[Zope] PyGres DB Connection in Zope drops when many Users are added (UserDB) (UserDB)

[John D. Rowell]

On Tue, Apr 25, 2000 at 01:19:25AM -0500, Stephan Richter wrote:
> I use:
> Zope 2.1.4, PyGres 2.x, Apache, and PostGres 7.0RC1
> 
> The issue:
> It seems like that whenever "many" (10, I know that is not much) people 
> sign up at the same time on our Web Site (http://www.plandepot.com), we 
> loose the DB connection. The connection is simple restored, when 
> disconnecting and the reconnecting the database.
> Unfortunately I was unable to reproduce the error outside of business 
> hours, so I had never the chance to inspect the issue in detail. I 
> personally do not think it is PostGreSQL or Zope, since I would have read 
> more about it.
> I have to mention, that PyGres is not thread safe and by default Zope uses 
> more than one thread if required. So could that be the issue? How do I 
> setup Zope in a way, that it uses only one thread? Also, I do not use any 
> of the caching features in Zope SQL Methods either.

Hi Stephan,

I've been running a very similar setup for seven months now under a lot
heavier traffic, and have never experienced db connection drops
(although I've heard about people with similar problems). Maybe this is
an operating system or compilation issue. I'm using Linux 2.2.9 and have
compiled everything on the same development environment, especially the
ZPyGres part matches by running version of pgsql. This is running pgsql
6.5.3, I do have 7beta5 on my development machine but didn't make any
stress tests on it. On the other hand, Postgres itself can kill a
connection depending on how severe an error it encounters. Broken
indexes tend to do that. Try to run a "vacuum analyze verbose" daily, it
will check for index consistency and improve your overall db
performance. Another hint would be logging your standard_error_message
to a file, it usually contains verbose data from the pgsql driver when
there is an error.

Cheers,
jdrowell

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