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timedated: update spike handling

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This commit is contained in:
Kay Sievers 2014-03-16 23:51:50 +01:00
parent 3dbc762003
commit a47b9e6283
1 changed files with 13 additions and 13 deletions
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26
src/timedate/timedate-sntp.c
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@ -404,18 +404,6 @@ static bool sntp_sample_spike_detection(SNTPContext *sntp, double offset, double
sntp->packet_count++;
jitter = sntp->samples_jitter;
/* ignore samples when resyncing */
if (sntp->poll_resync)
return false;
/* we need a few samples before we calculate anything */
if (sntp->packet_count < 3)
return false;
/* always accept sample if we are farther off than the round trip delay */
if (fabs(offset) > delay)
return false;
/* calculate new jitter value from the RMS differences relative to the lowest delay sample */
for (idx_min = idx_cur, i = 0; i < ELEMENTSOF(sntp->samples); i++)
if (sntp->samples[i].delay > 0 && sntp->samples[i].delay < sntp->samples[idx_min].delay)
@ -426,8 +414,20 @@ static bool sntp_sample_spike_detection(SNTPContext *sntp, double offset, double
j += square(sntp->samples[i].offset - sntp->samples[idx_min].offset);
sntp->samples_jitter = sqrt(j / (ELEMENTSOF(sntp->samples) - 1));
/* ignore samples when resyncing */
if (sntp->poll_resync)
return false;
/* always accept offset if we are farther off than the round-trip delay */
if (fabs(offset) > delay)
return false;
/* we need a few samples before looking at them */
if (sntp->packet_count < 4)
return false;
/* do not accept anything worse than the maximum possible error of the best sample */
if (abs(offset) > sntp->samples[idx_min].delay)
if (fabs(offset) > sntp->samples[idx_min].delay)
return true;
/* compare the difference between the current offset to the previous offset and jitter */