[Deploying Sakai] Deployment sizing question

[R.P. Aditya]

Hi Todd,

Here's how we (University of Michigan) deal with the issues you bring up:

In gmane.comp.cms.sakai.production, you wrote:
> What methods and metrics are people using to asses how many application 
> servers will be necessary?

we've found that appservers are not cpu bound, and now with 64-bit machines
and 6GB heaps are not memory bound -- for our load, we have 5 appservers and
they are overkill, though they are necessary to spread the risk of Sakai going
unresponsive (for many different known and yet-to-be-determined reasons)

you can see our load at:

  http://tinyurl.com/ctstats

let me know if you need more specifics

> What network load balancers are being used to distribute load across 
> their application clusters?

We use Netscalers

> What methods are being used for node affinity within the load balancer? 
>   ie. stickytimes, cbr/cookie persistence, something else?

cookie persistence and backup with sourceip for clients that don't send
cookies (ie. Webdav)

> Has anyone implemented Oracle RAC in support of their Sakai system?

we tried it in our development environment and determined it was more complex
than we wanted and it didn't buy us enough (we couldn't figure out transparent
jdbc failover with the oracle thin client)

> Has Oracle 11g been successfully implemented as the backend for Sakai?

we have successfully run our load-test environment against 11g and are
planning to upgrade to it in production this calendar year

Thanks,
Adi