After upgrading to SC 4.2 (as well as all the plugins), I have MSSQL transaction log truncate jobs that run every 20 minutes that aren't showing as completed. At last check, the dashboard shows 2277 running jobs. Investigating these jobs shows that they are completing, but it looks like the thing that isn't, or isn't registering as completed, is the last step which, in the logs, shows as "GetPluginLogsZipAsync." I assume that this is some log gathering process? As I said before it's either never finishing or never registering itself as being completed.
The above is my guess as to why all these jobs still appear as "running" even though all the logs end with "completed" or "exit" or something that shows completed steps. This problem concerns one Resource Group made up of about 13 MSSQL instances. They're all in the same data center as the storage and the SC host. The only job associated with this RG is a log truncate. The job runs every 20 minutes and seemingly completes.