CASE STUDY: QUIZLET
At a Glance
For Online Learning Innovator Quizlet,
Academic Performance and Web
Performance Go Hand in Hand
Quizlet is among the largest educational websites in
to grad school — to pursue self-defined learning goals.
Industry
Online education
the world. Founded in 2005 by 15 year old Andrew
The site offers more than 15 million study sets for users,
Sutherland as a way to learn vocabulary for a high school
and hosts more than 1.2 million study sessions every day.
Location
San Francisco
visitors every month — more than doubling its user base
Employees
11
Use Case
Scale to meet increasing demand
while diagnosing performance
issues in near real time
Why JOYENT
Flexible cloud-based solutions built
on premium hardware and coupled
with superior network analytics
Why New Relic
Comprehensive visibility into
emerging issues across an
increasingly complex code base
French class, the site now attracts over 12 million unique
every year for six consecutive years.
Supported by ads, Quizlet offers its vast library of content
at no charge to students and teachers. In August 2012,
the company released an enormously popular iPhone
Quizlet has no pre-determined curriculum; instead, the
app, which attracted more than 1 million downloads in
company designs powerful, easy-to-use software that
a matter of months, making Quizlet the second most
empowers students of all ages — from grade school
popular free education app in the U.S. iPhone store.
Environment
Quizlet runs on a distributed Joyent Cloud environment, which includes the following components:
• Joyent SmartMachines and Cloud
• Sphinx full text search engine
• Traffic Manager load balancers
• Puppet configuration management software
• Percona database appliances
• SmartOS
• Apache HTTP Server
• PHP
• MySQL
• Node.js
• Memcached
• JavaScript and Ajax for client-side compute tasks
CASE STUDY: QUIZLET
Challenges
With its user base growing at an exponential rate, Quizlet is under
extraordinary pressure to keep pace with growing demand. “Over
the past 12 months, we’ve welcomed 70 million visitors,” says CEO
Dave Margulius. “Over the next 12, we expect 150 million. Many of
those users are in grade school, high school, or college — an audience
especially impatient with slow website performance. They just expect
the site to work and work fast.”
Faster page loads aren’t the only concern for Quizlet. Data reliability
is a major consideration as well, with users painstakingly uploading
“We’re committed to using the best available technologies
to help us grow and to give our users the best possible
online experience. The Joyent cloud, optimized with
New Relic monitoring, helps us operate with the kind
of efficiency and flexibility we need to deliver an even
better product to even more people.”
Dave Margulius
CEO, Quizlet
huge amounts of data every hour. “From the user’s perspective,
a significant portion of our reputation rests on storing and protecting
their hard work,” says Dave. “A reliable storage system that’s available
all the time, with no unplanned outages, is an absolute necessity for us.”
The Quizlet team knew that it needed a first rate cloud provider that
could scale quickly and easily to meet user demand. And in order to
keep the site running optimally, the company needed superior analytics
for quick diagnosis of performance issues in near real time.
“Before I joined the Quizlet team, I worked for other mission critical
websites that had the performance and stability issues you’d expect
from any large site,” says Ryan Gordon, DevOps and Backend Engineer
at Quizlet. “In those environments, we often didn’t know that something
was wrong until a user emailed us. And even then, we wouldn’t
immediately know the source of the problem. Was it the network?
Was it the code? Our troubleshooting process would always begin as
a guessing game. I’m so glad that Quizlet takes a different approach.”
Solution
Quizlet optimizes its cloud environment by turning to a combination
Quizlet’s increasingly complex code base. “It’s not just a matter of
of first rate vendors: a reliable cloud provider that can provide up to the
having the right cloud environment,” says Ryan. “You also need the
minute data on performance issues across the network and application
right tools to keep your environment running at its best.”
monitoring software that can pinpoint the source of any problem within
CASE STUDY: QUIZLET
“The combination of DTrace and New Relic is the
ultimate toolset for quickly identifying, isolating, and
correcting performance issues. We try to keep our
response time below 150 milliseconds from all of our
servers. And with these tools at our disposal, we can
get near real time statistics, right down to individual
CPU and memory.”
