From mboxrd@z Thu Jan  1 00:00:00 1970
From: Richard Cochran <richardcochran@gmail.com>
Date: Tue, 20 Oct 2015 10:54:08 +0200
Subject: [Intel-wired-lan] [PATCH v4 1/4] Produce system time from
	correlated clocksource
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 <alpine.DEB.2.11.1510132116480.25029@nanos>
 <op.x6iyd7gq1774gr@chall-mobl2.amr.corp.intel.com>
 <alpine.DEB.2.11.1510151014330.3960@nanos>
 <op.x6r25dza1774gr@chall-mobl2.amr.corp.intel.com>
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On Mon, Oct 19, 2015 at 05:36:56PM -0700, John Stultz wrote:
> If we're only tracking 4ms of history, how does this solution
> measurably improve the error over using the timestamps to generate
> MONOTONIC_RAW clock deltas (which doesn't require keeping any history)
> and using getnstime_raw_and_real to take an anchor point to calculate
> the delta from?  Why is adding complexity necessary?

This idea is variant of what I suggested in another reply in this
thread.  To my understanding, there is no need at all to keep a
history arbitrarily 4 ms long.  Instead, the DSP driver (or whoever
else may need such a thing) can simply sample the system time at the
rate needed for that particular application.

Thanks,
Richard