Advanced – Non-Functional Testing
Deadlock – ISTQB Definition
Last Updated: July 12, 2026 · SoftwareTestPilot QA Team
Official ISTQB Definition
A situation in which two or more processes are unable to proceed because each is waiting for one of the others to do something.
In simple words
Two processes each hold a lock the other needs — both freeze forever.
Exam tip
Prevention: consistent lock ordering, timeouts, and lock-free structures.
Related terms
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