Re: Parralelizing Oracle processes

Interestingly the text in the sample init.ora Oracle provides says: "Typically two parallel process per CPU provides good performance. However for systems with a smaller number of CPUs, more parallel processes may be desired.

Well I have one CP on my notebook so theoretically I should conclude that I can set parallel_threads_per_cpu = 4.

I wonder what the Oracle folks would say about that. <g>

Daniel Morgan

RSH wrote:

> Frederic,
>
> you have to tell Oracle what operations you want "parallellized" <- cringing
> at that word.
>
> There are many places and different ways to let Oracle know this; none of
> this is of much use to you if you are not working on a multiprocessor
> system, and of dubious benefit to you if you do not have enough disk space
> (in spindles, or drives) to spread certain things out, and enough available
> memory to accomodate a larger Oracle SGA and to help buffer these
> operations.
>
> Thank goodness it defaults to none instead of presuming what you might want!
>
> For example:
>
> If you have large SQL*LOADER loads from flat files into Oracle tables to do,
> you might set up to break the input file into several different pieces on
> different drives, create a SQL*Loader script that includes DIRECT, PARALLEL,
> etc; all that stuff is in the Oracle Utilities Reference Manual. (It's in
> English, sort of.)
>
> Or, if you have say a massive flat table that needs to be processed either
> for derivative processing (like in a data warehouse) or is frequently
> involved in full table scans, you might wish to (say it's a 4 GB table and
> overhead and change) create a tablespace to house that table that is
> composed of 4 1 Gb datafiles, each on a different drive, and precreate and
> allocate that space before you SQL*LOAD the table, and of course, never DROP
> it, but if appropriate, only TRUNCATE it if you wish you empty it out
> completely.
>
> In this case, supposing you have an 8 processor SMP (symmetrical
> multiprocessor) system, CREATEing, or ALTERing that table to have a DEGREE
> of 4, supposing you have enough CPU and memory, could greatly help.
>
> RSH.
> "Frederic Payant" <fpayant_at_club-internet.fr> wrote in message
> news:bur8cus0c9gvhtu61q9gauk4khs0o6v1qm_at_4ax.com...
> > Hi,
> >
> > I've a little problem with Oracle 817 on Solaris : Is it parallel. I
> > mean : all documentation, about orders, packages, init files seems to
> > meet the idea that, by default, Oracle always parallelize operations,
> > big scans, statistics and so on.
> > But when I launch large jobs or stats, I very well see that these jobs
> > are all done by one single processor (I currently work on a 8 procs
> > domain).
> > Did I miss something in doc; Must I set any parameter ? Is it becaus I
> > use a 32bits version of Oracle ?
> >
> > Any info will be welcome (and don't hesitate to ask me any further
> > information if needed)
> >
> > Thanks a lot
> >
> > Regards
> > Frederic PAYANT - junior DBA ;-)
Received on Mon Apr 22 2002 - 17:56:26 CDT