[Pkg-postgresql-public] Bug#759725: postgresql-common: non-synchronous service postgresql start/stop/reload

[beuc]

Package: postgresql-common
Version: 160
Severity: important

Hi,

When working on the FusionForge installation system today I noticed
that in Debian Jessie, running:

  service postgresql start

(or stop, or reload), is now asynchronous, due to using the new
PostgreSQL systemd init scripts.

Previously I could rely on the init script to come back when the
database was properly stopped and flushed.  Right now the command
returns immediately and starts/stops/reloads in the background.

My scripts need to modify the PostgreSQL listen address and reload it
before populating the database through the PHP application.  They also
need to stop/backup/start the server for quick load/restore during our
testsuite.  Due to this change the installation system fails randomly
due to race condition.

I found it basically impossible to work-around this issue in a
portable manner:

- 'service postgresql status' is not reliable: it usually says the
  service is stopped far before the shutdown is complete. I also got a
  few cases where it reported active service with no running daemon.

- the 'postgresql' process may be stopped already, but pg_ctl still
  doing a faststop (especially when there's data to flush to disk) -
  there may also be other PostgreSQL processes I don't know about;
  so 'ps' is not reliable either.

- the postgresql control commands vary between Debian and RedHat
  (pg_ctl vs. pg_clusterctl), and they need a data directory that can
  be in varied, possibly multiple, locations. Using 'pg_*ctl' manually
  is error-prone and long.

- in any case that will require fare more code and testing than
  'service postgresql xxx'

Please consider maintaining 'service postgresql start/stop/reload'
synchronous even with systemd.

Cheers!
Sylvain


-- System Information:
Debian Release: jessie/sid
  APT prefers testing-updates
  APT policy: (500, 'testing-updates'), (500, 'testing')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 3.14-2-amd64 (SMP w/8 CPU cores)
Locale: LANG=eo.UTF-8, LC_CTYPE=eo.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages postgresql-common depends on:
ii  adduser                   3.113+nmu3
ii  debconf [debconf-2.0]     1.5.53
ii  init-system-helpers       1.21
ii  lsb-base                  4.1+Debian13
ii  postgresql-client-common  160
ii  procps                    1:3.3.9-7
ii  ssl-cert                  1.0.34
ii  ucf                       3.0030

Versions of packages postgresql-common recommends:
ii  logrotate  3.8.7-1

postgresql-common suggests no packages.

-- debconf information excluded