Is your clock in sync? (USA)

https://www.time.gov/

My clock is ticking in unison with that clock.

On 2020-07-11 3:07 p.m., John Doe wrote:
https://www.time.gov/

My clock is ticking in unison with that clock.



Yeppers, Within a half second. :-)

Nice page, and handy, Thanks.

Rene

On 7/11/20 4:07 PM, this is what John Doe wrote:
https://www.time.gov/

My clock is ticking in unison with that clock.

The page says mine is off by 40 seconds, but my clock flips to the next minute the same time the web page does, so I'm not sure what they
mean other than maybe the rtc on the motherboard.

Al

Big Al wrote:
On 7/11/20 4:07 PM, this is what John Doe wrote:
https://www.time.gov/

My clock is ticking in unison with that clock.

The page says mine is off by 40 seconds, but my clock flips to the next
minute the same time the web page does, so I'm not sure what they mean
other than maybe the rtc on the motherboard.

Al

The RTC is not typically accessed while the OS runs.

It's accessed at some point, to transfer the "software time"
to the RTC for safe keeping. The interface is too slow for any
practical purpose. RTC has 1 second resolution. Hardware
clock (part of software time system) is 100ns or so.

Startup
RTC -- software clock # prime software clock
...
software clock -- RTC # save software clock
shutdown

The RTC clock (32768Hz, ripple divider to 1 second) and
the hardware clock (100MHz BCLK or higher), they drift at
different rates because they use different xtals. Which
means the drift when you shutdown, is different than
the drift rate while the box runs.

Windows time synchronizes infrequently, and so an error
can accumulate between sync points. A period of a week
is selected, to avoid overloading timeservers. Timeservers
(should) have anti-hammering provisions - if you set the
sync interval to one minute, a good server will cut you off.
The pool.org server might not, because it's a pool and
has some form of load balancer. I don't personally
encourage the usage of pool.org . Use one of the government
ones, leave it set to a week etc.

And time servers have been off by as much as 20 minutes.
If you're getting complaints from your OS that "the clock is off",
it's quite likely to be true. When an official server is "off",
it can just as easily be a "whoa boy" sized error :-) They won't
be off by 3 nanoseconds. Just go whole hog and shoot for 20 minutes.
I have no idea how the thing can go off by 20 minutes. Some
clever software calc of some sort (atomic clock consolidation?).
It'll probably turn out, the whole thing is based on a battery
operated ticky clock on the control room wall :-)

Paul

On 11.07.20 22:33, Rene Lamontagne wrote:
On 2020-07-11 3:07 p.m., John Doe wrote:
https://www.time.gov/

My clock is ticking in unison with that clock.



Yeppers, Within a half second. :-)

Nice page, and handy, Thanks.

Rene

my clock is 0.04 seconds off.

On 2020-07-11 5:22 p.m., Paul wrote:
Big Al wrote:
On 7/11/20 4:07 PM, this is what John Doe wrote:
https://www.time.gov/

My clock is ticking in unison with that clock.

The page says mine is off by 40 seconds, but my clock flips to the
next minute the same time the web page does, so I'm not sure what they
mean other than maybe the rtc on the motherboard.

Al

The RTC is not typically accessed while the OS runs.

It's accessed at some point, to transfer the "software time"
to the RTC for safe keeping. The interface is too slow for any
practical purpose. RTC has 1 second resolution. Hardware
clock (part of software time system) is 100ns or so.

Â*Â*Â* Startup
Â*Â*Â* RTC -- software clockÂ*Â* # prime software clock
Â*Â*Â* ...
Â*Â*Â* software clock -- RTCÂ*Â* # save software clock
Â*Â*Â* shutdown

The RTC clock (32768Hz, ripple divider to 1 second) and
the hardware clock (100MHz BCLK or higher), they drift at
different rates because they use different xtals. Which
means the drift when you shutdown, is different than
the drift rate while the box runs.

Windows time synchronizes infrequently, and so an error
can accumulate between sync points. A period of a week
is selected, to avoid overloading timeservers. Timeservers
(should) have anti-hammering provisions - if you set the
sync interval to one minute, a good server will cut you off.
The pool.org server might not, because it's a pool and
has some form of load balancer. I don't personally
encourage the usage of pool.org . Use one of the government
ones, leave it set to a week etc.

