Justin Pasher wrote: > Hello, > > I have a server running PostgreSQL 8.1.15-0etch1 (Debian etch) that was > recently put into production. Last week a developer started having a problem > with his psql connection being terminated every couple of minutes when he > was running a query. When I look through the logs, I noticed this message. > > 2009-01-09 08:09:46 CST LOG: autovacuum process (PID 15012) was terminated > by signal 11 Segmentation fault - probably a bug or bad RAM. > I looked through the logs some more and I noticed that this was occurring > every minute or so. The database is a pretty heavily utilized system > (judging by the age(datfrozenxid) from pg_database, the system had run > approximately 500 million queries in less than a week). I noticed that right > before every autovacuum termination, it tried to autovacuum a database. > > 2009-01-09 08:09:46 CST LOG: transaction ID wrap limit is 4563352, limited > by database "database_name" > > It was always showing the same database, so I decided to manually vacuum the > database. Once that was done (it was successful the first time without > errors), the problem seemed to go away. I went ahead and manually vacuumed > the remaining databases just to take care of the potential xid wraparound > issue. I'd be suspicious of possible corruption in autovacuum's internal data. Can you trace these problems back to a power-outage or system crash? It doesn't look like "database_name" itself since you vacuumed that successfully. If autovacuum is running normally now, that might indicate it was something in the way autovacuum was keeping track of "database_name". It's also probably worth running some memory tests on the server - (memtest86 or similar) to see if that shows anything. Was it *always* the autovacuum process getting sig11? If not then it might just be a pattern of usage that makes it more likely to use some bad RAM. -- Richard Huxton Archonet Ltd -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
