Re: ODBC Performance slow for large results

(2011/06/19 11:06), Ramesh Reddy wrote:
> Hi,
>
> I am not using "UseDeclareFetch" and using "UseServerSidePrepare=1", but
> we see over 40 mins for fetching over million rows between couple
> powerful machines. Debug/trace is not in use either. I am using Redhat
> Linux machines for both server and client. I am using prepare
> statements. I using a small perl utility for testing, but results are
> same with isql too.
>
> I have read though the ODBC code, couple things I observed was
>
> 1) All the tuples from the server are pre-fetched before a single row is
> returned to user. So, million rows are fetched to driver first (I was
> not sure whether these are all memory resident or written to temp disk
> space). So can somebody comment on memory implications? I see this
> operation is completed fairly quickly, noting the fact that PG server is
> responsive in returning and no network delays seen. We are also ran
> independent tests to make sure we are running in full duplex.
>
> 2) From the debug logs, we seen significant time spent on "copy and
> convert" operation, where the text response from PG server is being
> converted to respective data types.

Could you send me directly the part of Mylog output?

regards,
Hiroshi Inoue

 > Is there any way I can configure PG
> database and ODBC driver to return the data in "binary" format, to
> minimize this step? I do see CPU utilization being pegged during
> operation.
>
> Any way to re-compile *may be* to make both 1&  2 above occur in
> parallel to minimize times? Or any other techniques any one can suggest,
> I would really appreciate it.
>
> Thank you in advance for any advise you can share.
>
> Ramesh..