Remove inaccurate references to corruption, remove SEGTERM suggestion…

…, update information links to current docs. Postgres is carefully designed such that data is not corrupted on crashes or unclean shutdowns - the main tradeoff is that WAL replay is needed on startup. In practice, SIGTERM can cause unexpected long delays to shutdowns - often during maintenance windows - so best not to activaly suggest this. The links back to official Postgres documentation seem sufficient.

Dockerfile-alpine.template

@@ -232,18 +232,12 @@ ENTRYPOINT ["docker-entrypoint.sh"]
 # We set the default STOPSIGNAL to SIGINT, which corresponds to what PostgreSQL
 # calls "Fast Shutdown mode" wherein new connections are disallowed and any
 # in-progress transactions are aborted, allowing PostgreSQL to stop cleanly and
-# flush tables to disk, which is the best compromise available to avoid data
-# corruption.
+# flush tables to disk.
 #
-# Users who know their applications do not keep open long-lived idle connections
-# may way to use a value of SIGTERM instead, which corresponds to "Smart
-# Shutdown mode" in which any existing sessions are allowed to finish and the
-# server stops when all sessions are terminated.
-#
-# See https://www.postgresql.org/docs/12/server-shutdown.html for more details
+# See https://www.postgresql.org/docs/current/server-shutdown.html for more details
 # about available PostgreSQL server shutdown signals.
 #
-# See also https://www.postgresql.org/docs/12/server-start.html for further
+# See also https://www.postgresql.org/docs/current/server-start.html for further
 # justification of this as the default value, namely that the example (and
 # shipped) systemd service files use the "Fast Shutdown mode" for service
 # termination.
@@ -253,10 +247,10 @@ STOPSIGNAL SIGINT
 # An additional setting that is recommended for all users regardless of this
 # value is the runtime "--stop-timeout" (or your orchestrator/runtime's
 # equivalent) for controlling how long to wait between sending the defined
-# STOPSIGNAL and sending SIGKILL (which is likely to cause data corruption).
+# STOPSIGNAL and sending SIGKILL.
 #
 # The default in most runtimes (such as Docker) is 10 seconds, and the
-# documentation at https://www.postgresql.org/docs/12/server-start.html notes
+# documentation at https://www.postgresql.org/docs/current/server-start.html notes
 # that even 90 seconds may not be long enough in many instances.
 
 EXPOSE 5432

Dockerfile-debian.template

@@ -192,18 +192,12 @@ ENTRYPOINT ["docker-entrypoint.sh"]
 # We set the default STOPSIGNAL to SIGINT, which corresponds to what PostgreSQL
 # calls "Fast Shutdown mode" wherein new connections are disallowed and any
 # in-progress transactions are aborted, allowing PostgreSQL to stop cleanly and
-# flush tables to disk, which is the best compromise available to avoid data
-# corruption.
+# flush tables to disk.
 #
-# Users who know their applications do not keep open long-lived idle connections
-# may way to use a value of SIGTERM instead, which corresponds to "Smart
-# Shutdown mode" in which any existing sessions are allowed to finish and the
-# server stops when all sessions are terminated.
-#
-# See https://www.postgresql.org/docs/12/server-shutdown.html for more details
+# See https://www.postgresql.org/docs/current/server-shutdown.html for more details
 # about available PostgreSQL server shutdown signals.
 #
-# See also https://www.postgresql.org/docs/12/server-start.html for further
+# See also https://www.postgresql.org/docs/current/server-start.html for further
 # justification of this as the default value, namely that the example (and
 # shipped) systemd service files use the "Fast Shutdown mode" for service
 # termination.
@@ -213,10 +207,10 @@ STOPSIGNAL SIGINT
 # An additional setting that is recommended for all users regardless of this
 # value is the runtime "--stop-timeout" (or your orchestrator/runtime's
 # equivalent) for controlling how long to wait between sending the defined
-# STOPSIGNAL and sending SIGKILL (which is likely to cause data corruption).
+# STOPSIGNAL and sending SIGKILL.
 #
 # The default in most runtimes (such as Docker) is 10 seconds, and the
-# documentation at https://www.postgresql.org/docs/12/server-start.html notes
+# documentation at https://www.postgresql.org/docs/current/server-start.html notes
 # that even 90 seconds may not be long enough in many instances.
 
 EXPOSE 5432