Freeradius 3.0.7 and multiple buffered-sql servers - detail file issues

[Alan DeKok]

On Apr 17, 2015, at 3:23 PM, Rygl Aleš <ales at rygl.net> wrote:
> The goal is to have server which
> - responds as fast as possible.  
> - is resilient to occasional peaks in the accounting traffic with magnitude of 
> 10 or more
> - drops packets as little as possible 
> - utilizes parallel processing on the DB side as much as possible

  That's usually the goal. :)

> I was not able to reach this with InnoDB engine with just sigle queue. It was 
> pretty fast with MEMORY engine but it suffers from locking on table level (and 
> uses just a single connection to DB). I was affraid that talking to DB 
> directly (without fallback to a file buffer) would had problems in case of 
> peaks. So the idea behind is to rather write to a file which IHMO cheaper that 
> perform a DB transaction where I have to wait for a lock.

  Hmm... sounds like DB issues, to be honest.  Your other message mentioned 3-5s delay writing to the DB.  That should *never* happen.  A normal DB should be able to handle 200-1000 writes per second.

> I can confirm that it is definitely faster. I have followed Arran's 
> recomendations and reduced the number of queues to 12 and it looks good. I 
> will play with this more.

  That's good.  You should be able to do:

accounting {
	...
	redundant {
		sql
		detail
	}	
	...
}

  And carefully tune the "pool" parameters to the SQL module.  If all of the connections are in use, the server will fail-over to using the "detail" module.  This process is very quick, so there's no performance issues.

> I will try again. Actually I have two more virtual servers in the config with 
> a single queue processing just couple of packets per second and this error was 
> there too. I will do some debugs here.

  Maybe try the v3.0.x branch.  We'll turn it into 3.0.8 real soon now...

  Alan DeKok.