Re: Capacity Planning

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
>

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