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Subjectquestion on update_wall_time_one_tick()

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?

Chris
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