r12 - 2013-09-20 - 23:09:32 - RahulKatareYou are here: NTP >  Dev Web > GoogleSummerOfCode > GSoC2013StartupAnalysisRahul
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Clock Startup Analysis - Rahul


Ntpd program is an operating system daemon which sets and maintains system time of the day in synchronism with internet standard time servers. It operates by exchanging one or more messages with one or more configured servers at designated poll intervals. Ntpd currently applies small corrections (-500, 0 or 500 ppm discrete corrections) to the system time every second. If ntpd uses adjtime(), it updates the system clock every second. But some clock implementations do not provide small update to system clock. So there is a clock model which provides a kernel discipline called ntp_adjtime() which is used by Ntpd to adjust several parameters of the clock. There are two aspects to time corrections, applying an offset and adjusting the clock-frequency. The idea here is to perform a startup analysis of the time offset and the frequency correction that needs to be applied. The objective is to, first collect the data from N servers, using that calculate the offset and frequency adjustment that needs to be done.

Related Items: RFC 1589, https://www.ntp.org/ntpfaq/NTP-s-algo-kernel.htm


  • Project Design
  • Framework
  • Collecting Data from Single Host(Already done in the current code) and Analyzing it.
  • Calculating slope and offset from the data and applying the correction to the clock and observing the effect.
  • Collecting Data from Multiple Hosts.
  • Exploring techniques to analyze data from multiple hosts.
  • Test on both wired and wireless connections.


Date Task Description % Done
05-27 Community Bonding Students get to know mentors, read documentation, get up to speed to begin working on their projects. choice-yes
06-17 Coding Begins Students begin coding for their GSoC projects choice-yes
07-01 Lookup of existing code Understanding the current code choice-yes
07-27 Will be Away Will be Travelling from home to my institute choice-yes
07-29 BO Midterm Evals Mentors and students can begin submitting mid-term evaluations. choice-yes
08-02 EO Midterm Evals Mid-term evaluations deadline. choice-yes
09-16 Wrap-up Suggested "Pencils Down" date. Take a week to scrub code, write tests, improve documentation, etc. choice-yes
09-23 Firm "Pencils Down" Mentors, students and organization administrators can begin submitting final evaluations to Google.  
09-27 Final Evaluation Final Evaluations Deadline  
09-27 Code Samples Students begin uploading code samples  
10-01 Final Results Final Results Announced  

Discussion and Comments

Rahul, on 7/26 will your travels only take 1 day?

-- HarlanStenn - 2013-06-18

Yes, I'll be travelling for a day.

-- RahulKatare - 2013-06-23

Change of plans, will be travelliing on 7/27 for a day.

-- RahulKatare - 2013-07-13

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