Re: Import performance.

From: Linda Montgomery <montgolh_at_jmu.edu>
Date: Wed, 21 Oct 1998 14:58:55 -0400
Message-ID: <362E2EEE.393268A3@jmu.edu>

There are several changes we make to increase import speeds. Here is our little checklist of things to check/change before a big import. Afterwards we put everything back like it was.
1. Make sure redo logs are large enough & that there are enough groups. Try to keep log switches at least 3 minutes or more apart. We have been increasing logfile size to 30M minumum ( a size that worked for our environment) if smaller than that in production.
2. Place each logfile on a seperate drive (or ping pong between drives) to eliminate contention.

3. Set db writers =  # of disk drives * 2
4. Set init.ora parameter checkpoint_process = true
5. Verify log_simultaneous_copies is corret for  the # of processors, or remove

parameter if on a single cpu machine.
6. Check for adequete rollback & temp tablespace sizes & that their initial & next extent will allow them to grow to the maximum value. 7.Be sure to use commit=y for large tables 8. Increase size of init.ora parameter log_buffer to 1,024,000

Linda
montgolh_at_jmu.edu

MotoX wrote:

> Correct, only EXPORT supports DIRECT.
>
> And remember to take a *backup* after recreation of the indexes, unless you
> want to go through the whole procedure again should you suffer media
> failure...
>
> MotoX.
>
> Murali Kazhipurath wrote in message <362d879c.0_at_blushng.jps.net>...
> >From what I have understood, DIRECT PATH only works with EXPORT. Here are a
> >few tips:
> >
> >1. Drop all Indexes.
> >2. Import without indexes using the option indexes=n.
> >3. Rebuild indexes using the UNRECOVERABLE option.
> >
> >Hope this helps.
> >
> >Murali
> >murali_at_jps.net
> >
> >
> >xsun1913_at_my-dejanews.com wrote in message
> ><70ilit$2j0$1_at_nnrp1.dejanews.com>...
> >>In article <01bdf5d0$fabc77a0$5feaabc3_at_ken-bailey>,
> >> "Ken Bailey" <Ken.Bailey_at_BLAENAU_GWENT.btinternet.com> wrote:
> >>> Can anyone give me any guidelines on improving import performace (
> >>> parameters etc) ?
> >>>
> >>>
> >>
> >>Use DIRECT PATH when running import; Set buffer to a large number.
> >>
> >>
> >>Xuening Sun
> >>
> >>
> >>
> >>-----------== Posted via Deja News, The Discussion Network ==----------
> >>http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own
> >
> >
Received on Wed Oct 21 1998 - 13:58:55 CDT