Reviewed-by: Frazer Clement <frazer.clement@oracle.com>
Reviewed-by: Mauritz Sundell <mauritz.sundell@oracle.com&gt;a>

Fixing some issues with main thread when restoring metadata where the
heartbeats weren't sent properly due to signals in main thread
executing for too long and thus no chance for heartbeats to be sent.

Handling ENOMEM with resends of smaller size when send attempted.
Optimised DIH handling of LCP_FRAG_REP.
Added a number of extra debug information when reporting that thread
is not responsive.
Some debugging of memory sizes of process added.