Incident · Mid
Ticketmaster/Taylor Swift 2022: 3.5 billion requests, 4x the previous peak
Real incident. Key points: overload control and reservations and concurrency.
Short answer
Real incident. Key points: overload control and reservations and concurrency. The ticket sale for Taylor Swift's Eras tour used Verified Fan, a pre-registration that Ticketmaster describes as designed to identify real people and keep bots away. More than 3.5 million people registered and about 1.5 million received codes to enter the sale.
01 · CONTEXT
A sale with pre-registration, code, and queue
The ticket sale for Taylor Swift's Eras tour used Verified Fan, a pre-registration that Ticketmaster describes as designed to identify real people and keep bots away. More than 3.5 million people registered and about 1.5 million received codes to enter the sale. Historically, according to the company, about 40% of invitees show up and buy.
The company itself calls the predictability and the confiabilidade hallmarks of Verified Fan, and describes pre-registration as a way to help manage high-demand shows.
The fan logs in. Verification is tied to the account and is checked at that moment.
Only verified people can enter the purchase queue.
To complete the purchase, the buyer must also enter the unique code.
With the code validated, the purchase service records the sale in inventory (illustrative step).
02 · THE PEAK
Registered, invited, and requests: different magnitudes
Ticketmaster attributes the unprecedented traffic to the sum of bot attacks and fans without codes, and reports 3.5 billion total requests to the system, four times the previous peak. Live Nation chairman Greg Maffei said the site was supposed to open to 1.5 million verified fans and that 14 million people, bots included, accessed it.
| Number | What it measures | Who reported it |
|---|---|---|
| 3.5 million | People pre-registered on Verified Fan | Ticketmaster |
| 1.5 million | People who received codes for the sale | Ticketmaster |
| 14 million | People who accessed the site, bots included | Greg Maffei, of Live Nation |
| 3.5 billion | Total requests to the system, four times the previous peak | Ticketmaster |
03 · DEGRADATION
Slowing down to keep the system standing
Those who were not verified did not enter the queue, but the overall volume on the site forced the company to slow down the queues to keep them stable. According to the company, a stadium sale usually takes about an hour; this time some sales were slowed and others postponed, at the cost of longer waits for some fans.
The company estimates that about 15% of interactions on the site had problems, including code validation errors that made fans lose tickets that were already in their cart.
Besides verified fans, bots and visitors without codes generated unprecedented traffic: 3.5 billion total requests, four times the previous peak.
Those who were not verified could not enter the queue.
Even so, the overall volume on the site forced the queues to be slowed to keep them stable, with longer waits for some fans.
Code validation errors made some fans lose tickets that were already in their cart.
With demand above the remaining inventory, the next public sale was canceled.
Even so, more than 2 million tickets were sold on November 15. On the eve of the public sale, Ticketmaster announced its cancellation, citing extraordinary demand on its systems and insufficient remaining inventory.
04 · THE TESTIMONY
What the company told the Senate
Joe Berchtold, president and chief financial officer of Live Nation, testified before the US Senate Judiciary Committee. According to reports, he said bot traffic was three times larger than the company had ever experienced and that, for the first time, bots went after the Verified Fan system. He stated that the bots did not penetrate the systems or acquire tickets, but that the attack forced the company to slow down and even pause sales.
According to CFO Dive, the written testimony said the company could improve by staggering sales over a longer period and setting fans' expectations for obtaining tickets.
05 · LESSONS
What the design needs to anticipate
Admission before inventory: when demand can exceed capacity by an order of magnitude, deciding who gets in before touching inventory protects the critical path. A waiting room, account verification, and a per-buyer code are layers of that decision, and a waiting queue only helps if the exit rate respects what the purchase can handle.
Size for the traffic, not for the guest list: bots and visitors without a code also consume capacity, even though they cannot buy. That is why sizing and load tests must start from the worst plausible traffic, not from the number of invitees, and the escalabilidade at the edge counts as much as the one on inventory.
Steps on the critical path must tolerate retries: if a validation fails under load, the legitimate buyer tries again, and the operation must be idempotente and must not discard the cart. The design of seat reservation with locking and expiry is in the classic ticket-office case; this case covers what comes before it.
Frequently asked questions
What is Ticketmaster/Taylor Swift 2022: 3.5 billion requests, 4x the previous peak?
Real incident. Key points: overload control and reservations and concurrency.
What does the Ticketmaster/Taylor Swift 2022: 3.5 billion requests, 4x the previous peak design cover?
It is organized in these sections: A sale with pre-registration, code, and queue, Registered, invited, and requests: different magnitudes, Slowing down to keep the system standing, What the company told the Senate, and What the design needs to anticipate.
How long is Ticketmaster/Taylor Swift 2022: 3.5 billion requests, 4x the previous peak and what level is it?
It takes about 12 minutes to read and is rated Mid level.
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