db performance

[A.L.M.Buxey at lboro.ac.uk]

Hi,

> Yep. Last "production" load test I did was with Postgresql 7.x, FreeRADIUS 
> 1.0 and my pgsql-voip.conf was on a 4GB table and I was happily pushing a 
> steady 800 Accounting requests per second on a single CPU P4 3.0 desktop 
> machine with a single 7200rpm PATA disk. This was around 5 years ago.

5 years ago...Pentium 4. hmmm. that would have been the rather poor
Northwood P4 processor too - several functions missing from the core, small
L2 cache and slow FSB.

> My current production servers are single Opteron CPU SunFire 2100 machines 
> with SATA disks. The backend DBs are the same. The RADIUS boxes never break 
> 3% CPU load. The Postgresql servers are IO bound by the SATA disks....

dirty thought....if these are mainly queries then you *could* do the
following (depending on memory and table size).... simpyl create a
4Gb tmpfs partition and use that for the database - with the real
disk-based database being a synchronized DB. 

> Basically on a properly designed DB server, with the correct indexes for your 
> data you are always going to be IO bound for any type of RADIUS requests 
> that dont involve EAP (expensive crypto operations)

...and even those *might* be offloaded onto an SSL crypto acceleration card

alan