And time servers have been off by as much as 20 minutes.
If you're getting complaints from your OS that "the clock is off",
it's quite likely to be true. When an official server is "off",
it can just as easily be a "whoa boy" sized error :-) They won't
be off by 3 nanoseconds. Just go whole hog and shoot for 20 minutes.
I have no idea how the thing can go off by 20 minutes. Some
clever software calc of some sort (atomic clock consolidation?).
It'll probably turn out, the whole thing is based on a battery
operated ticky clock on the control room wall :-)

Â*Â* Paul

Damn, my clock drifted since I checked it earlier at 3:33 today it was
out by .321 seconds, now its out by .971 seconds.
What to do, What to do? Sigh. :-)

Rene

On 12/07/2020 00.22, Paul wrote:

....

Windows time synchronizes infrequently, and so an error
can accumulate between sync points. A period of a week
is selected, to avoid overloading timeservers. Timeservers
(should) have anti-hammering provisions - if you set the
sync interval to one minute, a good server will cut you off.
The pool.org server might not, because it's a pool and
has some form of load balancer. I don't personally
encourage the usage of pool.org . Use one of the government
ones, leave it set to a week etc.

Wow, one week. I must be spoiled by tools like ntpd in Linux, keeps the
clock accurate continuously within milliseconds using the pool.

--
Cheers, Carlos.

On 12/07/2020 01.35, Carlos E.R. wrote:
On 12/07/2020 00.22, Paul wrote:

...

Windows time synchronizes infrequently, and so an error
can accumulate between sync points. A period of a week
is selected, to avoid overloading timeservers. Timeservers
(should) have anti-hammering provisions - if you set the
sync interval to one minute, a good server will cut you off.
The pool.org server might not, because it's a pool and
has some form of load balancer. I don't personally
encourage the usage of pool.org . Use one of the government
ones, leave it set to a week etc.

Wow, one week. I must be spoiled by tools like ntpd in Linux, keeps the
clock accurate continuously within milliseconds using the pool.


I forgot. In a Windows Domain with Active Directory, keeping all the
machines in sync is crucial. A small error and you simply can not login
(Kerberos). It doesn't matter if the clock is correct, but all the
machines need have the same time.

--
Cheers, Carlos.

Rene Lamontagne wrote:
On 2020-07-11 5:22 p.m., Paul wrote:
Big Al wrote:
On 7/11/20 4:07 PM, this is what John Doe wrote:
https://www.time.gov/

My clock is ticking in unison with that clock.

The page says mine is off by 40 seconds, but my clock flips to the
next minute the same time the web page does, so I'm not sure what
they mean other than maybe the rtc on the motherboard.

Al

The RTC is not typically accessed while the OS runs.

It's accessed at some point, to transfer the "software time"
to the RTC for safe keeping. The interface is too slow for any
practical purpose. RTC has 1 second resolution. Hardware
clock (part of software time system) is 100ns or so.

Startup
RTC -- software clock # prime software clock
...
software clock -- RTC # save software clock
shutdown

The RTC clock (32768Hz, ripple divider to 1 second) and
the hardware clock (100MHz BCLK or higher), they drift at
different rates because they use different xtals. Which
means the drift when you shutdown, is different than
the drift rate while the box runs.

Windows time synchronizes infrequently, and so an error
can accumulate between sync points. A period of a week
is selected, to avoid overloading timeservers. Timeservers
(should) have anti-hammering provisions - if you set the
sync interval to one minute, a good server will cut you off.
The pool.org server might not, because it's a pool and
has some form of load balancer. I don't personally
encourage the usage of pool.org . Use one of the government
ones, leave it set to a week etc.

And time servers have been off by as much as 20 minutes.
If you're getting complaints from your OS that "the clock is off",
it's quite likely to be true. When an official server is "off",
it can just as easily be a "whoa boy" sized error :-) They won't
be off by 3 nanoseconds. Just go whole hog and shoot for 20 minutes.
I have no idea how the thing can go off by 20 minutes. Some
clever software calc of some sort (atomic clock consolidation?).
It'll probably turn out, the whole thing is based on a battery
operated ticky clock on the control room wall :-)

Paul

Damn, my clock drifted since I checked it earlier at 3:33 today it was
out by .321 seconds, now its out by .971 seconds.
What to do, What to do? Sigh. :-)

Rene

Ah, a time fetish ?

GPS discipline.

And either the hardware comes with a downloadable
software to tie the GPS time into the computer,
or you search for applications yourself. I don't
see GPS in any of the screenshots here, but it might
be there.

https://www.meinbergglobal.com/english/sw/ntp.htm

For software, maybe NFS servers in Linux, might
appreciate tight time keeping. I don't know if
Windows shares particularly care.

Way back when, it would have cost a thousand
bucks for this, but it's a lot cheaper now to
discipline a PC.

Hold your GPS near a window, to get some signal.

