xref: /freebsd/contrib/ntp/html/hints/sun4 (revision 02e9120893770924227138ba49df1edb3896112a)
1Notes on CPU clock oscillator tolerance with SunOS 4.1.1 and 4.1.3
2
3A bug in SunOS 4.1.1 results in the kernel time losing 1 microsecond
4per tick of the system clock. The bug was fixed (bugid 1094383) for
5SunOS 4.1.1 and corrected in SunOS 4.1.3. The easiest way to fix this
6is to replace the 4.1.1 binary clock.o with the corresponding 4.1.3
7binary. Without this change it is necessary to use the tickadj program
8included in this distribution with the -t 9999 option.
9
10The tickadj option will work in all cases except when the kernel has
11been modified to correct the CPU clock oscillator frequency using a
121-pps signal from a precision source. The bugfix must be installed for
13this wrinkle to work properly.
14
15Dave Mills (mills@udel.edu)
16