we experienced an "issue" when using the gfal2 python bindings with the gsiftp:// protocol. However, this does not concern the gridftp-plugin but rather the python binding code itself.
When a context is used to execute a command that involves gsiftp://, a ftp connection is opened and kept alive as long as the context (or more precisely, the C++-library-based context instance ("C-context")) exists. The Py-context has no explicit destructor _del_ that invokes the C-context destructor, so the actual destruction, and thus, the closing of open ftp connections only takes place when the Py-context instance is garbage-collected. Potentially, this means that you cannot close connections manually unless you keep track of all references to that Py-context instance which can be quite difficult in more complex use-cases.
I would propose to add an explicit destructor in order to improve the control over open ftp connections.
Thanks for considering this feature request.