Thanks for your replies.
I know that radacct is not used for authentication but, its rows contains information (Seconds) to the counters (To allow or not start a session).
So, my problem is that I have all rows in only one table, without historical data. The server is working with NAS (Disk cabin), for this reason sharding and partitioning techniques I think that there are not necessary.
Do you know if are there some technique to implement or if FreeRADIUS allows to work with more than one radacct table?
Thanks in advance.
Regards,
Antonio.