[ClusterLabs] Possible idea for 2.0.0: renaming the Pacemaker daemons

[Ken Gaillot]

Hi all,

Andrew Beekhof brought up a potential change to help with reading
Pacemaker logs.

Currently, pacemaker daemon names are not intuitive, making it
difficult to search the system log or understand what each one does.

The idea is to rename the daemons, with a common prefix, and a name
that better reflects the purpose.

I think it's a great idea, but we have to consider two drawbacks:

* I'm about to release 2.0.0-rc2, and it's late in the cycle for a
major change. But if we don't do it now, it'll probably sit on the back
burner for a few years, as it wouldn't make sense to introduce such a
change shortly after a major bump.

* We can change *only* the names used in the logs, which will be
simple, but give us inconsistencies with what shows up in "ps", etc. Or
we can try to change everything -- process names, library names, API
function/structure names -- but that will impact other projects such as
sbd, crmsh, etc., potentially causing compatibility headaches.

What are your thoughts? Change or not? Now or later? Log tags, or
everything?

And the fun part, what would we change them to ...

Beekhof suggested renaming "pengine" to "cluster-planner", as an
example.

I think a prefix indicating pacemaker specifically would be better than
"cluster-" for grepping and intuitiveness.

For intuitiveness, long names are better ("pacemaker-FUNCTION"). On the
other hand, there's an argument for keeping names to 15 characters,
which is the default "ps" column width, and a reasonable limit for log
line tags. Maybe "pm-" or "pcmk-"? This prefix could also be used for
library names.

Looking at other projects with server processes, most use the
traditional "d" ending (for example, "rsyslogd"). A few add "-daemon"
("rtkit-daemon"), and others don't bother with any suffix ("gdm").

Here are the current names, with some example replacements:

 pacemakerd: PREFIX-launchd, PREFIX-launcher

 attrd: PREFIX-attrd, PREFIX-attributes

 cib: PREFIX-configd, PREFIX-state

 crmd: PREFIX-controld, PREFIX-clusterd, PREFIX-controller

 lrmd: PREFIX-locald, PREFIX-resourced, PREFIX-runner

 pengine: PREFIX-policyd, PREFIX-scheduler

 stonithd: PREFIX-fenced, PREFIX-stonithd, PREFIX-executioner

 pacemaker_remoted: PREFIX-remoted, PREFIX-remote

-- 
Ken Gaillot <kgaillot at redhat.com>