We have ArcSDE 9.3 on Oracle 10g Windows 2003 32 bit box.
The same SDE is used by AGS 10 installation on Windows 2008 64 bit box.
Adding new services to AGS caused Maximum connections exceeded SDE error (we need 68 connections instead of default 48).
I increased maximum connections number by sdeconfig but then (as it was predicted by some posts) I ran into Oracle problems, ORA-12640 (Authentication adapter initialisation failed).
Our DBA checked the DB and said that Oracle problems are caused by SDE overload. Indeed, after restarting the SDE service everything works for some time.
Trying to reduce overload, I switched AGS services to Direct Connect.
I still see connections in sdemon since as Jake Skinner explained in his answer below, sdemon counts direct connections also.
The question is: should I expect reduce in SDE overload because of switching to Direct Connect.
As I know, with Direct Connect spatial procedures are made at the client (in my case - AGS box which is more powerful).
P.S. ArcSDE 9.3 is used for compatibility with another older GIS reasons.
Thanks in advance,