In message <[EMAIL PROTECTED]>, Peter Jeremy writes:
>On 2000-Feb-03 20:11:57 +1100, Bruce Evans <[EMAIL PROTECTED]> wrote:
>> ntp is
>>doing well if it falls back to another method after the syscalls fail.
>
>ntpd iterates (at runtime) through all the possible scheduling
>mechanisms that were enabled at compile time, until one works. These
>are (in order) SetPriorityClass() (LoseNT only), sched_setscheduler(),
>rtprio(), nice(), setpriority(). If all these fail, it will log a
>message that it couldn't improve it's priority - in which case it will
>still function, but probably won't be as accurate. (ntpd is probably
>a special case, in that the P1003.1b functions aren't essential to it,
>they just improve its operation).
Actually none of this seems to have much effect on it's performance
since we timestamp packets in the kernel on input and the chances
of being preempted between constructing the output packet and sending
it is epsilon.
--
Poul-Henning Kamp FreeBSD coreteam member
[EMAIL PROTECTED] "Real hackers run -current on their laptop."
FreeBSD -- It will take a long time before progress goes too far!
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