Hi again. I had trouble sorting an out-of-order action processing error, which was causing clients to be kicked. I thought that was when the client fires two actions, and their processing on the server may get interleaved as they have async calls, but I fixed that by making the server listeners quick and sync, and the problem still occurred. I've been unable to repeat it locally and with test code, but it happens on the cloud hosted server and actual use sometimes. So after not being able to fix it, I did this terrible hack experimentally, to just tolerate unordered processing of actions, in the case where the order does not matter, and everything seems to work great now 😮 I wonder what all that breaks, though. I haven't found any problems so far. in PlayerActorBase HandleFlush

csharp
    else if (nextUnsynchronizedServerAction.TrackingId != unsynchronizedServerActionMarker.TrackingId)
    {
        //_log.Warning("Unsynchronized server action rejected. Out of order. Expected id {ExpectedId}, got: {ActionId}", nextUnsynchronizedServerAction.TrackingId, unsynchronizedServerActionMarker.TrackingId);
        _log.Warning("Unsynchronized server action detected as Out of order. Expected id {ExpectedId}, got: {ActionId}. HACK FIX: am tolerating this! --antont", nextUnsynchronizedServerAction.TrackingId, unsynchronizedServerActionMarker.TrackingId);
        //throw new InvalidOperationException($"PlayerFlushActions, trying to re-order Unsynchronized Server Action");
    }

The hack doesn't break anything, except allows clients to "run" unsynchronized actions in a different order than server. But that doesn't really matter as server is the authority. With async interleaving yea I can see this happening.

ExecuteServerActionImmediately

tries to prevent callers from non-actor-current thread exactly to avoid races. Not sure why that didn't work here. But with sync calls, I don't really see how the order could get mixed up in the first place. A tip: if you have async operations that may complete in various orders, one easy way to order/linearize them is to use

ExecuteOnActorContextAsync

and push the result handling to the actor thread. So in this case, we could compute stuff in the async continuation, but finally to apply the result, we could do

ExecuteOnActorContextAsync(() => ExecuteServerActionImmediately(action))

yep that's what i do now, and the error got really rare i've still gotten it a couple of times in a day, when i checked it late last week, will check soon again