Understanding and Resolving PHP Memory Leaks with APM Insights

In the 2025 PHP Trends Report, performance bottlenecks ranked high on developers’ lists of ongoing challenges, and PHP memory leaks were pinpointed as a frequent culprit especially in high-traffic environments

Is Your App Slowing Down Unnoticed?

Imagine your application performed flawlessly during testing but weeks after launch, you start seeing rising latency and occasional failures. Logs don’t flag anything obvious. Yet memory usage steadily climbs until PHP-FPM workers begin to crash. That’s a classic memory leak in action where a problem that hides during short tests but builds up under sustained production traffic

What Are PHP Memory Leaks, and Why Do They Matter?

Although PHP is garbage-collected, not all memory is released automatically especially in complex or long-running contexts. Common causes include:

• Circular references: When objects reference each other, the garbage collector may not flag them as discardable

• Persistent connections/resources: Unclosed database or API connections, file handlers, or sockets can accumulate across requests

• Misbehaving C extensions: Extensions that allocate memory outside PHP’s management may fail to clean up properly

• Memory-heavy structures: Holding large arrays or data without pagination, or caching results without pruning logic, can lead to uncontrolled memory growth

Detecting Memory Leaks

Start by instrumenting your code:

• Use memory_get_usage() and memory_get_peak_usage() to measure consumption at critical points.

• Observe PHP-FPM or worker processes via system logs, steady upward trends hint at leaks Atatus.

• Employ APM tools like Atatus to visualize memory trends, trace request lifecycles, and flag anomalies in real time

APM to the Rescue: Pinpoint, Then Fix

APM (Application Performance Monitoring) platforms go beyond reactive alerts when they equip teams to proactively track memory behavior. Here’s how:

Why Atatus Stands Out?

Atatus APM goes further by delivering:

• Full-stack visibility from backend code and DB calls to memory profiling and background jobs

• Real-time memory tracing: catch leaks before they escalate

• Easy setup: lightweight, zero-config agent deployment

• Contextual insights: link memory trends with errors, latency, or CPU spikes

• Built for all team workflows such as devs, DevOps, SREs with scalable and intuitive dashboards

Final Thoughts: Don’t Let Memory Leaks Jack Your App

Memory leaks may not crash your app overnight, but they drain performance over time like slowing response times, increasing failures, and eroding user trust. Relying on logs and manual debugging isn’t enough anymore.

With an APM like Atatus, you gain not just visibility, but actionable insight to spot trouble early, understand its origin, and optimize your PHP stack before users are affected.

Start your free trial and see how real-time observability transforms memory leak management.