Re: Oracle 8i and ESMA

Hi,
Thanks for your insights. First things first, the block size is 8K. We have a large database (several million records over 3/4 GB). The notion is if all the records are in DB Buffers, the query performance improves. On top of it, if 8GB RAM is available, and there is a way to use all of it, why not try it. Can a two-bit contractor DBA(me) gainsay it, hit ratios or no hit ratios?
TIA,
In article <972737847.11771.1.pluto.d4ee154e_at_news.demon.nl>,   "Sybrand Bakker" <postbus_at_sybrandb.demon.nl> wrote:
> Increasing db_block_buffers should be based on measuring the hitrate
 by
> running ultbstat and utlestat.
> Bumping up db_block_buffers indiscriminatly is not going help, it will
 only
> increase paging activities, making your loose any gain.
> As a general guideline the total SGA should not be bigger than about
 one
> third of physical memory, so in your case 2.3 G.
> More than 256k db_block_buffers (regardless of block_size and you
 don't
> specify that one) is clearly outrageous, and it is not going to help
 you a
> damn, as for the last .1 percent hitrate increase you need
 extraordinary
> amounts of memories.
> I recommend measuring the hitrate first before you proceed. If it is
 above
> 95 percent, don't do anything to increase it, between 90 and 95
 percent it
> is questionable to anything.
>
> Hth,
>
> Sybrand Bakker, Oracle DBA
>
> <pvinnakota_at_my-deja.com> wrote in message
> news:8tcld2$5o6$1_at_nnrp1.deja.com...
> > Hi,
> > We installed Oracle 8i (8.1.6) on an NT server with 8GB RAM. Now we
 are
> > trying to increase the SGA size beyond 4GB using the guidelines in
 the
> > whitepaper on this subject. I followed the guidelines and made the
> > requisite modifications to the init.ora etc.
> >
> > In the process, we could ramp the SGA size up to 2.7GB by gradually
> > increasing the DB_BLOCK_BUFFERS. There was a gradual increase in
 the
> > SGA size from 623MB to 2.7GB. Once the the DB_BLOCK_BUFFERS number
> > crosses certain limit(256k), the size of the SGA is reverting to a
 very
> > small size (157MB).
> >
> > Has anyone tried this and succeeded? Please help with your
 insights.
> >
> > Thanks,
> >
> > Prasad V.,
> >
> >
> > Sent via Deja.com http://www.deja.com/
> > Before you buy.
>
>

Sent via Deja.com http://www.deja.com/
Before you buy. Received on Mon Oct 30 2000 - 09:10:40 CST