<html><head/><body><html><head><meta http-equiv="Content-Type" content="text/html; charset=us-ascii" /></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">This depends on how you're running ntpd. If you have "-x" on the command line, yes - ntpd will not step.<br>
<br>
If not, there are circumstances it will step - clock diffs in excess of 128ms iirc?<br>
<br>
Who knows what newer implementations like chrony or openntpd do!<br><br><div class="gmail_quote">Glyph <glyph@twistedmatrix.com> wrote:<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
<br /><div><div>On Oct 28, 2012, at 9:01 AM, Christopher Armstrong <<a href="mailto:radix@twistedmatrix.com">radix@twistedmatrix.com</a>> wrote:</div><br class="Apple-interchange-newline" /><blockquote type="cite"><div style="font-family: Menlo; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; ">I'm not speaking from experience, admittedly. How big exactly are the steps in NTP skewing?</div></blockquote><br /></div><div>There are two things NTP can do: stepping and slewing. (Skewing is not one of them.)</div><div><br /></div><div>If you're stepping, the steps can be arbitrarily large. This is what ntpdate does.</div><div><br /></div><div>If you're slewing, there are no steps. This is what ntpd does. The frequency of your clock is just adjusted up or down by a small (configurable) amount. Generally not enough to affect the pitch or network latency of 20ms sound sampling. In fact, it would generally help, not hurt, because the only reason ntp would be issuing a slew is that your clock is faster or slower than real time anyway.</div><div><br /></div><div>PEP 418 <<a href="http://www.python.org/dev/peps/pep-0418/">http://www.python.org/dev/peps/pep-0418/</a>> covers this stuff in a lot of detail; especially the glossary.</div><div><br /></div><div>-glyph</div><div><br /></div><p style="margin-top: 2.5em; margin-bottom: 1em; border-bottom: 1px solid #000"></p><pre style="white-space: pre-wrap; word-wrap:break-word; font-family: sans-serif; margin-top: 0px"><hr /><br />Twisted-Python mailing list<br />Twisted-Python@twistedmatrix.com<br /><a href="http://twistedmatrix.com/cgi-bin/mailman/listinfo/twisted-python">http://twistedmatrix.com/cgi-bin/mailman/listinfo/twisted-python</a><br /></pre></blockquote></div><br>
-- <br>
Sent from my mobile device, please excuse brevity and typos.</body></html></body></html>