Re: PostgreSQL 9.0 x64 bit pgbench TPC very low question?

My app has ~ 20 exe file, each of exe create new connect to postgesql and
there are 10-30 user use my application so I need -C to check PostgreSQL
performance.

I will test without -C option. But is there any way to decrease connect time
when there are 200 process, each of process will create new connect to
postgresql.

On Sun, Dec 19, 2010 at 1:51 AM, Jeff Janes <jeff(dot)janes(at)gmail(dot)com> wrote:

> On Sat, Dec 18, 2010 at 10:15 AM, tuanhoanganh <hatuan05(at)gmail(dot)com> wrote:
> > I have server computer install Windows 2008R2, PostgreSQL 9.0.1 64 bit,
> 8G
> ...
> > pgbench -h 127.0.0.1 -p 5433 -U postgres -c 100 -t 10 -C -s 10 pgbench
>
> Why the -C option? You are essentially benchmarking how fast you can
> make new connections to the database. Is that what you want to be
> benchmarking?
>
> If the code you anticipate using is really going to make and break
> connections between every query, you should use a connection pooler.
> Which means you should be benchmarking through the connection pooler,
> or just leave off the -C.
>
> Also, -t 10 is probably too small to get meaningful results.
>
> > tps = 20.143494 (including connections establishing)
> > tps = 256.630260 (excluding connections establishing)
> >
> > Why pgbench on my server is very low or is it common value with my server
> ?
>
> Starting a new connection in PG is relatively slow, especially so on
> Windows, because it involves starting and setting up a new process for
> each one.
>
> Cheers,
>
> Jeff
>