Re: Resource Manager on 8i: an underestimated tool or what ?

"Nuno Souto" <nsouto_at_optushome.com.au> wrote in message news:dd5cc559.0210271730.4b602ff3_at_posting.google.com...
> "Howard J. Rogers" <howardjr2000_at_yahoo.com.au> wrote in message
news:<0DOu9.63414$g9.177683_at_newsfeeds.bigpond.com>...
> >snip...
> > All anecdotal, of course.... Point being, if you get into developing
fancy
> > plans, it can all end up being sufficient rope with which to hang
yourself.
> >
>
> I think the problem is that many have considered RM as some form of
> performance 'fix-it'. Which it isn't. In fact, a good way of ensuring
> a slow job will run even slower is to use the RM. It won't fix a bad
> plan. What it will do is stop that job from killing the system
> for everybody else. That is not bad but may be not what people
> expect it to do.
>
> > Actually, if you had 9i, I'd consider it worth investigating for its
ability
> > not to start jobs the optimiser predicts will take too long.
> >
>
> Yup, my feelings too. 8i is a bit 'raw' in this area...
>
> Cheers
> Nuno Souto
> nsouto_at_optusnet.com.au.nospam

Thanks for the reply Nuno, actually I've seen there is some overhead when using the RM, but on the other hand it seems to work fairly smoothly in my case.
I need to ensure that a certain group of users don't choke the system while more important task are being carried out and this is exactly what the RM does for me (at least in the test environment!). Certainly I am not going to design a very sophisticated plan, just a simple one, similar to the oracle provided system_plan, where a certain group of users running business critical procedures is entitled to use more CPU than users running batch programs or queries.
I was also interested in knowing whether anybody had experience with priority level assignment, for instance, I left system_group at level 1 with a 100% CPU allocation, is this a good practice or what? I've seen plans where the system_group is absent, is that a good idea? I thought it would be always better to reserve some CPU for a system session, just in case, in the end its CPU allowance is devolved to the next level if it not used, isn't it?

Bye,
Flavio Received on Mon Oct 28 2002 - 07:28:36 CST