On Wed, Oct 7, 2009 at 1:34 PM, Arnold Schekkerman
<[email protected]> wrote:
...
> How stable is your internet connection
rock solid business-class 6x1.5 DSL ...
> and how heavy is it loaded with traffic?
while doing this particular setup, not at all ...
testing further, i've set up two identical servers. same mobo (Asus
M387A-CM), BIOS version (v1903), CPU (AMD Phenom II X4 2.6GHz), OS
(opensuse 11.1), kernel version (2.6.27.29-0.1).
the difference between the 2 is that server (1) is running a Xen Dom0
kernel, and server (2) is running the default, non-Xen kernel.
both machines are setup to use NTP for time services. i've
identically config'd ntp, using 3 low-latency Stratum 2 servers.
cat /etc/ntp.conf
restrict default nomodify notrap noquery
restrict 127.0.0.1
restrict 192.168.1.0 mask 255.255.255.0 notrust nomodify notrap
server ntp1.stsn.net
server clock.develooper.com
server 192.83.249.28
driftfile /var/lib/ntp/drift/ntp.drift
logfile /var/log/ntpd/ntp.log
statsdir /var/log/ntpd/
filegen peerstats file peerstats type day enable
filegen loopstats file loopstats type day enable
filegen clockstats file clockstats type day enable
i restarted ntpd on both servers at the same time, and waited 2 hours.
server (2) is synced, with low jitter and offset to stratum3; server
(1) hasn't managed to make it out of stratum 16 ...
(1)
uname -a
Linux server02 2.6.27.29-0.1-xen #1 SMP 2009-08-15 17:53:59 +0200
x86_64 x86_64 x86_64 GNU/Linux
cat /sys/devices/system/clocksource/clocksource0/available_clocksource
xen jiffies
cat /sys/devices/system/clocksource/clocksource0/current_clocksource
jiffies
cat /proc/sys/xen/independent_wallclock
1
service ntp stop && sntp -P no -r us.pool.ntp.org && service ntp start && date
Shutting down network time protocol daemon (NTPD)
done
Starting network time protocol daemon (NTPD)
done
Wed Oct 7 16:28:44 PDT 2009
...
...
date
Wed Oct 7 18:50:21 PDT 2009
ntpq -p -c rv
...
stratum=16, precision=-8, rootdelay=0.000, rootdispersion=10.485,
...
remote refid st t when poll reach delay
offset jitter
==============================================================================
*time-sj.stsn.ne 198.60.22.240 2 u 57 64 377 27.612 -1390.8
658.318
+clock-a.develoo 204.123.2.72 2 u 15 64 377 28.280 -1478.4
652.232
+zorro.sf-bay.or 216.218.254.202 2 u 52 64 377 17.287 -1395.2
650.788
(2)
uname -a
Linux server03 2.6.27.29-0.1-default #1 SMP 2009-08-15 17:53:59 +0200
x86_64 x86_64 x86_64 GNU/Linux
cat /sys/devices/system/clocksource/clocksource0/available_clocksource
hpet acpi_pm jiffies tsc
cat /sys/devices/system/clocksource/clocksource0/current_clocksource
hpet
service ntp stop && sntp -P no -r us.pool.ntp.org && service ntp start && date
Shutting down network time protocol daemon (NTPD)
done
Starting network time protocol daemon (NTPD)
done
Wed Oct 7 16:28:46 PDT 2009
...
...
date
Wed Oct 7 18:51:07 PDT 2009
ntpq -p -c rv
...
stratum=3, precision=-20, rootdelay=47.377, rootdispersion=14.367,
...
remote refid st t when poll reach delay
offset jitter
==============================================================================
*time-sj.stsn.ne 198.60.22.240 2 u 64 64 377 28.779 -4.716
2.679
+clock-b.develoo 204.123.2.72 2 u 59 64 377 26.669 -0.886
3.322
+zorro.sf-bay.or 216.218.254.202 2 u 51 64 377 16.563 -0.645
2.906
finally, i swapped the kernel-default & kernel-xen between the two
machines, and saw the same results.
if i understand the above correctly, this says "problem with Xen" to me ...
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