Re: Limit on connections

Thanks Jason

Just to let you know. I finally solved the Permission Denied problem
when the database was trying to
write to the transaction logs.

It was because of a nightly backup they were running on the machine. I
had asked them many times about
their tape backup system, but they told me they weren't backing up that
machine. Turns out they were.
I finally got a look at the backup logs and saw that every time the
machine went down, what was it doing,
the backup!

So now I scheduled pg_dump to run every night and they just back up the
one file. The machine is still up :-)

-----Original Message-----
From: Jason Tishler [mailto:jason(at)tishler(dot)net]
Sent: 25 February 2003 02:26
To: Colin Mangiagalli
Cc: pgsql-cygwin(at)postgresql(dot)org
Subject: Re: [CYGWIN] Limit on connections

Colin,

On Mon, Feb 24, 2003 at 03:54:14PM +0200, Colin Mangiagalli wrote:
> Is there a limit under postgresql/cygwin/windows to the maximum number

> of connections you can make to the database.

Yes, Cygwin has a limit of ~63 children per process (due to Cygwin's
fork() implementation). Hence, Cygwin PostgreSQL will have a similar
limit to the maximum number of database connections.

> I had this weird problem that there were about 35 connections open
> (looking at the windows task manager), all doing something (what I
> don't know) and the CPU usage was sitting at 100%

Time to debug. Attach via gdb or strace to determine what the spinners
are doing.

> What does that mean if the connections don't want to close normally?

Switch to Linux? :,)

> Is there a way to see what could have opened the connections?

Try the following:

http://www.sysinternals.com/ntw2k/source/tcpview.shtml

or one of the other great tools from Sysinternals.

Jason

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