Ryan Gordon
DevOps and Backend Engineer, Quizlet
When Quizlet began looking for a cloud solution that would scale
quickly and easily to meet demand — all while providing 100% uptime
for users — Joyent was the easy and obvious choice. “The functionality
we get from Joyent’s SmartMachines gives us a totally robust, reliable
cloud environment that can handle big bursts in traffic,” says Ryan.
“It’s so easy to boot up our cloud servers, then resize them when we
need to. We’re also working with Joyent to establish a virtual LAN so
that we can increase security, communicate between multiple servers,
order to achieve comprehensive visibility across all aspects of its
environment, the company also needed an application monitoring
solution that would diagnose problems at the code level. That’s where
New Relic came in. “The combination of DTrace and New Relic is
the ultimate toolset for quickly identifying, isolating and correcting
performance issues,” says Ryan. “We try to keep our response time
below 150 milliseconds from all of our servers. And with these tools
at our disposal, we can get near real time statistics, right down to
individual CPU and memory. That’s hugely important in supporting
some of the more challenging aspects of Quizlet, like the audio
processing required for our text-to-speech feature.”
The Quizlet team relies on New Relic to monitor performance across all
web servers, taking a deeper dive whenever intensive troubleshooting
becomes necessary. New Relic even sends proactive email alerts
anytime the Quizlet environment crosses an unacceptable threshold.
“New Relic aggregates all of the available data for us, which gives us
visibility that we simply didn’t have before,” says Ryan. “The system
taps us on the shoulder when something demands our attention.
and rely on instant failover in the event of an outage.”
And when we need to take a closer look, we use Transaction Traces
With Joyent cloud services deployed on a robust ZFS layer, Quizlet
precise, granular level.”
had access to a powerful suite of network monitoring tools. But in
to identify slow logs, dig into query times, and fix problems at a really
Results
“I don’t know how I’d do my job without these analytic tools,” says
server’s response time. All three of those are crucial for assessing
Ryan. “I use them every single day. When I log into New Relic, the
the overall health of the site. And we use that throughput data to
first thing I see is the throughput, then the error rate, then the app
plan the implementation of heavy duty database changes, because
CASE STUDY: QUIZLET
we want to make sure that any adjustment will impact a relatively
small number of users.”
Popular education
learning site relies on
New Relic APM and
Joyent Cloud to meet
the learning needs for
students of all ages
around the world
With that level of visibility, the Quizlet team is in a far better position
to manage its world class Joyent environment more proactively and
productively. “These days, it’s unusual for users to catch a network
issue or coding issue before we do,” says Ryan. “And because we
can diagnose those issues more quickly than ever, we can put far
less energy into troubleshooting and far more energy into strategic
tasks that enhance the Quizlet experience for our users.”
“We have a big vision for this company,” adds CEO Dave Margulius.
the best available technologies to help us grow and to give our users
“We’re building a global Internet brand. Quizlet is here to create learning
the best possible online experience. The Joyent cloud, optimized with
tools that every student on earth can use, no matter where they live
New Relic monitoring, helps us operate with the kind of efficiency and
and no matter how affluent they may be. And we’re committed to using
flexibility we need to deliver an even better product to even more people.”
About New Relic
New Relic, Inc. is the all-in-one web application performance management provider for the cloud and the data center. Its SaaS solution, which
combines real user monitoring, application monitoring, and availability monitoring in a single solution built from the ground up, changes the way
developers and operations teams manage web application performance in real time. More than 30,000 organizations use New Relic to optimize
over 58 billion daily metrics captured. newrelic.com
About Joyent
Joyent is the high performance cloud infrastructure company, offering enterprises and developers the best public, private and hybrid cloud
infrastructure for today’s web and mobile applications. Joyent delivers public cloud services to some of the most innovative companies in the
world, including Quizlet, LinkedIn, Voxer, and Modcloth, and licenses the software that runs its public cloud to enterprises wishing to operate
their own private or hybrid clouds. For more information, visit http://www.joyent.com/
© Copyright 2012, New Relic, Inc. All rights reserved. All trademarks, trade names, service marks and logos referenced herein belong to their respective companies. 11.20.12