Query cancelled errors

We have encountered numerous instances when we have encountered the following error message:
        ERROR:  Query was cancelled.
Specific instances include:

Attempting an export with pg_dump:
        % pg_dump -c -C -D -F t -f /data/export/daily/CT_ADMIN~EXPORT~20030916.sql.tar CT_ADMIN
        % pg_dump: query to obtain list of data types failed: ERROR:  Query was cancelled.

Doing a vacuum:
        % vacuumdb -a -f -z -v
        % INFO:  --Relation pg_catalog.pg_conversion--
        INFO:  Pages 2: Changed 0, reaped 0, Empty 0, New 0; Tup 114: Vac 0, Keep/VTL 0/0, UnUsed 0, MinLen 117, MaxLen 117; Re-using: Free/Avail. Space 2208/2096; EndEmpty/Avail. Pages 0/1.
        CPU 0.00s/0.00u sec elapsed 0.00 sec.
        INFO:  Index pg_conversion_default_index: Pages 2; Tuples 114.
        CPU 0.00s/0.01u sec elapsed 0.00 sec.
        INFO:  Index pg_conversion_name_nsp_index: Pages 4; Tuples 114.
        CPU 0.00s/0.00u sec elapsed 0.00 sec.
        INFO:  Index pg_conversion_oid_index: Pages 2; Tuples 114.
        CPU 0.00s/0.00u sec elapsed 0.00 sec.
        INFO:  Rel pg_conversion: Pages: 2 --> 2; Tuple(s) moved: 0.
        CPU 0.00s/0.00u sec elapsed 0.00 sec.
        INFO:  Analyzing pg_catalog.pg_conversion
        INFO:  --Relation pg_catalog.pg_depend--
        INFO:  Pages 21: Changed 0, reaped 1, Empty 0, New 0; Tup 2800: Vac 0, Keep/VTL 0/0, UnUsed 56, MinLen 49, MaxLen 49; Re-using: Free/Avail. Space 3388/3148; EndEmpty/Avail. Pages 0/1.
        CPU 0.01s/0.00u sec elapsed 0.01 sec.
        INFO:  Index pg_depend_depender_index: Pages 17; Tuples 2800: Deleted 0.
        CPU 0.01s/0.00u sec elapsed 0.08 sec.
        INFO:  Index pg_depend_reference_index: Pages 21; Tuples 2800: Deleted 0.
        CPU 0.01s/0.02u sec elapsed 0.06 sec.
        ERROR:  Query was cancelled.
        vacuumdb: vacuum  testdb failed

Getting table comments inside psql session:
        CT_ADMIN=# \dd pg_conversion
        ERROR:  Query was cancelled.

Any ideas?

--

David Rickard
Software Engineer
The GTS Companies
A TechBooks Company

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