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RE: Moving database from HP to IBM-AIX

From: Goulet, Dick <DGoulet_at_vicr.com>
Date: Fri, 28 Oct 2005 12:16:34 -0400
Message-ID: <4001DEAF7DF9BD498B58B45051FBEA6502E09D77@25exch1.vicorpower.vicr.com>


Sandeep,

        If you want to use Pro*C you can have multiple connections to multiple databases at one time and use array processing. The problem is that your program will be peculiar to the application.

-----Original Message-----
From: oracle-l-bounce_at_freelists.org
[mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Sandeep Dubey Sent: Friday, October 28, 2005 12:02 PM
To: Mark W. Farnham
Cc: oracle-l_at_freelists.org
Subject: Re: Moving database from HP to IBM-AIX

Mark,

Thanks for the reply.

I am thinking on ways to optimize data unloading and transfering.

  1. Is it possible to use pipe so that as data is unloaded from source table, ftped and is consumed by sqlloader to pump in?
  2. Is there any faster tool to unload the data from table to flat file. Will Pro C be faster than sqlplus spool?
  3. How big should I have a flat data file. 4 GB enough or I can have bigger file size.?
  4. How best to use parallel processing?

Thanks again

Sandeep

On 10/28/05, Mark W. Farnham <mwf_at_rsiz.com> wrote:
> This is usually a balancing act between "death by details" and
parallelism
> on re-creation of indexes on your largest objects. It is very good
that you
> know your target window, so you can execute a test with a minimum of
effort
> an see if that is good enough.
>
> If the full export/full import runs in under 24 hours, why worker
harder?
> Unless you're running a MAID disk farm you probably don't even save
any
> electricity.
>
> Let's assume for the moment though, that is not fast enough.
>
> I'm not sure whether you have a full clone testbed of your warehouse
from
> which to get a testing source, but even if you don't, getting a dump
of what
> is for testing will be well worth a short additional outage so you can
test.
> Interim changes for a warehouse between the test runs and the real cut
over
> should not be material.
>
> So, you get a full no-rows export for starters. Get the data exports
by user
> and/or by user/table leaving out the big ones. Generate create table,
index,
> trigger and constraint scripts for the big ones.
> Unload the data from the big ones in a format that loader will swallow
well.
> Consider whether there is a predominant order of access supported by
an
> index for any of these big guys that might be worth the trouble to
reorder,
> and if there are any serious outliers and especially with partitioning
that
> you could load in parallel, you might want to also unload in pieces.
You
> said warehouse, so I'm guessing your rows no longer change in length,
so if
> you're not already aggressive with percent free you might want to get
> aggressive with a small percent free. If older stuff is row length
stable
> and younger stuff is not, consider unloading pieces by age so you can
load
> the older stuff denser and then adjust percent free for the younger
stuff.
> You *may* benefit from ordering the unload if there is either a
significant
> pattern of access that will cause corelation between block selectivity
and
> row selectivity in future use of the database, or if it will allow you
to
> build an index using the already sorted option.
>
> Run the no-rows import. Muck around and disable what you need to so
you can
> start the big boys loading in parallel streams (separate runs of
sqlloader
> to a reasonable load average on your CPUs rather than parallelism in
Oracle,
> so you don't pay the slave co-ordination overhead). As each big boy
> finishes, and taking into account max IOPs on your temporary space and
a
> reasonable load average on your CPUs, start indexing it. Again, you
probably
> win by multiple sqlplus sessions over parallelism.
>
> Good luck, and don't do more work than you have to.
>
> ------------------------------------
> Rightsizing, Inc.
> Mark W. Farnham
> President
> mwf_at_rsiz.com
> 36 West Street
> Lebanon, NH 03766-1239
> tel: (603) 448-1803
> ------------------------------------
>
>
> -----Original Message-----
> From: oracle-l-bounce_at_freelists.org
> [mailto:oracle-l-bounce_at_freelists.org]On Behalf Of Sandeep Dubey
> Sent: Friday, October 28, 2005 10:41 AM
> To: oracle-l_at_freelists.org
> Subject: Moving database from HP to IBM-AIX
>
>
> Hi,
>
> We need to move 2 TB data warehouse on Oracle 9.2 HP to Oracle 9.2
> database on AIX. These operating systems has opposite endian. Down
> time should be less than 24 hrs.
>
> Please let me know what will be faster and optimum way to do this. I
> am thinking of sqlloader as the fastest way to go. Are there any
> better alternative?
>
> If you have undergone such exercise please share your lesson learnt.
>
> Regards
>
> Sandeep
> --
> http://www.freelists.org/webpage/oracle-l
>
>
>
>
>

--
http://www.freelists.org/webpage/oracle-l


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Received on Fri Oct 28 2005 - 11:20:04 CDT

Original text of this message

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