[ClusterLabs] Antw: [EXT] Coming in Pacemaker 2.0.4: dependency on monotonic clock for systemd resources

[Ken Gaillot]

On Wed, 2020-03-11 at 08:20 +0100, Ulrich Windl wrote:
> > > > Ken Gaillot <kgaillot at redhat.com> schrieb am 10.03.2020 um
> > > > 18:49 in
> 
> Nachricht
> <3098_1583862581_5E67D335_3098_1270_1_91b728456223eea7c8a00516a91ede1
> 8ab094530.c
> mel at redhat.com>:
> > Hi all,
> > 
> > This is not a big deal but I wanted to give a heads‑up for anyone
> > who
> > builds their own pacemaker packages.
> > 
> > With Pacemaker 2.0.4 (first release candidate expected next month),
> > we
> > are finally replacing our calls to the long‑deprecated ftime()
> > system
> > call with the "modern" clock_gettime().
> > 
> > As part of this, building pacemaker with support for systemd‑class
> > resources will now require that the underlying platform supports
> > clock_gettime() with CLOCK_MONOTONIC. Every platform we're aware of
> > that is used for pacemaker does, so this should not be an issue.
> > The
> > configure script will automatically determine whether support is
> > available.
> 
> You only have to take care not to compare CLOCK_MONOTONIC timestamps
> between
> nodes or node restarts. 

Definitely :)

They are used only to calculate action queue and run durations. For
most resource types those are optional (for reporting only), but
systemd resources require them (multiple status checks are usually
necessary to verify a start or stop worked, and we need to check the
remaining timeout each time).
-- 
Ken Gaillot <kgaillot at redhat.com>