Lines Matching +full:system +full:- +full:clock +full:- +full:frequency
10 <!-- #BeginDate format:En2m -->27-Jan-2014 05:31<!-- #EndDate -->
13 <! -- This is deliberately not a mailto -- > <jhawk@MIT.EDU>
23 <A HREF="solaris-dosynctodr.html">Here is the report</A>.
26 variable <I>dosynctodr</I> to zero (meaning "do not synchronize the clock
27 to the hardware time-of-day clock"). This can be done with the
30 tickadj -s
34 echo dosynctodr/W0 | adb -k -w /dev/ksyms /dev/mem
37 Or, it can also be set by adding a line to /etc/system:
43 systems use to control microseconds added to the system time every
44 clock tick (c.f. <A HREF="#frequency_tolerance">Dealing
45 with Frequency Tolerance Violations</A>), Solaris has the variables
49 nanoseconds and microseconds, respectively, added to the system clock
50 each clock interrupt. Enterprising souls may set these based on
60 operating system releases. There is enough variation in the core operating
61 system support for timekeeping that a rebuild of ntpd for the idiosyncracies
62 of your specific operating system version is advisable.
70 <h4>Dealing with Frequency Tolerance Violations (<tt>tickadj</tt> and
72 The NTP Version 3 specification RFC-1305 calls for a maximum
73 oscillator frequency tolerance of +-100 parts-per-million (PPM), which is
76 tolerance, NTP will automatically compensate for the frequency errors of the
79 release, this tolerance has been increased to +-500 PPM. <p>However, in the
83 <tt>tick</tt> is the increment in microseconds added to the system time on
84 each interval- timer interrupt, while the variable <tt>tickadj</tt> is used
86 the time is being adjusted via a call to the system routine
104 inspection or modification of kernel variables other than at system build
110 small adjustments to the clock, usually at one-second intervals. If
122 cause the clock to run with a very large frequency error, as with SunOS
125 synchronize the system clock to the time-of-day clock, something you really
135 intervals, <tt>ntpd</tt> will complain if the frequency error is greater
136 than 500 PPM. For machines with a value of <tt>tick</tt> in the 10-ms range,
137 a change of one in the value of <tt>tick</tt> will change the frequency by
141 source (eyeball-and-wristwatch will do) over a day or more. Multiply the
146 <tt>tickadj</tt> -t 9999 -a 5 -s
149 off the clock/calendar chip fiddle. This line can be added to the <tt
153 that kept reasonable time and would make their <tt>adjtime()</tt> system
171 4023118</A>. Bryan Cantrill <! -- <bmc@eng.sun.com> --> of Sun
183 Solaris 2.2 and later contain completely re-written clock code to
185 re-written clock code is that adjtime does not round off its
194 Solaris 2.1 contains fairly traditional clock code, with <I>tick</I>
201 tickadj -s -a 1000
202 <BR>ntpdate -v server1 server2
204 <BR>ntpdate -v server1 server2
206 <BR>tickadj -a 200
210 The first tickadj turns of the time of day clock and sets the tick
220 clock should be within 2 seconds of the correct time.
222 The second tickadj set the tick adjust system value to 5 microseconds.