Re: session servers in ram

Alan Hodgson wrote:
> On Monday 21 September 2009, Scott Marlowe <scott(dot)marlowe(at)gmail(dot)com> wrote:
>> I'm looking at running session servers in ram.
>
> Use memcached for session data.

IMHO postgres is more appropriate for some types of session data.

One of the apps I work on involves session data that consists of
geospatial data which we store and index in postgres/postgis.

Scott Marlowe wrote:
> I'm looking at running session servers in ram.
> We're currently IO write bound with
> fsync=off using a 15k5 seagate SAS drive, so I'm hoping that moving
> the db into /dev/shm will help quite a bit here.

"a 15k5 seagate SAS drive"

Is this implying that you have "a" == one session server? I
bet that it'd be cheaper to throw a bunch of cheap boxes
in there and make a pool of session servers rather than one
fast one. When a new session is created, your application
code can then pick the least loaded session server and put
the session-server-number in a cookie.

This approach works fine for me - but I suspect I have many
fewer, yet probably much larger sessions going through the
system.

> Does anybody any real world experience here or any words of sage
> advice before I go off and start testing this?
>