Now this is a nice bug that was found accidentally by ArchiBoT...
ReaderWriterLockSlim() is very decent solution, but it's thread-based, and we're using our ConcurrentHashSet in mixed async/sync context. This means that if we use something like:
foreach (var item in concHashSet) {
await AnythingAsync().ConfigureAwait(false);
}
It's totally possible that we'll request read lock as thread 1, and release the read lock as thread 2, which will lead to RWLock exception => System.Threading.SynchronizationLockException: The read lock is being released without being held.
Fortunately it looks like we didn't have any scenario like this in ASF, as this was possible only when we async/await while enumerating over ConcurrentHashSet, so that specific bug didn't affect ASF codebase (yet). Still, I must fix this as current implementation is not thread-safe, so our HashSet is in fact not concurrent in the first place.
I analyzed possible solutions and there are basically 3: either using ConcurrentDictionary and wrapping around it, replacing lock with SemaphoreSlim, or using third-party AsyncReaderWriterLock from StephenCleary. SemaphoreSlim entirely kills the concept of multiple readers one writer, and could affect performance negatively, moreover - it doesn't support upgreadable lock scenario we have with ReplaceIfNeededWith(). Concurrent dictionary would be nice if I didn't have that awful memory hit from storing mandatory pointless value, plus I don't really like concept of wrapping around conc dictionary if I can simply use it right away and drop my conc hashset entirely. AsyncReaderWriterLock seem to be really well written, and works on Mono + should be compatible with .NET core in the future, so we should go for it as it's the best bet both performance-wise and memory-wise.
This brings another package dependency and changes a bit backend of ConcurrentHashSet
We should finally start using latest SK2 enhancements, some of which I added myself to official SK2 repo.
I hope this solves various network quirks that suddenly arrived either with Steam network, or ASF code changes regarding HeartBeats.
The .dll bin is self-compiled from latest SK2 repo, I hope I can drop it when SK2 arrives on nuget, but when it happens - not sure, while I want to test if this fixes particular issues that are happening lately.
ASF is AnyCPU binary which means it'll run fine on both 32-bit as well as 64-bit OSes.
Up to today 32-bit runtime was preferred for ASF, as it uses less memory and can be faster than 64-bit equivalent.
However, in very busy environments it's easily possible for ASF to require even more than 2 GB of memory, and in addition to that extending our userspace to 64-bit can bring benefits on more modern setups.
Therefore, keep being compatible on both 32-bit and 64-bit OSes, but on 64-bit ones use actual 64-bit runtime instead of preferred 32-bit one.
In addition to that, optimize some unused references and other things while we're at it.
After evaluation, it seems that more accounts have card drops restricted rather than not, and having it as true when in reality it's false results in less performance degradation than the other way
