FBSD 5.5 and software timers

Michael Scheidell scheidell at secnap.net
Tue Jul 25 17:10:58 UTC 2006

Tim Kientzle wrote:
> M. Warner Losh wrote:
>> In message: <B3BCAF4246A8A84983A80DAB50FE72424C6970 at secnap2.secnap.com>
>>             "Michael Scheidell" <scheidell at secnap.net> writes:
>> : > I presume the servers are all stable (ie not stepping) and : > 
>> have a reasonably low delay.  If so, I suspect your ntpd PLL : > has 
>> locked up. I've seen problems with some versions of ntpd : : 20 
>> different machines?
>> That would strongly imply a poor choice of upstream server.
> It might also help to set up 1 machine as
> your NTP master.  Have it sync to the upstream
> servers and have the rest of your machines
> sync to it.  This won't solve the problem,
> but might make it easier to solve (once your
> NTP master is stable, the rest should follow).
Except that all 20 are on different physical networks, one in a 
different content.
I went back and looked at out 4.11 systems, and didn't see any 'time 
reset' errors.

Internally, here at this physical location, we do have one master ntp 
server, pulling from (3) servers, not two.
All internal systems then pull from this one master.

> You can experiment with different upstream
> servers, different network settings, different
> NTP settings, etc.
only ntp setting that helped was the -x option (adjust once, slew 128m 
max each other time)
One external box is now 30 seconds out of sync (after 24 hours)

Again, ntp problem is one thing, but what about the nanosleep() issue?
5.4 worked fine, 5.5 has problems.

Did something change in 5.5 with clock() or nanosleep()?
Its not documented in the readme for 5.5.

Michael Scheidell, CTO
SECNAP Network Security / www.secnap.com
scheidell at secnap.net  / 1+561-999-5000, x 1131

More information about the freebsd-hackers mailing list