freeradius load and message handling

[liran kessel]

Hi,


we have a freeradius server collecting accounting events from a few Nokia GGSN’s and are storing them into the MySQL DB.

Now that we have activated all messages we are receiving around 20K messages a minute, and have started seeing these events in the radius.log

 Tue Jun 14 22:53:33 2016 : Info: WARNING: Please check the configuration file. 	The value for 'max_requests' is probably set too low.

it was originally set to 1024, when we increased it and set it to 4096 the amount of such events was reduced but still didn’t disappear. 
If we set it higher (6100 for  example) we start getting these errors

Tue Jun 14 21:30:02 2016 : Error: Received conflicting packet from client localhost port 41935 - ID: 200 due to unfinished request 192178.  Giving up on old request.

why does this event appear? what would be the best way to manage this situation?

The server has 8 Cores and 4GB of RAM. 
It seems that the CPU isn’t overly loaded, but our RAM is almost completely used by the Radius and Mysql processes.

Will adding RAM to this server help us?  or isn’t it the bottleneck for this issue?

Thanks 
Liran