Re: how much cpu on a database rac cluster
Date: Wed, 5 Sep 2012 08:59:07 +0300
Message-ID: <MSB1s.26027$ck7.14590_at_uutiset.elisa.fi>
"Mladen Gogala" <gogala.mladen_at_gmail.com> wrote in message
news:pan.2012.08.27.02.24.45_at_gmail.com...
> On Sun, 26 Aug 2012 17:49:25 -0700, dshproperty wrote:
> and we said...
> o do I support this
>
> nope, not at all. One machine, one host - ONE INSTANCE
>
> --
> Mladen Gogala
> http://mgogala.freehostia.com
Well, I must say I totally disagree.
One machine, one host -TEN INSTANCE
That is called consolidating. (I am not talking about RAC).
When you have ten systems in ten host the next step is colsolidate those
into one host.
CPU consumption is quite similar with ten or one instance (the work does not
disabear), and you know cpu-power is cheaper than dedicated manpower.
Surely you will need more memory with ten than with one instance, but
hardware is very cheap,
comparing what it is used to be some years(decades) ago.
And very other there is different instance for very good reason.
We have been running single host with ten intance (very mission
critical/operational, but not vldb) many, many years.
Management is also simple/better when having control for one business-system
per instance.
And into first question:
>Our 3 nodes RAC cluster (Dell, 32 core, hosting 6 databases) is using about
>10 percent cpu during normal business hour. At peak, it use about 30% cpu.
>Did we allocate too much CPU on this box? We are investigating whether it
>is worth the risk of reducing CPU to save money
If your numbers are correct, you could easily test it shutting down one node. See what happens, if about 50% cpu load go for it. Received on Wed Sep 05 2012 - 00:59:07 CDT