Index · Common pitfalls | Performance

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Index · Common pitfalls

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Rapid overview

Bad Practice	Why it’s bad	Fix
Using `new` objects inside tight loops	Floods Gen 0	Reuse pooled objects
`string.Concat` or `+` in loops	Creates new string every time	Use `StringBuilder` or spans
LINQ in hot paths	Allocates enumerators, closures	Use `for` loops
Boxing value types	Allocates on heap	Use generics / avoid casting to `object`
Repeatedly allocating buffers	LOH churn	Use `ArrayPool<T>`
Returning large arrays	LOH growth	Reuse pooled arrays or slice spans