Concurrent Priority Queue in .NET 4.0

Question

It seems there are lots of improvements in .NET 4.0 related to concurrency that might rely on concurrent priority queues. Is there decent priority queue implementation insid

Answer 1

Recently, I was creating a state machine in which I needed time-stamped events. Rather than just a simple clock tick, I needed timed events with their own IDs so that I could distinguish one event from another.

Researching this problem led me to the idea of using a priority queue. I could en-queue the timed events along with their information in any order; the priority queue would take care of ordering the events properly. A timer would periodically check the priority queue to see if it is time for the event at the head of the queue to fire. If so, it de-queues the event and invokes the delegate associated with it. This approach was exactly what I was looking for.

Searching here at CodeProject

https://www.codeproject.com/Articles/13295/A-Priority-Queue-in-C

I found that a priority queue[^] class had already been written. However, it occurred to me that I could easily write my own using my old friend, the skip list. This would have the advantage that the de-queue operation would only take O(1) time, while the en-queue operation would still be log(n) on average. I thought that using skip lists in this way was novel enough that it merits its own article.

So here it is. I hope you find it interesting.