fixed race condition with creating priority queue #2447
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| @@ -2614,6 +2614,8 @@ namespace Akka.Dispatch.MessageQueues | |||
| } | |||
| public class UnboundedPriorityMessageQueue : Akka.Dispatch.MessageQueues.BlockingMessageQueue | |||
| { | |||
| [System.ObsoleteAttribute("Use UnboundedPriorityMessageQueue(Func<object, int> priorityGenerator, int initia" + | |||
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Marked all of the methods that don't have you explicitly set the priorityGenerator at construction time as obsolete.
| @@ -4853,14 +4855,17 @@ namespace Akka.Util | |||
| public override bool IsRight { get; } | |||
| public TA Value { get; } | |||
| } | |||
| public class ListPriorityQueue | |||
| public sealed class ListPriorityQueue | |||
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There's no really means for extending this queue given that all of the important parts of it are private fields.
| @@ -12,63 +12,63 @@ | |||
| namespace Akka.Dispatch.MessageQueues | |||
| { | |||
| /// <summary> | |||
| /// Base class message queue that uses a priority generator for messages | |||
| /// Base class for a message queue that uses a priority generator for messages | |||
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Tried to fill in all of the TBDs that @sean-gilliam left as placeholders.
| { | ||
| _data = new List<Envelope>(initialCapacity); | ||
| _priorityCalculator = priorityCalculator; |
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Set all of the guts of the priority queue in the same place...
| { | ||
| _prioQueue.SetPriorityCalculator(priorityGenerator); | ||
| _prioQueue = new ListPriorityQueue(initialCapacity, priorityGenerator); |
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This is the key fix: create the queue WITH its priority generator at the same time and never change it again. That way we don't end up in a situation where the mailbox is having messages queued into it while the underlying priority generator is being changed concurrently on another thread.
close #2308 - realized that this was the result of a weird design choice on my part back when we were working on releasing 1.1. Should never change the priority generator function at runtime. Now it's set via a constructor and is immutable, which should eliminate the issue.
CC @ronnieoverby