Unhandled Exception: System.IndexOutOfRangeException

[evan]

The following fatal exception occurs in our app:

Unhandled Exception: System.IndexOutOfRangeException: Index was outside the bounds of the array.
  at System.Collections.Generic.List`1.Add(T item)
  at StatsdClient.Statsd.Add[TCommandType](String name, Double value)
...

I believe this may be a thread safety issue. Is access to the Commands List thread safe?

[evan]

It is not. I believe you want to use a ConcurrentQueue here.

[DarrellMozingo]

Hi Evan,

I took a look at this and was able to reproduce when hitting the Add method with upwards of a million concurrent calls. ConcurrentQueue won't work here because a) we're still targeting .NET 3.5 and ConcurrentQueue is in 4.5, and b) the List type is on the IStatsd interface (unfortunately), so I don't want to break that contract for anyone.

I'll give a go at doing some basic thread locking to see if it'll solve the issue. If not, we may look at breaking the two points above and using one of the newer built in thread safe types.

Thanks for reporting this!

[DarrellMozingo]

Just pushed this in 1.0.0.17. Let me know if you have any problems.