Remember that any data access component is riding on the underlying physical layer.
You need to make sure that your network infrastructure can pump that much data through it.
Are you network cards running in full duples or half duplex?
What sort of switching infrastructure do you have?
The vast majority of switches have a blocking architecture. In a heavy environment this will cause oversubscription which will result in congestion. If you are using a managed switch, your network admins will hopefully know how to troubleshoot and tell you if that is the case (they will see resends, etc.).

Just another area to look at.

> -----Original Message-----
> From: pgsql-odbc-owner@postgresql.org
> [mailtogsql-odbc-owner@postgresql.org] On Behalf Of Arnaud Lesauvage
> Sent: Thursday, October 19, 2006 8:24 AM
> To: Obe, Regina
> Cc: pgsql-odbc@postgresql.org
> Subject: Re: [ODBC] Improve ODBC Throughput ?
>
> Obe, Regina a écrit :
> > What kinds of indexes do you have on your tables? I think the way
> > Access works to limit transfer it first pulls the indexes
> and probably
> > the primary one first to determine how to fetch and how
> many to fetch.
> > I suspect if you have no indexes performance would be really bad.
> >
> > Also which version of psqlODBC driver are you using?
>
> I have integer primary keys on most tables, if not all of them.
> Even my views have an integer primary key (at least,
> something that can be used as an integer pkey in Access).
>
> My version of psqlODBC is 8.1.2.0.
>
> I forgot to mention something important : I obtain the best
> performances (500kB / sec, cf my first post) when I am NOT in access.
> In a VBA module (Autocad, not Access), I open an ADO
> connection to PostgreSQL and directly query the server (no
> linked table involved here). But still, this is "only"
> 500kB/sec...
>
>
>
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> subscribe-nomail command to majordomo@postgresql.org
> so that your
> message can get through to the mailing list cleanly
>

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TIP 4: Have you searched our list archives?

http://archives.postgresql.org

Benjamin Krajmalnik a écrit :
> Remember that any data access component is riding on the underlying physical layer.

Yes, but this network is fast. From the same server, file transfer
is using the full ethernet capacity (~10MB / second).


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TIP 2: Don't 'kill -9' the postmaster

Have you tried one of the systernals tools like ProcessExplorer
http://www.sysinternals.com/Utilitie...sExplorer.html

Or FileMonitor
http://www.sysinternals.com/Utilities/Filemon.html

To debug it.

Those often uncover all sorts of stupid little errors.

Thanks,
Regina

________________________________

From: Arnaud Lesauvage [mailto:thewild@freesurf.fr]
Sent: Thu 10/19/2006 1:13 PM
To: Benjamin Krajmalnik
Cc: Obe, Regina; pgsql-odbc@postgresql.org
Subject: Re: [ODBC] Improve ODBC Throughput ?



Benjamin Krajmalnik a écrit :

> Remember that any data access component is riding on the underlying physical layer.


Yes, but this network is fast. From the same server, file transfer
is using the full ethernet capacity (~10MB / second).






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