GUI might freeze when downloading multiple Hive jobs concurrently

[gkronber]

I ran into what seems to be a GUI deadlock today while I was downloading Jobs from the Hive Server (multiple downloads concurrently).

The threads stopped in the following methods:

• HeuristicLab.Clients.Hive.JobManager.Views.RefreshableHiveJobView.OnContentChanged
• HeuristicLab.MainForm.WindowsForms.AsynchronousContentView.Invoke
• System.Windows.Forms.Control.WaitForWaitHandle

The GUI froze but execution of algorithms in the background was not affected.

RefreshableHiveJobView.OnContentChanged contains a lock() statement. The code in OptimizerHiveTask contains operations with ReaderWriterLocks. I presume the observed behavior can be traced back to these methods.