Description of problem: Many of our customers have expressed a desire to synchronise multiple systems in a datacenter to sub-millisecond time resolutions. Currently, NTP is unable to maintain this level of synchronization. We should investigate the utility of combining a GPS precision time source with either a multi-drop serial interface or a dedicated ethernet interface, as a periodic update to NTP.
Ah re-reading my above, I realized that I didn't state that I'm aware that the current PPS patch is unsuitable for inclusion. We should look at starting from that and possibly morphing it into a general purpose solution that: 1. Doesn't add it's own system calls 2. Possibly provides a clocksource 3. Doesn't suck
Some links for consideration LinuxPPS website: http://wiki.enneenne.com/index.php/LinuxPPS_support Seventh repost of PPS patch series to LKML: http://linux.derkeiler.com/Mailing-Lists/Kernel/2008-09/msg04640.html
Would this just be for RHEL, or would Fedora benefit as well? I would like to have this functionality without breaking kernel updates.
At present we're just talking about it for the MRT RT (realtime) kernel. I don't know of any plans to add it to RHEL or Fedora, since it's not upstream yet.
Clark, is this still something we want to pursue?
PPS has been added to the 2.6.31 upstream kernel. closing