DoN. Nichols wrote:
According to Christopher Tidy :

DoN. Nichols wrote:


[ ... ]


Among the options to the "date" command, which can both read
and display the date, and set it, is:


[ ... man page extract ... ]


So -- yes, Sun does use the speed control.

Ah yes. Thanks Don. I read about this some time ago, but have never
actually used it. Now I wonder if the machine uses the speed control
automatically (this is mentioned in the chip data sheet) to correct
deviations of the clock?


For that, I would have to have access to the source code of the
kernel. I've got it for OpenBSD, and can easily get it for most other
BSD flavors, as well as for most linux flavors, but I don't have it for
Solaris (though I understand that it is now available for Solaris 10).

But I believe that it is. Take a look at another excerpt --
this time from the "xntpd" daemon used for maintaining system clocks in
synchronization:


================================================== ====================
driftfile filename

Specifies the name of the file used to record the fre-
quency offset of the local clock oscillator. If the file
exists, it is read at startup in order to set the ini-
tial frequency offset. Then the file is updated once per
hour with the current offset computed by the daemon. If
the file does not exist or this command is not given,
the initial frequency offset is assumed to be zero. In
this case, it may take some hours for the frequency to
stabilize and the residual timing errors to subside. The
file contains a single floating point value equal to the
offset in parts-per-million (ppm). The file is updated
by first writing the current drift value into a tem-
porary file and then using rename(2) to replace the old
version. This implies that xntpd must have write permis-
sion for the directory the drift file is located in, and
that file system links, symbolic or otherwise, should
probably be avoided.
================================================== ====================

So -- it would appear that it is tuning the clock chip to track
the master system.

Enjoy,
DoN.

Thanks for the interesting information. It does explain, I think, why
Suns keep pretty good time compared to many PCs!

Chris