Re: Which DB instance(among 2 running instances) is preferred with Oracle TAF feature?

K Gopalakrishnan wrote:
> Daniel:
>
> I think there was mis-understanding as I have not discussed the load
> balancing to the depth as the original poster just wanted to know from
> the tnsnames.ora level. That is why I had clarified him saying TAF is a
> feature from the network layer, not from the services layer and TNS
> load balancing is purely round robin. It does not care about CPU load
> or number of connections.
>
> To answer your question, you are commenting about listener load
> balancing where we register the CPU load to the other nodes (using
> remote listener) and do the load balancing based on the least loaded
> note. And also there is a way to disable that using an underscore
> parametetr (_prefer_least_loaded_node or something like that in
> listener.ora) as the listener load balancing does not perform
> effectively for benchmarks or logon storms.
>
> If you have the listener load balancing setup, the listeners cross
> register with other participating instances and update the cpu load in
> every 5 minutes. If you have all connections coming up with in 5
> minutes there are chances that all connections will go to the first
> identified node. I think that is what you have experiened and that is
> not based on numbers (10+ connections as you mention), but based on the
> CPU load during that time.
>
> There are couple of other load balancing options also available based
> on other network level parameters. But to answer your question,
> listener load balancing is based on machine load and client load
> balancing is based on round robin.
>
> Hope this clarifies this
>
> Best Regards,
> K Gopalakrishnan
> Co-Author: Oracle Wait Interface, Oracle Press 2004
> http://www.amazon.com/exec/obidos/tg/detail/-/007222729X/

I didn't know I was unclear about anything ... but thank you for clearing it up for the many others that may have been wondering what this was all about.

-- 
Daniel A. Morgan
http://www.psoug.org
damorgan_at_x.washington.edu
(replace x with u to respond)