bug#23064: herd has incomplete status reporting, not so helpful

[Ludovic Courtès]

Danny Milosavljevic <address@hidden> skribis:

>> Could you try this and report back?
>
> $ patch -p1 < ...
> $ sudo ./pre-inst-env guix system reconfigure /etc/config.scm
> $ sudo herd stop postgres
> $ sudo herd start postgres
> Service postgres has been started.
> $ tail -f /var/log/messages 
> Mar 22 20:15:51 localhost nscd: 213 monitored file `/etc/services` was 
> created, adding watch
> Mar 22 20:15:51 localhost nscd: 213 monitored file `/etc/services` was 
> written to
> Mar 22 20:20:40 localhost postgres[2115]: [1-1] FATAL:  database files are 
> incompatible with server
> Mar 22 20:20:40 localhost postgres[2115]: [1-2] DETAIL:  The data directory 
> was initialized by PostgreSQL version 9.3, which is not compatible with this 
> version 9.5.1.

Great, thanks for testing!  Pushed as
9b1cee97a5a75766cb52553111794c758c4f1651.

> Although it would be nice to have shepherd have a field in "herd status" 
> which tells you when it respawned the service in < 1 s intervals (or maybe if 
> it respawned it < 1 s after the initial start) - or maybe just how long ago 
> it was (last) started and when the actual herd start command was :-)

In trying to implement that, I realized there’s a bug in respawn delay
handling.  More on that later.

Ludo’.