[GENERAL] pqReadData() -- backend closed the channel unexpectedly (huh?)

[Frank Miles]

Hello all:

        I have a simple database which is now exhibiting some strange symptoms.
The most obviously sick is where I try to delete a record in a table, and
get the response:

        pqReadData() -- backend closed the channel unexpectedly.
                This probably means the backend terminated abnormally
                before or while processing the request.
        The connection to the server was lost. Attempting reset: Failed.

I dropped the database, and restored it from a backup.  Same results.
Vacuum analyze doesn't complain.  I turned on debug messages from the
postmaster, but didn't see anything that pointed to the problem.  For the
record, the log shows:

        StartTransactionCommand
        query: SELECT usesuper FROM pg_user WHERE usename = 'fpm'
        ProcessQuery
        CommitTransactionCommand
        StartTransactionCommand
        query:  select * from units ;
        ProcessQuery
        CommitTransactionCommand
        StartTransactionCommand
        query: delete from units where unit_id = 5;
        ProcessQuery
        /opt/pgsql/bin/postmaster: reaping dead processes...
        /opt/pgsql/bin/postmaster: CleanupProc: pid 21004 exited with status 139
        Server process (pid 21004) exited with status 139 at Tue Nov  7 11:04:56 2000
        Terminating any active server processes...
        Server processes were terminated at Tue Nov  7 11:04:56 2000
        Reinitializing shared memory and semaphores
        shmem_exit(0)
        binding ShmemCreate(key=52e325, size=1104896)
        /opt/pgsql/bin/postmaster: ServerLoop:          handling reading 5
        /opt/pgsql/bin/postmaster: ServerLoop:          handling reading 5
        DEBUG:  Data Base System is starting up at Tue Nov  7 11:04:56 2000
        DEBUG:  Data Base System was interrupted being in production at Tue Nov  7 
11:04:40 2000
        /opt/pgsql/bin/postmaster: ServerLoop:          handling writing 5
        The Data Base System is starting up
        /opt/pgsql/bin/postmaster: ServerLoop:          handling writing 5
        DEBUG:  Data Base System is in production state at Tue Nov  7 11:04:56 2000
        proc_exit(0)
        shmem_exit(0)
        exit(0)
        /opt/pgsql/bin/postmaster: reaping dead processes...

Version: 7.0.2.

Any suggestions on how/where to look for the source of the problem?

Thanks....

        -frank