Paul

On 2020-07-11 7:26 p.m., Paul wrote:
Rene Lamontagne wrote:
On 2020-07-11 5:22 p.m., Paul wrote:
Big Al wrote:
On 7/11/20 4:07 PM, this is what John Doe wrote:
https://www.time.gov/

My clock is ticking in unison with that clock.

The page says mine is off by 40 seconds, but my clock flips to the
next minute the same time the web page does, so I'm not sure what
they mean other than maybe the rtc on the motherboard.

Al

The RTC is not typically accessed while the OS runs.

It's accessed at some point, to transfer the "software time"
to the RTC for safe keeping. The interface is too slow for any
practical purpose. RTC has 1 second resolution. Hardware
clock (part of software time system) is 100ns or so.

Â*Â*Â*Â* Startup
Â*Â*Â*Â* RTC -- software clockÂ*Â* # prime software clock
Â*Â*Â*Â* ...
Â*Â*Â*Â* software clock -- RTCÂ*Â* # save software clock
Â*Â*Â*Â* shutdown

The RTC clock (32768Hz, ripple divider to 1 second) and
the hardware clock (100MHz BCLK or higher), they drift at
different rates because they use different xtals. Which
means the drift when you shutdown, is different than
the drift rate while the box runs.

Windows time synchronizes infrequently, and so an error
can accumulate between sync points. A period of a week
is selected, to avoid overloading timeservers. Timeservers
(should) have anti-hammering provisions - if you set the
sync interval to one minute, a good server will cut you off.
The pool.org server might not, because it's a pool and
has some form of load balancer. I don't personally
encourage the usage of pool.org . Use one of the government
ones, leave it set to a week etc.

And time servers have been off by as much as 20 minutes.
If you're getting complaints from your OS that "the clock is off",
it's quite likely to be true. When an official server is "off",
it can just as easily be a "whoa boy" sized error :-) They won't
be off by 3 nanoseconds. Just go whole hog and shoot for 20 minutes.
I have no idea how the thing can go off by 20 minutes. Some
clever software calc of some sort (atomic clock consolidation?).
It'll probably turn out, the whole thing is based on a battery
operated ticky clock on the control room wall :-)

Â*Â*Â* Paul

Damn, my clock drifted since IÂ* checked it earlier at 3:33Â* today it
was out by .321 seconds, now its out by .971 seconds.
What to do, What to do?Â*Â* Sigh. :-)

Rene

Ah, a time fetish ?

GPS discipline.

And either the hardware comes with a downloadable
software to tie the GPS time into the computer,
or you search for applications yourself. I don't
see GPS in any of the screenshots here, but it might
be there.

https://www.meinbergglobal.com/english/sw/ntp.htm

For software, maybe NFS servers in Linux, might
appreciate tight time keeping. I don't know if
Windows shares particularly care.

Way back when, it would have cost a thousand
bucks for this, but it's a lot cheaper now to
discipline a PC.

Hold your GPS near a window, to get some signal.

Â*Â* Paul

Nah, just bored. :-)

Rene

On 2020-07-11, Carlos E.R. wrote:
On 12/07/2020 01.35, Carlos E.R. wrote:
On 12/07/2020 00.22, Paul wrote:

...

Windows time synchronizes infrequently, and so an error
can accumulate between sync points. A period of a week
is selected, to avoid overloading timeservers. Timeservers
(should) have anti-hammering provisions - if you set the
sync interval to one minute, a good server will cut you off.
The pool.org server might not, because it's a pool and
has some form of load balancer. I don't personally
encourage the usage of pool.org . Use one of the government
ones, leave it set to a week etc.

Wow, one week. I must be spoiled by tools like ntpd in Linux, keeps the
clock accurate continuously within milliseconds using the pool.


I forgot. In a Windows Domain with Active Directory, keeping all the
machines in sync is crucial. A small error and you simply can not login
(Kerberos). It doesn't matter if the clock is correct, but all the
machines need have the same time.

Must also use the same time server. I recall one version of windows
had the time server defaulted to a ms time server; the good thing was
that one can change the time server to any available sever.

Looks like win 10 2004 does not allow changing the server from
default 'time.nist.gov'. AND no longer able to change the time server
to the Fort Collins to be in sync with my 'atomic' wall clocks.

On 12/07/2020 03.22, lew wrote:
On 2020-07-11, Carlos E.R. wrote:
On 12/07/2020 01.35, Carlos E.R. wrote:
On 12/07/2020 00.22, Paul wrote:

...

