SshClient - thread gets blocked indefinitely, lock not released

Using version 2020.0.0-beta1 SshClient, I was doing some load testing, and consistently encountered an issue when executing commands for an extended period of time using a single client instance (a few hours running around 1M commands).

When running the SshCommand.Execute() method, the method SemaphoreLight.Wait() waits for a lock to be released indefinitely. (SemaphoreLight.cs : Line 110)

Call stack:
System.Private.CoreLib.dll!System.Threading.Monitor.Wait(object obj, int millisecondsTimeout, bool exitContext)
Renci.SshNet.dll!Renci.SshNet.Common.SemaphoreLight.Wait()
Renci.SshNet.dll!Renci.SshNet.Channels.ChannelSession.SendChannelOpenMessage()
Renci.SshNet.dll!Renci.SshNet.Channels.ChannelSession.Open()
Renci.SshNet.dll!Renci.SshNet.SshCommand.BeginExecute(System.AsyncCallback callback, object state)

As a workaround, disposing and recreating the SshClient object after every 10000 executions solved the problem.

Inizia da SshCommand.Execute e dal relativo percorso di chiamata verso BeginExecute, quindi esamina ChannelSession.Open e SemaphoreLight.cs intorno alla riga 110. Riproduci il test di carico di lunga durata descritto nell’issue usando un SshClient e osserva dove l’attesa rimane bloccata. Il lavoro è completato quando l’esecuzione prolungata di un comando non lascia più il client in attesa indefinitamente.