Oracle FAQ Your Portal to the Oracle Knowledge Grid
HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US
 

Home -> Community -> Mailing Lists -> Oracle-L -> Re: Capacity Planning

Re: Capacity Planning

From: LiShan Cheng <exriscer_at_gmail.com>
Date: Thu, 23 Feb 2006 14:35:09 +0100
Message-ID: <6e9345580602230535k3519fa13y1e0344be77cea59e@mail.gmail.com>


Hi

My boss at HP told me that his project, i.e mine is to migrate customers platform and not tune their application. Sort of correct if considering you have a deadline.

Life is not simple nor easy! :-)

On 2/23/06, Jurijs Velikanovs <j.velikanovs_at_gmail.com> wrote:
>
> > I did tune a bit the application. I was not allowed to tune too much
> because
> > my job was migration and not tuning. Basically a Data Mart was killing
> the
> > server. There were 2 instances running in the server.
> MIGRATION & not TUNING project
> I love this world ;)
> .
> Instead of spending MB$ for buying huge HW, people can just spend a
> bit of time to look inside that is going there and then make a
> decision what to do next.
> .
> You can't just copy DB from one platform to another (before 10G and
> transferable database). It is obvious you done export/import think.
> The physical layout has been changes, the statistics has been changed,
> Oracle code has been changed (not always Oracle code behaviors the
> same way on different platforms even if you managed get the same level
> of patching). By my mind tuning or/and a performance diagnostic or/and
> monitoring phases have to be part of a MIGRATION project.
>
> I would say MIGRATION includes TUNING :)
>
> J.
>
>
> On 2/23/06, LiShan Cheng <exriscer_at_gmail.com> wrote:
> > Hi
> >
> > They were custom applications. PL/SQL, Forms, Reports.
> >
> > We migrated from Sun Solaris to HP-UX. The HP guy took Sun CPU clock
> speed
> > and turned that in HP-UX Itanium CPU clock speed. Mathematics basically.
> For
> > example
> >
> > if Itanium CPU is twice as fast as a Sparc CPU, if the Sparc has a clock
> > speed of 400 Mhz and Itanium has 800 Mhz then 8 Sparc CPU is equivalent
> to
> >
> > 400 * 8 = 3200
> >
> > 3200 / 2 / 8 = 2
> >
> > i.e 2 Itanium 800MHz CPU were equivalent to 8 400MHz Sparc CPU. I was
> amused
> > but hey he was the expert not me! :-)
> >
> > I did tune a bit the application. I was not allowed to tune too much
> because
> > my job was migration and not tuning. Basically a Data Mart was killing
> the
> > server. There were 2 instances running in the server.
> >
> >
> > Cheers
> >
> >
> > --
> > LSC
> >
> >
> >
> >
> > On 2/23/06, Jurijs Velikanovs <j.velikanovs_at_gmail.com> wrote:
> > > > In my last project for example, a HP guy estimated 12 CPUs for a
> server
> > > > however in the practice we almost doubled otherwise the server would
> be
> > CPU
> > > > bounded.
> > > What kind of application we are token about? Is it custom made?
> > > Have you tried to tune performance of the application before doubling
> > resources?
> > > Was is RISC or Intel based server?
> > > Was it TOP SQL(-s) which consumed 90% of CPU?
> > >
> > > Jurijs
> > >
> > > On 2/23/06, LiShan Cheng <exriscer_at_gmail.com> wrote:
> > > > Hi
> > > >
> > > > Thanks for the reply.
> > > >
> > > > I am quite lost in this area basically becase I am quite reluctant
> about
> > > > capacity planning since I have seen quite a few and I have seen cero
> > > > success. Many times I would really like to ask the guy who did the
> plan
> > how
> > > > he did it without knowing so many factors.
> > > >
> > > > In my last project for example, a HP guy estimated 12 CPUs for a
> server
> > > > however in the practice we almost doubled otherwise the server would
> be
> > CPU
> > > > bounded.
> > > >
> > > > I understand it is necessary but... whose job should it be? DBA?
> > Hardware
> > > > Vendor? Software Maker? System Admin? Mix of all is probably the
> answer
> > but
> > > > then what information is needed by a DBA to perform such job?
> > > >
> > > > Shall I tkprof 10 sessions get the cpu time and multiply by the real
> > number
> > > > of users I will have? :-)
> > > >
> > > > Cheers
> > > >
> > > > --
> > > > LSC
> > > >
> > > >
> > > >
> > > >
