As widely reported on the internet, some Linux systems after the leapsecond was inserted are experiencing futex related load spikes (usually connected to MySQL, Firefox, Thunderbird, Java, etc).
An apparent for this issue workaround is running: $ date -s "`date`" Credit: http://www.sheeri.com/content/mysql-and-leap-second-high-cpu-and-fix I this issue is due to the leapsecond being added without calling clock_was_set() to notify the hrtimer subsystem of the change. The workaround functions as it forces a clock_was_set() call from settimeofday(). This fix adds the required clock_was_set() calls to where we adjust for leapseconds. NOTE: This fix *depends* on the previous fix, which allows clock_was_set to be called from atomic context. Do not try to apply just this patch. CC: Prarit Bhargava <[email protected]> CC: [email protected] CC: Thomas Gleixner <[email protected]> CC: [email protected] Reported-by: Jan Engelhardt <[email protected]> Signed-off-by: John Stultz <[email protected]> --- kernel/time/timekeeping.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 6f46a00..cc2991d 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -963,6 +963,8 @@ static cycle_t logarithmic_accumulation(cycle_t offset, int shift) leap = second_overflow(timekeeper.xtime.tv_sec); timekeeper.xtime.tv_sec += leap; timekeeper.wall_to_monotonic.tv_sec -= leap; + if (leap) + clock_was_set(); } /* Accumulate raw time */ @@ -1079,6 +1081,8 @@ static void update_wall_time(void) leap = second_overflow(timekeeper.xtime.tv_sec); timekeeper.xtime.tv_sec += leap; timekeeper.wall_to_monotonic.tv_sec -= leap; + if (leap) + clock_was_set(); } timekeeping_update(false); -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
