Thank you for your response. Appreciate the interest. So often problems are solved in terms of "what I have or do."
It does appear that memory is not the issue. Deep within the program it appears that Spam and Virus checking defaults to non-checking. In other words, that is not source of memory leak.
This was a significant problem. The site would just die and I would get no emails for a few hours and it would start again.
It is taken me months to learn that virtual hosting using Amazon Web services requires very specific coding. If does not follow exact conventions it does not work perfectly. 1st, you must use the private not public IP address.
This how a typical AWS virtual host must be written. This is specific to AWS. Others may not experience the same problem although I know AWS is very common now. The directory is not essential but it must be correctly pointed to the exact directory. I chose to use a much more secure directory.
So it appears for now the 000-default.conf and default-ssl.conf were the cause of the problem. Not perfectly coded. It works now. And I wrote this in one conf file not two.
Options Indexes FollowSymLinks MultiViews
allow from all
Alias /iredadmin/static "/opt/www/iredadmin/static/"
WSGIScriptAlias /iredadmin "/opt/www/iredadmin/iredadmin.py/"
Alias /mail "/opt/www/roundcubemail/"
ProxyPass /Microsoft-Server-ActiveSync http://127.0.0.1:20000/SOGo/Microsoft-Server-ActiveSync retry=60 connectiontimeout=5 timeout=3540
ProxyPass /SOGo http://127.0.0.1:20000/SOGo retry=0
Alias /awstats/icon "/usr/share/awstats/icon/"
Alias /awstatsicon "/usr/share/awstats/icon/"
ScriptAlias /awstats "/usr/lib/cgi-bin/"
BTW, this is the third time I have reinstalled iRedMail. Not interested in doing that everytime there is a problem.