Specific User Trace and multiple radiusd instant

[Alan DeKok]

Fajar A. Nugraha wrote:
> Interesting idea. So use the number of db threads to somewhat limit
> max number of server threads used for accounting?

  Yes.

> In our implementation we ended up going with decoupled accounting
> instead, which pretty much serialize accounting load to db to the
> number of detail file and reader.

  That helps for systems like MySQL.  It doesn't handle parallel writes
very well.

>>  On top of that, the server prioritizes authentication internally.  It
>> will preferentially process authentication packets over accounting
>> packets.  So that's one more way to avoid server meltdown.
> 
> Is this code new?

  No.  It's in 2.1.x.

> I haven't seen that effect back on our old setup (the days of
> FR-2.1.7). But then again there might be other factors causing it.

  It's not immediately visible when you use the server.  The code just
prioritizes processing auth over acct.  So if it receives a lot of
accounting packets, it will "starve" them, and process authentication
instead.

  This only happens when it's overloaded, so it's unusual, and difficult
to see.

  Alan DeKok.