> > > > On 2/23/06, Jurijs Velikanovs <j.velikanovs_at_gmail.com > wrote:
> > > > > I'm interested in that question as well. I believe almost all
> DBA-s
> > > > > had, have, will have to answer it.
> > > > > The most difficult for me was CPU power, I/O throughput and Memory
> > > > > planning for home made (custom development) applications
> > > > > .
> > > > > By my experience you can spend tremendous amount of time (not just
> > > > > yours time) creating capacity plan for a particular system during
> an
> > > > > application development time. Work with analysts, designers,
> > > > > developers documenting detailed calculations and all assumptions.
> But
> > > > > end of the day you will get, a +/- 50% accurate result ;).
> > > > > If at the end the applications will not perform well enough the
> > > > > Developers will blame HW and will some think like "You need double
> HW
> > > > > resources to get XX sec response time". DBA-s and Admins would say
> "We
> > > > > already have some thing like top HW". It is always difficult to
> say if
> > > > > developers have done their work well without knowing the
> applications
> > > > > business.
> > > > > .
> > > > > At the moment I think that most effective way to plan that type of
> > > > > capacity is make assumptions based on you or others project
> members'
> > > > > previous experience.
> > > > > - If in the past you have worked with kind of systems you
> currently
> > > > > developing you know already the most important parts of
> application
> > > > > you have to pay attentions. This is there you have to concentrate
> your
> > > > > attention. In most cases it is something like 2% of overall
> > > > > application code. Describe, prototype, play with that bit and of
> the
> > > > > day you will get -/+ 10% accurate planning.
> > > > > - If in the past you have worked with much bigger systems, with
> huge
> > > > > amount of data processing you can think like. This system is 5
> times
> > > > > smaller the system I have worked with. Presumably this system will
> run
> > > > > successfully on 2-3 times smaller HW and we will spend 2 times
> less
> > > > > time to tune it.
> > > > > - If you have chance to get information about system like you are
> > > > > going to implement (like OEBS, SAP, or other pre developed
> > > > > application, or the same functional application, or old system you
> > > > > going to replace), you can base your assumption on that
> information.
> > > > > .
> > > > > Later on then Developers will say you haven't enough HW capacity,
> you
> > > > > would be able to base you conclusion on a comparison of the
> developed
> > > > > application and other systems.
> > > > > .
> > > > > I don't think this approach is ideal, but at the moment I haven't
> > found
> > > > better.
> > > > > I would be glad to hear others opinion.
> > > > >
> > > > > Thank you in advance,
> > > > > Jurijs
> > > > >
> > > > >
> > > > > On 2/23/06, LiShan Cheng < exriscer_at_gmail.com> wrote:
> > > > > > Hi
> > > > > >
> > > > > > I was wondering if anyone know any source about effective Oracle
> > RDBMS
> > > > > > Capacity Planning. I mean effective because in the past I have
> seen
> > many
> > > > so
> > > > > > called "Capacity Plan" which failed miserably in the practice. I
> am
> > not
> > > > sure
> > > > > > how can a DBA perform Capacity Planning without knowing much
> about
> > the
> > > > > > application?
> > > > > >
> > > > > > Cheers
> > > > > >
> > > > > >
> > > > > > LSC
> > > > > >
> > > > > >
> > > > >
> > > > >
> > > > > --
> > > > > Jurijs
> > > > > +44 7738 013090 (GMT)
> > > > > ============================================
> > > > > http://otn.oracle.com/ocm/jvelikanovs.html
> > > > >
> > > >
> > > >
> > >
> > >
> > > --
> > > Jurijs
> > > +44 7738 013090 (GMT)
> > > ============================================
> > > http://otn.oracle.com/ocm/jvelikanovs.html
> > >
> >
> >
>
>
> --
> Jurijs
> +44 7738 013090 (GMT)
> ============================================
> http://otn.oracle.com/ocm/jvelikanovs.html
>

--
http://www.freelists.org/webpage/oracle-l
Received on Thu Feb 23 2006 - 07:35:09 CST

Original text of this message

HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US