Performance Testing
The reality about application performance
Many organizations only discover capacity issues at the worst possible moment: during a live campaign, at a peak time, or after a major deployment. The consequences are predictable — slow response times, time-outs, downtime, and frustrated users.
What you don't know without performance testing:
- Where bottlenecks occur — in application code, database, caching layer, or infrastructure
- At what user volume response times become unacceptable
- How the system reacts to sudden spikes (spike testing)
- Whether your system remains stable under prolonged load (endurance testing)
- Which dependencies — third parties, APIs, microservices — pose the greatest risks
- Whether your scalability and auto-scaling work correctly under real load
A performance test makes this visible with data — not assumptions.
What DEFION Performance Testing concretely delivers
Our specialists conduct targeted tests tailored to your architecture, usage patterns, and growth expectations:
✔ Load testing — Simulation of expected user volume to determine basic behavior and response times
✔ Stress testing — Load beyond the expected maximum to identify breaking points
✔ Spike testing — Sudden, extreme peak load to measure stability
✔ Endurance testing — Prolonged, sustained load to detect memory leaks and degradation
✔ Scalability testing — Validation of horizontal and vertical scaling options
✔ Bottleneck analysis — Identification of slow queries, inefficient code, misconfigurations, and infrastructure limits
✔ Reporting at both technical and management levels — Findings, visualizations, and priority list
✔ Capacity plan — Substantiated advice for scaling plans, budgeting, and infrastructure investments
Not a theoretical exercise. Measurable insights based on real load profiles.
The four test types used by DEFION
Load Test
The basics: how many concurrent users can your system handle without response times deteriorating? We create load profiles based on your actual traffic data and future expectations — not on assumptions.
Stress Test
We push your system beyond the expected maximum to determine where it breaks, how it fails, and how it recovers. A controlled stress test prevents an uncontrolled production outage.
Endurance Test
Some issues — memory leaks, connection pool exhaustion, resource drift — only manifest under prolonged load. Our endurance tests run for hours to days to expose these creeping problems.
Spike Test
Flash sales, viral moments, campaign launches: sudden traffic storms without warning. We simulate unexpected spikes to validate that your infrastructure and auto-scaling respond in time.
How a performance test at DEFION proceeds
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Intake & objectives
Together we determine test goals, usage scenarios, acceptance criteria, and peak load profiles. Which scenario is the most critical for your organization? Which components must definitely hold up? -
Test design & preparation
We configure realistic load scripts based on your actual user behavior. Monitoring is set up on all relevant layers: frontend, backend, database, infrastructure, and external dependencies. -
Execution
Tests are conducted within agreed time windows, preferably in a production-representative environment. We continuously monitor to prevent escalation and adjust parameters where necessary. -
Analysis & bottleneck identification
After the tests, we systematically analyze all measurement data. We identify where delays occur, why, and how severe the impact is on end-user experience and availability. -
Reporting & improvement advice
You receive a clear report with findings, visualizations, and a priority list. Recommendations are directly applicable for your development and infrastructure teams — with concrete adjustments, no vague advice.
For which organizations is performance testing essential?
Performance tests are indispensable for:
- E-commerce and online platforms where slow loading times directly cause conversion loss
- SaaS providers with SLA obligations towards customers and uptime guarantees
- Organizations for planned peak moments — product launches, Black Friday, tender deadlines
- Financial institutions and other regulated sectors where availability is a legal requirement
- Public service providers where system failure has societal impact
- Organizations migrating to new infrastructure, cloud environments, or microservices architecture
- Development teams who want to validate that a new release does not degrade existing performance
Why DEFION — and not a generic testing party?
Security context built-in
Performance testing at DEFION is not separated from security. During tests, we also detect configuration errors, insecure default settings, and architectural choices that affect both performance and security — and report these.
Born from twenty years of technical fieldwork
DEFION originated from Computest Security and Incide. Our testers understand not only load testing tools but also the underlying architectures — from monolithic legacy systems to modern cloud-native microservices and OT environments.
IT and OT
Where necessary, we also perform performance tests on industrial environments and process control networks — tailored to the specific operational constraints of OT.
No standard tooling output
We do not deliver raw JMeter or Gatling reports. We interpret the data, set priorities, and translate findings into concrete actions for both engineers and management.
"Thanks to DEFION, we benefit from up-to-date knowledge about contemporary security threats and ways to prevent risks. We have peace of mind knowing that we are fully supported by their team 24/7." AFAS Software
"Thanks to DEFION, we benefit from up-to-date knowledge about contemporary security threats and means to avert risks. We have peace of mind knowing we are fully supported 24/7 by their team.”
Jeroen van Stokkum Manager ICT
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“The sector and the partners we work with maintain increasingly high security standards for IoT-products and services. Protecting the privacy of individuals in the images and the sensitivity of the information the drones collect, such as on objects in critical infrastructure, requires our security to be airtight. With Defion, we are working with a professional partner who can support us at the right level. The collaboration also fits perfectly within our strategy to deliver reliable and secure drone technology to European customers.”
Benjamin van der Hilst Co-Founder & CEO
“New requirements from NIS2 for OT systems are increasing the focus on security. With Defion, we know we have the right expertise in-house to keep our systems secure. The collaboration was easy and pleasant; the specialists truly sat next to us rather than across from us. Thanks to their openness and expertise, we are working together toward the same goal: optimal security. This gives us the confidence to face the future.”
Alexander OdijkTeam Manager
“If you look at where we were ten years ago, we’ve made enormous progress. The sense of control is greater. With Security Assurance and MDR we have set up processes and control mechanisms that allow us to limit the impact of a potential attack. The collaboration also serves as a constant reminder to maintain focus on security and set the right priorities in that area. It keeps us alert and sharp. Moreover, Defion’s specialists are highly technical and passionate about their field. That clearly shows in their services.”
Gerco VermeerDevelopment Manager
