X9SCM-F-O clock drift +1 second into the future when ntp running?
Hello,
I migrated from an X7SPA to an X9SCM-F-O and now gpsd/ntp no longer sync with my GPS unit:
http://www.amazon.com/GlobalSat-BU-353-USB-GPS-Receiver/dp/B000PKX2KA
I did some digging and it looks like the system clock on this motherboard with the latest BIOS (2.00a) runs 1 second too fast when comparing to other NTP-synchronized machines.
When comparing the clock on this vs. an atomic clock, the system clock is ~1 second faster, which is probably why the GPS has problems syncing.
Is this a faulty motherboard clock or is this an issue with Ivy Bridge (I am using an E3-1200 V2 CPU) with the X9SCM-F-O and BIOS 2.00a?
DMI Info:
Handle 0x0000, DMI type 0, 24 bytes
BIOS Information
Vendor: American Megatrends Inc.
Version: 2.0a
Release Date: 06/08/2012
Address: 0xF0000
Runtime Size: 64 kB
ROM Size: 8192 kBNTP problem:
Problem, the x127 for the GPS:
$ ntpq -pn
remote refid st t when poll reach delay offset
jitter
============================================================================
==
x127.127.28.0 .GPS. 0 l 11 16 377 0.000 0.363
100.414
*204.235.61.9 128.174.38.133 2 u 48 64 37 48.716 -985.27
326.767
+184.105.192.247 216.218.254.202 2 u 43 64 37 90.902 -987.55
332.766
+50.7.247.114 85.114.26.194 2 u 42 64 37 158.445 -985.19
330.627
+69.65.40.29 209.51.161.238 2 u 43 64 37 47.733 -984.50
329.232Any idea why it consistently has a ~1 second offset? Is there a good way to fix this?
Before, on the X7SPA I ran gpsd+ntp for years without any issues, it synchronized perfectly. Is this a BIOS issue? Kernel problem or HW issue?
$ cat /sys/devices/system/clocksource/clocksource0/current_clocksource tsc
Full output:
# adjtimex -p
mode: 0
offset: 0
frequency: 1523449
maxerror: 16000000
esterror: 16000000
status: 8257
time_constant: 3
precision: 1
tolerance: 32768000
tick: 10015
raw time: 1341673069s 873569969us = 1341673069.873569969
return value = 5After 5-10 minutes without ntpd running, the clock had drifted -2.27 seconds the other direction..
# ntpdate time.nist.gov 7 Jul 11:03:32 ntpdate[374]: step time server 128.138.140.44 offset -2.273077 sec
Justin.
-----Original Message-----
From: Justin Piszcz [mailto:[email protected]]
Sent: Saturday, July 07, 2012 11:12 AM
To: [email protected]; [email protected]
Subject: X9SCM-F-O clock drift +1 second into the future when ntp running?
Hello,
I migrated from an X7SPA to an X9SCM-F-O and now gpsd/ntp no longer sync with my GPS unit:
http://www.amazon.com/GlobalSat-BU-353-USB-GPS-Receiver/dp/B000PKX2KA
I did some digging and it looks like the system clock on this motherboard with the latest BIOS (2.00a) runs 1 second too fast when comparing to other NTP-synchronized machines.
--
I've done some more reading and what I've found is anything over 500ppm ntp cannot correct for; so is this would be a bad crystal/chip or is there something else wrong here?
Supermicro X9SCM: (see the error_ppm) is all over the map:
# adjtimex -a
--- current --- -- suggested --
cmos time system-cmos error_ppm tick freq tick freq
1341688282 -0.731743
1341688292 -0.731619 12.4 9993 3497075
1341688302 -0.747186 -1556.7 9993 3497075 10009 659788
1341688312 -0.747117 6.9 9993 3497075 9993 3045513
1341688322 -0.747099 1.8 9993 3497075 9993 3378325
1341688332 -0.762636 -1553.7 9993 3378325 10009 344163
1341688342 -0.762650 -1.4 9993 3378325 9993 3470512
1341688352 -0.778221 -1557.1 9993 3378325 10009 566038# adjtimex -a
--- current --- -- suggested --
cmos time system-cmos error_ppm tick freq tick freq
1341688564 -0.591964
1341688574 -0.575373 1659.1 10009 566038
1341688584 -0.574515 85.8 10009 566038 10008 1497763
1341688594 -0.558007 1650.8 10009 566038 9992 3789738
1341688604 -0.537084 2092.3 10009 566038 9988 1071325
1341688614 -0.568492 -3140.8 9988 1071325 10019 3744100
1341688624 -0.568774 -28.2 9988 1071325 9988 2919762
1341688634 -0.584618 -1584.4 9988 1071325 10004 49663Old MSI motherboard (Pentium 4-- see how the PPM is roughly in the same range)
# adjtimex -a
WARNING: CMOS time is 30.02 min ahead of system clock
--- current --- -- suggested -- cmos time system-cmos error_ppm tick freq tick freq 1341690163 -1800.416735 1341690173 -1800.417111 -37.6 9996 2365500 1341690183 -1800.417499 -38.7 9996 2365500 9996 4904456 1341690193 -1800.417894 -39.5 9996 2365500 9996 4956019 1341690203 -1800.418297 -40.3 9996 2365500 9996 5007582 1341690213 -1800.418308 -1.0 9996 5007582 9996 5074664 1341690223 -1800.418327 -1.9 9996 5007582 9996 5134039 1341690233 -1800.418353 -2.6 9996 5007582 9996 5179351
Found this:
http://compgroups.net/comp.protocols.time.ntp/hopelessly-broken-clock/490495
set clocksource=hpet for boot options instead of TSC
Did not make any difference, still all over the map:
# adjtimex -a
--- current --- -- suggested --
cmos time system-cmos error_ppm tick freq tick freq
1341690087 0.238485
1341690097 0.240449 196.4 10015 1475154
1341690107 0.257408 1695.9 10015 1475154 9998 1744166
1341690117 0.274176 1676.8 10015 1475154 9998 2995729
1341690127 0.290927 1675.1 10015 1475154 9998 3106666
1341690137 0.291142 21.5 9998 3106666 9998 1697291
1341690147 0.275783 -1535.9 9998 3106666 10013 5458916
1341690157 0.276029 24.6 9998 3106666 9998 1494166Has anyone seen anything like this before?
I checked all of the BIOS options, did not see anything out of the ordinary here..
Justin.