In response to Tom Lane <tgl at sss.pgh.pa.us>:

> Bill Moran <wmoran at collaborativefusion.com> writes:
> > (Very) Occasionally, we see these errors from Slony:
> > ERROR  remoteListenThread_1: "listen "_schema_name"; " - ERROR:  could not read block 2 of relation
> 
> > To the tune of, seen it about 5 times in the last 6 months.  Now that we
> > have a few examples of it, it seems to occur only when the server is
> > under heavy load.
> 
> > Is there anything here to be concerned about?
> 
> Yeah, I'd say so.  But it's hard to guess what's happening since you
> left out the most important part of the message, ie the kernel error
> message.

Nothing in the kernel logs at the time this occurred.

The PostgreSQL log has one mysterious entry:
Aug 27 00:18:46 src at db03 postgres[37902]: [440-1] LOG:  duration: 3529.878 ms  statement: listen "_schema_name";

3 1/2 seconds seems like a long time for a listen command.  I wonder
if Slony just got tired of waiting?

> > This is PostgreSQL 8.3 on FreeBSD 6, using the latest Slony 1.2  (although
> > there have been varying versions over the last 6 months)
> 
> 8.3.what?

Currently 8.3.7, but as I mentioned, this has happened 5 times in the last
6 months, and versions have been ever climbing over that period (although
I believe this server's been on the 8.3 branch for that entire period)

[wmoran at db03 ~]$ pkg_info | grep postgres
postgresql-client-8.3.7 PostgreSQL database (client)
postgresql-contrib-8.3.7_1 The contrib utilities from the PostgreSQL distribution
postgresql-server-8.3.7 The most advanced open-source database available anywhere


-- 
Bill Moran
Collaborative Fusion Inc.
http://people.collaborativefusion.com/~wmoran/

wmoran at collaborativefusion.com
Phone: 412-422-3463x4023

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