Cron'd dumpall failing?

I truly hoping I'm missing something silly here. I've got a cron job to
run a dumpall each early am. It fails, and I get a handful of emails.
The first reads like this:

pg_dump: [archiver (db)] connection to database "adocs" failed: FATAL: sorry, too many clients already
pg_dumpall: pg_dump failed on database "adocs", exiting

...and then as we go along we get this one repeating for each database:

pg_dump: WARNING: out of shared memory
pg_dump: SQL command failed
pg_dump: Error message from server: ERROR: out of shared memory
HINT: You may need to increase max_locks_per_transaction.
pg_dump: The command was: SELECT sequence_name, last_value, increment_by, CASE WHEN increment_by > 0 AND max_value = 9223372036854775807 THEN NULL WHEN increment_by < 0 AND max_value = -1 THEN NULL ELSE max_value END AS max_value, CASE WHEN increment_by > 0 AND min_value = 1 THEN NULL WHEN increment_by < 0 AND min_value = -9223372036854775807 THEN NULL ELSE min_value END AS min_value, cache_value, is_cycled, is_called from tabproj_skey
pg_dumpall: pg_dump failed on database "XXXXX", exiting

The cron entry (for user root) is

* 1 * * * /root/dumpall.sh > /dev/null

and the routine in question is this:

pg_dumpall -U postgres > /home/bups/bsource/pg/dhost2.dumpall
chown bups:root /home/bups/bsource/pg/dhost2.dumpall
chmod 600 /home/bups/bsource/pg/dhost2.dumpall