[NIFI-4609] RemoteSiteListener creates and starts worker threads without bound.

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Assignee: Mark Payne
• Reporter: Marc Parisi
• Created: 15/Nov/17 15:31
• Updated: 15/Nov/17 16:12

Description

MiNiFI C++ will continually attempt to reconnect to a NiFi instance. In RemoteSiteListener if something happens to the connection the thread does not appear to go away and it is unbounded. So if you had many connections come in, thread.start will create n threads without bound. This was experienced on an RPI where something happened to the connection and we abandoned it on MiNiFi C++ ( but socket hasn't been closed yet). Since we don't have insight into what's occurring on the server side we make an attempt to reconnect, thus creating a new Thread.

Might suggest an ExecutorService to coordinate these threads and potentially an AfterExecute to perform some accounting for visibility.

https://github.com/apache/nifi/blob/45f82dc855177702a0c1a0e4c38af334b713c278/nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-site-to-site/src/main/java/org/apache/nifi/remote/SocketRemoteSiteListener.java#L310

jeremy.dyer can provide additional insight.