On Wed, Jan 18, 2017 at 11:17:23PM +0000, Collins, Cris L. wrote: > Can someone tell me why blacklisting a video driver, in this case nouveau, > in CentOS 7.2 would cause the following:
A driver that isn't loader cannot possibly affect your system. What you really mean is that the propriety nvidea driver causes this warning to appear, right? > Jan 18 17:52:20 ho3 ptp4l: [215.091] clockcheck: clock jumped forward or > running faster than expected! The clock check compares packet time stamps with the local CLOCK_MONOTONIC. Perhaps the nvidea driver spoils the check by causing really large latencies between packet arrival and the call to clock_gettime(CLOCK_MONOTONIC). You can instrument the code to confirm or deny this theory. > Time stamping parameters for ens6: > Capabilities: > hardware-transmit (SOF_TIMESTAMPING_TX_HARDWARE) > software-transmit (SOF_TIMESTAMPING_TX_SOFTWARE) > hardware-receive (SOF_TIMESTAMPING_RX_HARDWARE) > software-receive (SOF_TIMESTAMPING_RX_SOFTWARE) > software-system-clock (SOF_TIMESTAMPING_SOFTWARE) > hardware-raw-clock (SOF_TIMESTAMPING_RAW_HARDWARE) > PTP Hardware Clock: 2 Since you are using HW time stamping with a PHC, the extra latency will not affect the synchronization very much, and so you can disable the warning by setting sanity_freq_limit to zero. You could also try running ptp4l with a real time scheduling priority, using the chrt utility. Thanks, Richard ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ Linuxptp-users mailing list Linuxptp-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linuxptp-users
