On Thu, Jul 21, 2022 at 02:13:29PM +0200, Jakub Raczyński wrote: > My interpretation is based only on ntpshmmon tool - it clearly shows that > ntpshm servo is only fed when PTP portState is set to Slave. So it is used > only to write to the segment, but phc2sys clearly controls when it is done. > Since ntpd does not communicate with phc2sys then whether it works or not is > only based on phc2sys.
You said something about ntpd reset. I'm not sure what that is. If there was something removing the segment (e.g. a script using ipcrm) before phc2sys reverses the direction, it would create a new SHM, which wouldn't be monitored by ntpshmmon started earlier. > It seems you have great feature of phc2sys that allows to synchronize ntpshm > servo in Slave state and use CLOCK_REALTIME as Master, yet you say like it > does not exist. And again, I intend to use it that way. I am not trying to > read anything from ntpshm. ntpshm doesn't synchronize anything. It just provides data for another process to synchronize the clock. ntpd can synchronize CLOCK_REALTIME, but not a PHC, and even if it could, it wouldn't know when it should switch. You need two phc2sys instances. -- Miroslav Lichvar _______________________________________________ Linuxptp-users mailing list Linuxptp-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linuxptp-users
