From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <1d8097739572ba276fa5000f1a77ebc0@plan9.bell-labs.com> From: David Presotto To: 9fans@cse.psu.edu Subject: Re: [9fans] timesync is slow to set the time after boot In-Reply-To: <3E7432B3.2050805@powell.name> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Date: Sun, 16 Mar 2003 08:28:19 -0500 Topicbox-Message-UUID: 81030746-eacb-11e9-9e20-41e7f4b1d025 No, it was just trying to get any system startup effects out of the measurement. It just mattered for ntp round trip, not for the real time clock. For NTP there's an assumption that the round trip time twixt the systems is equally separated in the two directions. When the system is coming up, especially on diskless systems, the ether can stay pretty busy for seconds after the boot as different things page in, db's get read, etc. Dropping the first sample was just an attempt to avoid that since most of our systems (except our web server) have settled after a minute. However, I booted our systems here a few dozen times since then and looked at the time convergence. It doesn't seem to make a difference either way so the check stays out.