[pgpool-committers: 8327] pgpool: Change the default value for log_line_prefix.

[Tatsuo Ishii]

Change the default value for log_line_prefix.

Currently the default value for log_line_prefix is "%t pid: %p", which
is the long standing default. Also since 4.2, %a (application name) and
since 4.3 %m (timestamp with millisecond) are available.

This commit changes %t" (timestamp without millisecond) to %m because
PostgreSQL's default is already %m.  Also add %a so that admins easily
distinguish particular process's log.

In summary the default is changed from:
"%t pid: %p"
to:
"%m %a pid: %p"

This change will be applied to not only master branch but 4.3
stable. There's not so many 4.3 users yet and changing the default
will not affect existing 4.3 users. Only new 4.3 will enjoy the new
default.

Discussion: https://www.pgpool.net/pipermail/pgpool-hackers/2022-January/004098.html

Branch
------
master

Details
-------
https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=228da1fc32a2335cb19fb3abd72b4c4c1056141a

Modified Files
--------------
doc.ja/src/sgml/connection-pooling.sgml | 7 ++-----
doc/src/sgml/connection-pooling.sgml    | 4 +---
src/config/pool_config_variables.c      | 2 +-
src/sample/pgpool.conf.sample-stream    | 2 +-
4 files changed, 5 insertions(+), 10 deletions(-)