I can't cancel/terminate query.

Hi! i have many too long time queries, the oldest is almost 16 days,
so i tried to cancel and terminate with pg_cancel_backend and
pg_terminate_backend but queries is still running.

STIME ELAPSED ELAPSED %CPU PID COMMAND
jun27 15-23:05:46 1379146 0.3 29660 postgres: argos_admin bdkairos
127.0.0.1(55605) SELECT
jun27 15-23:05:46 1379146 0.3 29659 postgres: argos_admin bdkairos
127.0.0.1(55604) SELECT
jun27 15-23:05:46 1379146 0.3 29658 postgres: argos_admin bdkairos
127.0.0.1(55603) SELECT
jun27 15-23:05:16 1379116 0.3 29909 postgres: argos_admin bdkairos
127.0.0.1(55767) SELECT
jun27 15-23:04:51 1379091 0.3 30097 postgres: argos_admin bdkairos
127.0.0.1(55909) SELECT
jun27 15-23:03:49 1379029 0.3 30661 postgres: argos_admin bdkairos
127.0.0.1(56303) SELECT
...
What should i do to safely close that queries, before to use kill command
in linux?

I have Postgres 9.4 running on debian jessie.

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