Day 33 of 60 · Load, chaos, durability

Soak / endurance testing

Your hour-long load test passed. Then production ran for a week and the heap quietly filled up. Soak tests find what only time exposes.

ProblemMemory leaks, file-descriptor leaks, slow drift under sustained load.

How it works

Run the system at moderate, sustained load for hours or days. Watch RSS, FD count, latency drift.

What it catches

Memory leaks, resource exhaustion, latency degradation over time, scheduled-job interference. Hidden in shorter runs.

Tools

k6 long-run · OSS Locust + Grafana · OSS

Verdict by project size

Small
Skip
Medium
Opt
Large
Rec
Extra-large
Must

Cost

Project size Setup Maint / mo Tool / mo CI / run
Small <10k LOC 4h 0.5h $0 ,
Medium 10–100k LOC 2d 2h $0 ,
Large 100k–1M LOC 5d 10h $200 ,
Extra-large >1M LOC 20d 40h $2k ,
Setup = engineer-days to first useful run · Maint = engineer-hours / month at steady state · Tool = out-of-pocket $ / month · CI = minutes added (or saved) per pipeline run

Lifecycle & ownership

When in lifecycle
Test Release Operate
Per release · Runs before promotion to production.
Who owns it
SRE / DevOps / Platform
CI/CD, observability, reliability
Collaborates with: Developer

Reference implementations

Quick check

Soak / endurance tests are designed to expose…

One question. Pick the best answer. Your streak is saved locally on this device.

Save the lesson

Download SVG ↓

Screenshot for a 1:1, drop it in Slack, or download the SVG.

thinkbridge THE VALIDATION ATLAS DAY 33 OF 60 LOAD, CHAOS, DURABILITY Soak / endurancetesting Your hour-long load test passed. Then production ran for aweek and the heap quietly filled up. Soak tests find whatonly time exposes. FIVE-MINUTE LESSON · ONE QUICK-CHECK QUESTION There’s a new way there
All 60 days →