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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