On Wed, 14 Jul 2010, Ivan Voras wrote:
Returning 8449 rows could be quite long.
You are right, I didn't test this. Issuing a query which returns a
smaller result set is much faster.
But, offtopic, why would returning 8500 records, each around 100 bytes
long so around 8.5 MB, over local unix sockets, be so slow? The machine
in question has a sustained memory bendwidth of nearly 10 GB/s. Does
PostgreSQL spend much time marshalling the data through the socket stream?
It's disk access time.
in the very bad case it could take ~5 ms (for fast drive) to get one just
one row.
Regards,
Oleg
_____________________________________________________________
Oleg Bartunov, Research Scientist, Head of AstroNet (www.astronet.ru),
Sternberg Astronomical Institute, Moscow University, Russia
Internet: oleg@xxxxxxxxxx, http://www.sai.msu.su/~megera/
phone: +007(495)939-16-83, +007(495)939-23-83
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