Windows time synchronizes infrequently, and so an error
can accumulate between sync points. A period of a week
is selected, to avoid overloading timeservers. Timeservers
(should) have anti-hammering provisions - if you set the
sync interval to one minute, a good server will cut you off.
The pool.org server might not, because it's a pool and
has some form of load balancer. I don't personally
encourage the usage of pool.org . Use one of the government
ones, leave it set to a week etc.

Wow, one week. I must be spoiled by tools like ntpd in Linux, keeps the
clock accurate continuously within milliseconds using the pool.


I forgot. In a Windows Domain with Active Directory, keeping all the
machines in sync is crucial. A small error and you simply can not login
(Kerberos). It doesn't matter if the clock is correct, but all the
machines need have the same time.

Must also use the same time server.

The Windows Domain Server machine acts as time server for the domain.

I recall one version of windows
had the time server defaulted to a ms time server; the good thing was
that one can change the time server to any available sever.

Looks like win 10 2004 does not allow changing the server from
default 'time.nist.gov'. AND no longer able to change the time server
to the Fort Collins to be in sync with my 'atomic' wall clocks.



--
Cheers, Carlos.

On 11/07/2020 23:29, Sjouke Burry wrote:
On 11.07.20 22:33, Rene Lamontagne wrote:
On 2020-07-11 3:07 p.m., John Doe wrote:
https://www.time.gov/

My clock is ticking in unison with that clock.



Yeppers, Within a half second.Â* :-)

Nice page, and handy,Â* Thanks.

Rene

my clock is 0.04 seconds off.

You beat me:
my clock is off by: +0.050 s

--
Brian Gregory (in England).

On 12/07/2020 02:22, lew wrote:
Must also use the same time server.

I generally use at least 4 NTP servers.

I run Meinberg NTP client, the one built in to Windows is just a toy.

--
Brian Gregory (in England).

Rene Lamontagne wrote:
On 2020-07-11 7:26 p.m., Paul wrote:
Rene Lamontagne wrote:
On 2020-07-11 5:22 p.m., Paul wrote:
Big Al wrote:
On 7/11/20 4:07 PM, this is what John Doe wrote:
https://www.time.gov/

My clock is ticking in unison with that clock.

The page says mine is off by 40 seconds, but my clock flips to the
next minute the same time the web page does, so I'm not sure what
they mean other than maybe the rtc on the motherboard.

Al

The RTC is not typically accessed while the OS runs.

It's accessed at some point, to transfer the "software time"
to the RTC for safe keeping. The interface is too slow for any
practical purpose. RTC has 1 second resolution. Hardware
clock (part of software time system) is 100ns or so.

Startup
RTC -- software clock # prime software clock
...
software clock -- RTC # save software clock
shutdown

The RTC clock (32768Hz, ripple divider to 1 second) and
the hardware clock (100MHz BCLK or higher), they drift at
different rates because they use different xtals. Which
means the drift when you shutdown, is different than
the drift rate while the box runs.

Windows time synchronizes infrequently, and so an error
can accumulate between sync points. A period of a week
is selected, to avoid overloading timeservers. Timeservers
(should) have anti-hammering provisions - if you set the
sync interval to one minute, a good server will cut you off.
The pool.org server might not, because it's a pool and
has some form of load balancer. I don't personally
encourage the usage of pool.org . Use one of the government
ones, leave it set to a week etc.

And time servers have been off by as much as 20 minutes.
If you're getting complaints from your OS that "the clock is off",
it's quite likely to be true. When an official server is "off",
it can just as easily be a "whoa boy" sized error :-) They won't
be off by 3 nanoseconds. Just go whole hog and shoot for 20 minutes.
I have no idea how the thing can go off by 20 minutes. Some
clever software calc of some sort (atomic clock consolidation?).
It'll probably turn out, the whole thing is based on a battery
operated ticky clock on the control room wall :-)

Paul

Damn, my clock drifted since I checked it earlier at 3:33 today it
was out by .321 seconds, now its out by .971 seconds.
What to do, What to do? Sigh. :-)

Rene

Ah, a time fetish ?

GPS discipline.

And either the hardware comes with a downloadable
software to tie the GPS time into the computer,
or you search for applications yourself. I don't
see GPS in any of the screenshots here, but it might
be there.

https://www.meinbergglobal.com/english/sw/ntp.htm

For software, maybe NFS servers in Linux, might
appreciate tight time keeping. I don't know if
Windows shares particularly care.

Way back when, it would have cost a thousand
bucks for this, but it's a lot cheaper now to
discipline a PC.

Hold your GPS near a window, to get some signal.

Paul

Nah, just bored. :-)

Rene

Mine is off by 2.7 seconds. What a slob.

But that's after six days.

Paul