Queue<T> vs List<T>

.net performance list queue difference
Jack picture Jack · Apr 30, 2012 · Viewed 48k times · Source

I'm currently using a List<T> as a queue (use lst[0] then lst.removeAt(0)) to hold objects. There's about 20 items max at a given time. I realized there was an actual Queue<T> class. I'm wondering if there's any benefit (performance, memory, etc.) to using a Queue<T> over a List<T> acting like a queue?

Answer

Adam Houldsworth picture Adam Houldsworth · Apr 30, 2012

Performance can be profiled. Though in this case of so few items, you may need to run the code millions of times to actually get worthwhile differences.

I will say this: Queue<T> will expose your intent more explicitly, people know how a queue works.

A list being used like a queue is not as clear, especially if you have a lot of needless indexing and RemoveAt(magicNumber) code. Dequeue is a lot more consumable from a code maintenance point of view.

If this then gives you measurable performance issues, you can address it. Don't address every potential performance issue upfront.

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