.NET Memory, GC & Performance Essentials

GC generations and reachability, leaks and allocation pressure, deterministic cleanup, lifetime mistakes, large-object and streaming design, bounded caches, measured allocation reduction, safe pooling, production memory diagnosis, high GC CPU, and out-of-memory recovery.

15 drillsPractice one at a timeOrdered pathConcept questionComparison questionDebugging scenarioCode review

Recommended start

.NET GC Generations

Introduces managed heap cleanup, generational collection, object lifetime, and why allocation behavior affects .NET services.

Easy~5 minStep 1 of 15

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1.NET GC GenerationsRecommended startIntroduces managed heap cleanup, generational collection, object lifetime, and why allocation behavior affects .NET services.Concept questionEasy~5 min.NETC#Practice 2Object ReachabilityExplains how GC roots retain reachable object graphs and turns heap evidence into a concrete ownership fix for static state, events, closures, queues, and caches.Concept questionMedium~7 min.NETC#Practice 3Leak vs PressureClarifies the difference between objects being retained accidentally and code simply allocating too much temporary memory.Comparison questionEasy~5 min.NETC#Practice 4Dispose vs FinalizerDistinguishes deterministic cleanup from finalization and explains resource ownership in normal application code.Comparison questionMedium~7 min.NETC#Practice 5Async DisposalExplains asynchronous cleanup for resources whose shutdown path needs async work, such as flushing or closing remote connections.Concept questionMedium~7 min.NETC#Practice 6Event LeakShows how publisher-to-subscriber references can retain objects and how to clean up event-based lifetimes.Debugging scenarioMedium~10 min.NETC#Practice 7Singleton CaptureReviews a captive scoped dependency as both a lifetime and concurrency bug, then replaces it with explicit per-operation scopes and minimal immutable work data.Code reviewHard~12 min.NETC#Practice 8Large AllocationsCovers the Large Object Heap, big buffers, fragmentation pressure, and practical ways to avoid loading too much at once.Concept questionMedium~7 min.NETC#Practice 9Streaming DataCovers large exports, uploads, and API responses where bounded memory matters more than convenience.Architecture scenarioMedium~10 min.NETASP.NET CoreC#Practice 10Unbounded CacheExplains cache memory growth, eviction, size limits, stale data, and why cache design needs explicit bounds.Architecture scenarioMedium~10 min.NETASP.NET CoreC#Practice 11Hot Path AllocationsFrames allocation reduction as measurement-driven API work rather than premature micro-optimization.Architecture scenarioMedium~10 min.NETASP.NET CoreC#Practice 12Span and PoolingIntroduces lower-level allocation tools while emphasizing measurement, ownership, and safe usage.Concept questionHard~9 min.NETASP.NET CoreC#Practice 13Memory Growth InvestigationGives a practical incident flow for memory growth using metrics, traffic correlation, heap evidence, and safe mitigation.Debugging scenarioHard~12 min.NETASP.NET CoreC#Practice 14High GC CPUCovers allocation rate, collection frequency, latency symptoms, and safe production steps for GC-heavy services.Debugging scenarioHard~12 min.NETASP.NET CoreC#Practice 15OOM ResponsePractices incident response after an OOM: restore service, collect evidence, identify trigger, and prevent recurrence.Debugging scenarioHard~12 min.NETASP.NET CoreC#Practice