# Optimize backend performance for content-driven web apps

For any type of scaling, consider the architecture of your application and what
optimizations may be possible. For example, [static content should be served
from optimized content delivery networks](https://developers.google.com/solutions/content-driven/hosting/cdn)
that offer price and performance benefits. Additional [caching for the data
storage
backend](https://developers.google.com/solutions/content-driven/data-storage/performance-optimization#cache)
may also improve performance and minimize the requirements for expensive
scaling.

## Performance testing and benchmarks

Benchmarking and performance testing can identify potential performance
bottlenecks during development, help track trends over time, and support
decision making by comparing architectures, technology stacks, cloud providers,
or other options.

**Load testing** uses predetermined, controlled types of load, traffic, or data
to measure the performance of your backend against your targets. You can see how
various load levels impact your application's performance.

**Scalability testing** focuses on analyzing your application's ability to
[scale up and scale out](https://developers.google.com/solutions/content-driven/backend/scaling). Scalability
testing shows how your application responds to increased loads and how the
backend (including data storage) adapts.

Define clear targets before beginning to benchmark the application, including
performance and speed (for example latency, throughput, speed), resource
utilization (CPU utilization, memory usage, network traffic between backend
components), and cost. Consider any delays in scaling; for example, if the
application needs to scale beyond an allocated set of "reserve" resources when
bursts or spikes in traffic occur.

Many tools are available for benchmarking and performance testing, such as
[Apache JMeter](https://jmeter.apache.org/) and
[Locust](https://locust.io/). When selecting a testing tool,
consider the types of tests that are available, including whether or not you
need support for scripting, IDE integrations for debugging, additional plug-ins,
or support for the kind of traffic and scale to be tested.

If using a cloud provider, determine if there are any additional requirements or
best practices for any load testing to avoid potential restrictions. For
example, consider the best practices for [Cloud
Run](https://cloud.google.com/run/docs/about-load-testing).

## Cost and performance considerations

While scaling up is essential to improve performance, scaling down should also
be a consideration to minimize cost. Consider the baseline cost of your backend
application without any requests and the cost involved in scaling up the
application.

You may have fixed costs for on-premise or server-based architectures,
regardless of utilization. Some cloud environments allow you to *"scale to
zero"* to avoid costs when no requests are made. Cloud providers offer
calculators for you to explore different configurations and pricing strategies,
such as pre-commitments for resources.