Обсуждение: Re: PostgreSQL on Cygwin

Terry,

[Sorry for the sluggish response time -- those pesky holidays and
vacations are always getting in the way...]

On Thu, Jul 05, 2001 at 09:11:09PM +0000, Terry Carlin wrote:
> On 7/4/01, 3:31:37 PM, Jason.Tishler@dothill.com (Jason Tishler) wrote
> regarding Re: PostgreSQL on Cygwin:
>
> > On Tue, Jul 03, 2001 at 09:08:09PM +0000, Terry Carlin wrote:
> > > I posted this message on the postgresql.ports.cygwin list and have not
> > > heard anything from anybody.  Tom Lane suggested that I contact you
> > > directly with this problem.
>
> > I monitor the pgsql-cygwin@postgresql.org mailing list very closely
> > and I did not see any of your posts.  To what mailing list does
> > "postgresql.ports.cygwin" correspond?
>
> I don't subscribe to the mailing list, I posted to
> comp.databases.postgresql.ports.cygwin news group.

My guess is that comp.databases.postgresql.ports.cygwin is tied to
pgsql-cygwin@postgresql.org and vice versa, but it appears that messages
get lost between the two occasionally.

Given your current role, I would recommend subscribing to pgsql-ports
and pgsql-cygwin -- the traffic is fairly light.

> > My WAG is that you have found a Cygwin resource leak -- my best guess is
> > open handles.  Since the activity of a benchmark application is by its
> > very nature intensive and "long lived" as compared to someone typing
> > away at bash, it would be much more likely for you to stumble over a
> > resource leak than the typical Cygwin user.
>
> This is why I was running the benchmarks against PostgreSQL on CYGWIN.
>
> > Try adding more columns (e.g, Handle Count) in Task Manager to determine
> > whether or not my hypothesis is correct.  Another option is to use
> > Performance Monitor.
>
> I added the Handle Count to the Task Manager and found some interesting
> stuff.  These are the memory and handle statistics from this run.
>
> This machine has 256 mb ram
> PostgreSQL Memory size Process 1 6,632k, # of handles 756,889
> PostgreSQL Memory size Process 2 6,636k, # of handles 474,435
> PostgreSQL Memory size Process 3 6,640k, # of handles 247,353
> PostgreSQL Memory size Process 4 6,632k, # of handles 56,515
> Does look like we ran out of handles

I would like to reproduce your resource leak problem without using
Benchmark Factory.  Can you suggest a way to "emulate" your testing by
driving psql or using JDBC?  If I can reproduce the problem, then I may
be able to plug the leak.  If so, then I will submit a patch to Cygwin
for consideration.  Otherwise, I can post a hopefully minimal test case
that demonstrates the problem to the core Cygwin developers.

Thanks,
Jason

--
Jason Tishler
Director, Software Engineering       Phone: 732.264.8770 x235
Dot Hill Systems Corp.               Fax:   732.264.8798
82 Bethany Road, Suite 7             Email: Jason.Tishler@dothill.com
Hazlet, NJ 07730 USA                 WWW:   http://www.dothill.com

Cygwin folks,

My database calls seem to be VERY slow---10 seconds for a single
query that returns a handful of records.

"select version()" yields:

 PostgreSQL 7.1.2 on i686-pc-cygwin, compiled by GCC 2.95.3-4

I am actually running to ASP pages but calls via Access seem
to be having the same problem.  However, typing the same queries
into the psql interpreter generates snappy responses.

So, my question is: is this just the nature of the beast? Is
there probably a particular layer (ipc-daemon, odbc driver,
or otherwise) which is particularly at fault? Has anyone else
experienced this issue?

Thanks in advance.

-Robby Slaughter