Messages in this thread | | | Date | Thu, 07 Oct 2004 14:13:45 -0600 | From | Chris Friesen <> | Subject | question on update_wall_time_one_tick() |
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If we call update_wall_time_one_tick(), with a mode of ADJ_OFFSET_SINGLESHOT, the offset can be up to +/-512000 usec.
However, in update_wall_time_one_tick(), the offset adjustment each tick is limited to the range of -tickadj < x < tickadj. On many current systems, tickadj is 1. Thus, a large adjustment takes a *long* time.
While we are doing this offset change, if someone else requests another offset, it will totally overwrite any unapplied portion of the offset from the previous call:
/* Changes by adjtime() do not take effect till next tick. */ if (time_next_adjust != 0) { time_adjust = time_next_adjust; time_next_adjust = 0; }
Thus, doing an offset of +512000, immediately followed by an offset of -512000, will leave you with a significant negative offset.
Is this the desired behaviour?
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