Обсуждение: SMP support? Yes or no

Hi

I have an online application using postgres 6.5.3 (latest from stable
debian) and php3.

I'm not using many features (basically just tables and indexes).

The application (where teachers can grade their students) has already
been tested withou major hassle (at the time on a postgres 6.3.2 db).
The application was ported to a new machine where (besides the postgres
version) the only major difference is the fact that the new server has
two processors. Is postgres smp aware or not? Is it compiled by default
on debian (this one is for Oliver Elphick, the debian postgres package
maintainer).

The problem is like this: I have a table or i check if there is a record
with determined number of conditions, if there is i continue to use that
record has a pointer to other table so that I can perform my stuff. This
worked previously, but now i'm getting several record under the very
same conditions (they should be unique, but no i can't have a primary
key on them).

One thing that i've tried in the mean while (but for wich i don't have
any feedback yet) is turning fsync on.

Hope you can shed some light on this.

Thanks


--
        Mario Filipe
        mjnf@uevora.pt
        http://neptuno.sc.uevora.pt/~mjnf

Mario Jorge Nunes Filipe <mjnf@uevora.pt> wrote:
>Is postgres smp aware or not?

AFAIK, PostgreSQL is not explicitly SMP-aware, but given that a separate
backend server (postmaster) is started for each database connection, it will
take advantage of SMP automatically when there is more than one simultaneous
database connection.

>The problem is like this: I have a table or i check if there is a record
>with determined number of conditions, if there is i continue to use that
>record has a pointer to other table so that I can perform my stuff. This
>worked previously, but now i'm getting several record under the very same
>conditions

I strongly doubt this is SMP-related. I've been using PostgreSQL (7.0.3
recompiled for Debian potato) on several SMP machines without any unexpected
behaviour whatsoever.

HTH,
Ray
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