Subject: a problem using Postgres on Suns

From: Carole Goble <[email-masked]>
Date: Thu, 18 Feb 93 18:39:31 -0800

Dear Postgres experts

We have recently installed Postgres on our Sun cluster for a number of
students to explore. We do, however, have a problem which we think is a
mistake in our install and we would appreciate some advice.

We are running the postmaster on a Sun Sparc 2 with 32 Mb memory.
We have thus installed the TTMOREIPCS in order to run more Postgres
backends. The clients are Sparcs.

We get this situation:

10+ students are running backends on their own databases using monitor.
They work for about an hour or so retrieving, defining functions etc..
Then they begin to fail on define statements, retrieves using user-defined
functions, replace and append statements. Straightforward retrieves 
continue to work. 

The error is that the postmaster has signalled an error to the backend
and terminated the backend unexpectedly. The user is returned to the unix prompt.
The backend is still running on the server however. A warning that shared memory
may be corrupted is also given. (sorry I haven't a copy of the exact wording here).
The error is NOT the complaint about the lack of shared memory warned of in the
manual.

Once this happens they all seem to collapse. An ipcclean helps for a short while,
as does rebooting the server.

If, however, a few (say 4) students use Postgres simultaneously it stays up
without a problem. 

Postgres is running on the same server as Oracle (no more space anywhere else!)
but no one is using Oracle when the Postgres users are on.

Thanking you in anticipation with kind regards

Carole Goble
University of Manchester 
UK