There appears to be a memory leak in the http_mi module, Opensips 1.8.2.
When package memory is set to 4MB the memory leak becomes apparent after a few hours.
When the package memory is set to 64MB after a few days.
The HTTP Requests begin to fail with Error 500 and the log shows "ERROR:core:init_mi_tree: no more pkg mem".
This has only started to happen after switching from xmlrpc to mi_http.