Leading FinTech Company Boosts SaaS User Experience

and Slashes Cloud Bills With Opsani


The company’s performance team were trying to tune the Java environment of the application UI, which generates the SaaS UI from the backend infrastructure (without displaying databases, authentication and other elements that aren’t relevant to a user). The company’s performance team’s primary goal was to improve user experience. A key part of achieving this was reducing latency, which sat stubbornly at 150 milliseconds across dozens of shards. The company also wanted to reduce the frequency of “GC full events” occurring in Java Virtual Machines (JVMs). Whenever they occur, GC full events can slow down an application, consume excessive CPU, and impact the user experience.

If the company’s team could reduce latency and minimize GC full events, they would increase availability, make the UX snappier, and produce more of a real-time interaction for users. As well as implementing these user-friendly improvements, they would also trim their AWS bill – which they knew was higher than it needed to be – without any negative impact upon performance.

However, effective human tuning of the Java environment was proving impossible. Despite the efforts of the SaaS tuning team, the performance was inconsistent between releases. This was having an ongoing impact on user experience, which was intermittently less than optimal. And their cloud bills were staying the same, despite the tuning team knowing that application parameter optimizations were possible.

Executive Brief

The company is the industry leader in financial, accounting, and tax preparation software, with annual revenue of almost seven billion dollars. Their SaaS service, is one of their key product offerings and is utilized by millions of global businesses.

Industry Financial Services
App Resources 1000s of Virtual Machines
Time to Optimize Less than one quarter

The company turned to Opsani to implement AI-driven cloud optimization and achieve their goals for their SaaS application.

Over one month, the Opsani cloud optimization tool:

Cut application latency by 10%

Recovered 5,000 minutes of uptime

Restarts decreased by 78%

Trimmed AWS EC2 bill by 72%

Optimization Challenge

The optimization challenge was significant. Cloud applications are by nature extremely complicated, offering trillions of resource and parameter permutations. Runs over 10,000 transactions per second. To reduce latency, the Opsani cloud optimization engine targeted a variety of changes:

  • Number of instances per shard (on the horizontal scale).
  • EC2 instance type/family (on the vertical scale).
  • Five different Java config parameters affecting Garbage collection strategies, intervals, and heap sizes. And this barely scratches the surface of what can be tweaked to improve the performance of a cloud application.

These parameters are all interrelated, offering trillions of possible combinations. The Opsani engine optimized for work done – number of transactions completed – while maintaining the service-level objective (SLO) – response time, error rate – and minimizing the cost. The cost was computed as the price of one of the selected instance types multiplied by the number of instances.

The Opsani engine examined the trade-off between having many cheap nodes as compared to fewer, larger nodes. Different instance types affected the amount of memory available for Java Heap, so different heap sizes had to be explored as a dependent variable. Moreover, for their shards serving the US market, Intuit could reduce their total number of compute instances by going with VMs with more memory.


After the optimization period, The company’s SaaS application experienced a host of performance benefits:

  • Faster application response time: 90% percentile (TP90) latency time improved by 10%
  • A total of 5,000 minutes of uptime were recovered within 2 weeks
  • Operations experienced a 10x reduction in pager notifications
  • “GC full events” decreased by 91%
  • Release cycles made quicker by an entire week

Opsani’s cloud optimization enabled a major FinTech player to unlock major cost savings.

On top of this, Opsani’s cloud optimization enabled The company to unlock major cost savings. Prior to starting cloud optimization, the company’s team was expecting cost savings of at best of 20%. However:
With Opsani, the cost came down by 72%, equating to hundreds of thousands of dollars cut from the monthly AWS bill.

The company was so impressed with the benefits of cloud optimization that over the coming months they are expanding the technology across more of their applications.