Practice memory profiling vocabulary: heap snapshots, memory leaks, GC pressure, event listener leaks, retained objects, and heap dump analysis.
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'The ___ snapshot shows retained objects.' Which noun describes a capture of the memory heap?
A 'heap snapshot' captures the state of the memory heap at a point in time. By comparing snapshots before and after an operation, you can identify objects that are growing or not being garbage collected.
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'The memory leak is in the event ___.' Which noun completes this common leak source?
'Event listener leaks' are the most common memory leak in Node.js and browser JavaScript. Registering listeners without removing them causes references to accumulate and prevents garbage collection.
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'GC ___ is high — 30% of CPU is GC.' Which noun describes the load on the garbage collector?
'GC pressure' describes how frequently and for how long the garbage collector must run. High GC pressure (30% CPU on GC) means the application is allocating objects faster than GC can reclaim memory.
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'We found a 200MB ___ after 24 hours.' Which noun describes memory that grows but never releases?
A 'memory leak' is memory that is allocated but never released because references to it persist. A 200MB leak after 24 hours suggests a gradual accumulation that would eventually crash the process.
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What is a 'heap dump' used for?
A heap dump is a binary snapshot of the entire heap. Tools like Eclipse MAT (Java) or Chrome DevTools (Node.js) analyze heap dumps to find the largest retained objects and the 'dominator tree' of memory usage.