Scale up" versus "scale out" doesn't just apply to hardware investments, it also has an impact on product features. "Scale up" promotes buying the feature set you think you need now, then adding "feature modules" and licenses as you discover additional feature requirements are needed. Often as networks grow in size they also grow in complexity ...

March 18, 2019

Network Packet Brokers play a critical role in gaining visibility into new complex networks. They deliver the packet data and information IT and security teams need to identify problems, recognize security issues, and ensure overall network performance. However, not all Packet Brokers are created equal when it comes to scalability. Simply "scaling up" your network infrastructure at every growth point is a more complex and more expensive endeavor over time. Let's explore three ways the "scale up" approach to infrastructure growth impedes NetOps and security professionals (and the business as a whole) ...

March 15, 2019

Loyal users are the key to your service desk's success. Happy users want to use your services and they recommend your services in the organization. It takes time and effort to exceed user expectations, but doing so means keeping the promises we make to our users and being careful not to do too much without careful consideration for what's best for the organization and users ...

March 14, 2019

What's the difference between user satisfaction and user loyalty? How can you measure whether your users are satisfied and will keep buying from you? How much effort should you make to offer your users the ultimate experience? If you're a service provider, what matters in the end is whether users will keep coming back to you and will stay loyal ...

March 13, 2019

What if I said that a 95% reduction in the amount of IT noise, 99% reduction in ticket volume and 99% L1 resolution rate are not only possible, but that some of the largest, most complex enterprises in the world see these metrics in their environments every day, thanks to Artificial Intelligence (AI) and Machine Learning (ML)? Would you dismiss that as belonging to the realm of science fiction? ...

March 12, 2019
As a consumer, when you order products online, how do you expect them to get delivered? Some key requirements are: the product must arrive on time, well-packed, and ultimately must give you an easy gateway to return it if it is not as per your expectations. All this has been made possible via a single application. But what if this application doesn't function the way you want or cracks down mid-way, or probably leaks off information about you to some potential hackers? Technical uncertainty and digital chaos are the two double-edged swords dangling over this billion-dollar ecommerce market. Can Quality Assurance and Software Testing save application developers from this endless juggle? ...
March 11, 2019

Of those surveyed, 96% of organizations have a digital transformation strategy, with 57% approaching it as an enterprise-wide priority, with a clear emphasis on speed of business, costs, risk, and customer satisfaction, according to IDC’s Aligning IT Strategies and Business Expectations for Digital Transformation Success, sponsored by EasyVista ...

March 08, 2019

One of my ongoing areas of focus is analytics, AIOps, and the intersection with AI and machine learning more broadly. Within this space, sad to say, semantic confusion surrounding just what these terms mean echoes the confusions surrounding ITSM ...