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diff --git a/contrib/ntp/html/tickadj.htm b/contrib/ntp/html/tickadj.htm index 7dc11c0..3d9745e 100644 --- a/contrib/ntp/html/tickadj.htm +++ b/contrib/ntp/html/tickadj.htm @@ -1,107 +1,105 @@ -<HTML> -<HEAD> - <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> - <META NAME="GENERATOR" CONTENT="Mozilla/4.01 [en] (Win95; I) [Netscape]"> - <TITLE>tickadj - set time-related kernel variables -</TITLE> -</HEAD> -<BODY> - -<H3> -<TT>tickadj</TT> - set time-related kernel variables</H3> - -<HR> -<H4> -Synopsis</H4> -<TT>tickadj [ -Aqs ] [ -a <I>tickadj</I> ] [ -t <I>tick</I> ]</TT> -<H4> -Description</H4> -The <TT>tickadj</TT> program reads, and optionally modifies, several timekeeping-related -variables in the running kernel, via <TT>/dev/kmem</TT>. The particular -variables it is concerned with are <TT>tick</TT>, which is the number of -microseconds added to the system time during a clock interrupt, <TT>tickadj</TT>, -which sets the slew rate and resolution used by the <TT>adjtime</TT> system -call, and <TT>dosynctodr</TT>, which indicates to the kernels on some machines -whether they should internally adjust the system clock to keep it in line -with time-of-day clock or not. - -<P>We have a report that says starting with Solaris 2.6 we should -leave <I>dosynctodr</I> alone. -<A HREF="solaris-dosynctodr.html">Here is the report</A>. - -<P>By default, with no arguments, <TT>tickadj</TT> reads the variables -of interest in the kernel and displays them. At the same time, it determines -an "optimal" value for the value of the <TT>tickadj</TT> variable if the -intent is to run the <TT>ntpd</TT> Network Time Protocol (NTP) daemon, -and prints this as well. Since the operation of <TT>tickadj</TT> when reading -the kernel mimics the operation of similar parts of the <TT>ntpd</TT> program -fairly closely, this can be useful when debugging problems with <TT>ntpd</TT>. - -<P>Note that <TT>tickadj</TT> should be run with some caution when being -used for the first time on different types of machines. The operations -which <TT>tickadj</TT> tries to perform are not guaranteed to work on all -Unix machines and may in rare cases cause the kernel to crash. -<H4> -Command Line Options</H4> - -<DL> -<DT> -<TT>-a <I>tickadj</I></TT></DT> - -<DD> -Set the kernel variable <TT>tickadj</TT> to the value <I><TT>tickadj</TT></I> -specified.</DD> - -<DT> -<TT>-A</TT></DT> - -<DD> -Set the kernel variable <TT>tickadj</TT> to an internally computed "optimal" -value.</DD> - -<DT> -<TT>-t <I>tick</I></TT></DT> - -<DD> -Set the kernel variable <TT>tick</TT> to the value <I><TT>tick</TT></I> -specified.</DD> - -<DT> -<TT>-s</TT></DT> - -<DD> -Set the kernel variable <TT>dosynctodr</TT> to zero, which disables the -hardware time-of-year clock, a prerequisite for running the <TT>ntpd</TT> -daemon under SunOS4.</DD> - -<DT> -<TT>-q</TT></DT> - -<DD> -Normally, <TT>tickadj</TT> is quite verbose about what it is doing. The -<TT>-q</TT> flag tells it to shut up about everything except errors.</DD> -</DL> - -<H4> -Files</H4> - -<PRE> +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"> +<html> +<head> +<meta name="generator" content="HTML Tidy, see www.w3.org"> +<title>tickadj - set time-related kernel variables</title> +</head> +<body> +<h3><tt>tickadj</tt> - set time-related kernel variables</h3> + +<hr> +<h4>Synopsis</h4> + +<tt>tickadj [ -Aqs ] [ -a <i>tickadj</i> ] [ -t <i>tick</i> ]</tt> + +<h4>Description</h4> + +The <tt>tickadj</tt> program reads, and optionally modifies, +several timekeeping-related variables in the running kernel in some +machines, via <tt>/dev/kmem</tt>. The particular variables it is +concerned with are <tt>tick</tt>, which is the number of +microseconds added to the system time during a clock interrupt, +<tt>tickadj</tt>, which sets the slew rate and resolution used by +the <tt>adjtime</tt> system call, and <tt>dosynctodr</tt>, which +indicates to the kernels on some machines whether they should +internally adjust the system clock to keep it in line with +time-of-day clock or not. + +<p>Note that this program does NOT work in some kernels, in +particular Solaris 2.6 or later. See the <a href= +"solaris-dosynctodr.html">report</a>.</p> + +<p>By default, with no arguments, <tt>tickadj</tt> reads the +variables of interest in the kernel and displays them. At the same +time, it determines an "optimal" value for the value of the <tt> +tickadj</tt> variable if the intent is to run the <tt>ntpd</tt> +Network Time Protocol (NTP) daemon, and prints this as well. Since +the operation of <tt>tickadj</tt> when reading the kernel mimics +the operation of similar parts of the <tt>ntpd</tt> program fairly +closely, this can be useful when debugging problems with <tt> +ntpd</tt>.</p> + +<p>Note that <tt>tickadj</tt> should be run with some caution when +being used for the first time on different types of machines. The +operations which <tt>tickadj</tt> tries to perform are not +guaranteed to work on all Unix machines and may in rare cases cause +the kernel to crash.</p> + +<h4>Command Line Options</h4> + +<dl> +<dt><tt>-a <i>tickadj</i></tt></dt> + +<dd>Set the kernel variable <tt>tickadj</tt> to the value <i><tt> +tickadj</tt></i>specified.</dd> + +<dt><tt>-A</tt></dt> + +<dd>Set the kernel variable <tt>tickadj</tt> to an internally +computed "optimal" value.</dd> + +<dt><tt>-t <i>tick</i></tt></dt> + +<dd>Set the kernel variable <tt>tick</tt> to the value <i><tt> +tick</tt></i> specified.</dd> + +<dt><tt>-s</tt></dt> + +<dd>Set the kernel variable <tt>dosynctodr</tt> to zero, which +disables the hardware time-of-year clock, a prerequisite for +running the <tt>ntpd</tt> daemon under SunOS4.</dd> + +<dt><tt>-q</tt></dt> + +<dd>Normally, <tt>tickadj</tt> is quite verbose about what it is +doing. The <tt>-q</tt> flag tells it to shut up about everything +except errors.</dd> +</dl> + +<h4>Files</h4> + +<pre> /vmunix /unix -/dev/kmem</PRE> - -<H4> -Bugs</H4> -Fiddling with kernel variables at run time as a part of ordinary operations -is a hideous practice which is only necessary to make up for deficiencies -in the implementation of <TT>adjtime</TT> in many kernels and/or brokenness -of the system clock in some vendors' kernels. It would be much better if -the kernels were fixed and the <TT>tickadj</TT> program went away. -<HR> -<ADDRESS> -David L. Mills (mills@udel.edu)</ADDRESS> - -</BODY> -</HTML> +/dev/kmem +</pre> + +<h4>Bugs</h4> + +Fiddling with kernel variables at run time as a part of ordinary +operations is a hideous practice which is only necessary to make up +for deficiencies in the implementation of <tt>adjtime</tt> in many +kernels and/or brokenness of the system clock in some vendors' +kernels. It would be much better if the kernels were fixed and the +<tt>tickadj</tt> program went away. + +<hr> +<a href="index.htm"><img align="left" src="pic/home.gif" alt= +"gif"></a> +<address><a href="mailto:mills@udel.edu">David L. Mills +<mills@udel.edu></a></address> +</body> +</html> + |
