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PostPosted: Sun Nov 03, 2019 1:08 pm 
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This isn't a problem (I don't think), but it caught my eye. I have Tri-Backup programmed to do a backup every afternoon at 5pm. And it has been. Until today, when Daylight Saving Time ended and the clocks were turned back an hour. But, despite that my computer's clock was automatically changed by the Apple time server and shows the correct time, Tri-Backup executed the 5pm backup at 4pm. It says the next scheduled backup will be at 5pm tomorrow.

From where else but the computer's clock would Tri-Backup get time of day?

Again, not a problem; just mystified.

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PostPosted: Sun Nov 03, 2019 1:24 pm 
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Whoa, interesting, but every thought I have on that sort of dissolves on reflection.


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PostPosted: Sun Nov 03, 2019 7:09 pm 
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MikeHarrison wrote:
This isn't a problem (I don't think), but it caught my eye. I have Tri-Backup programmed to do a backup every afternoon at 5pm. And it has been. Until today, when Daylight Saving Time ended and the clocks were turned back an hour. But, despite that my computer's clock was automatically changed by the Apple time server and shows the correct time, Tri-Backup executed the 5pm backup at 4pm. It says the next scheduled backup will be at 5pm tomorrow.

From where else but the computer's clock would Tri-Backup get time of day?

Again, not a problem; just mystified.


I'd bet a ten spot that Tri-Backup is using a script that merely counts hourly increments by 12 instead of actually checking the system time. It's a lazy way of doing things, and if I'm right, your next backup will be at 4 PM physical time tomorrow, exactly 12 hours after the last backup task ran. Basically the script is "at set time when logged in and +12 hours repeating afterward".

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PostPosted: Mon Nov 04, 2019 2:24 am 
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ST must be right, but I bet Thierry would answer toot sweet.


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PostPosted: Tue Nov 05, 2019 5:35 am 
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Well, Tri-Backup dutifully returned to executing at 5pm on Monday and says it's scheduled to run at 5pm today.

I, too, considered for a moment whether it was simply counting hours, but it surprised us.

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PostPosted: Tue Nov 05, 2019 11:27 am 
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Ah, could it be preloading the next backup time in hours?


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PostPosted: Tue Nov 05, 2019 1:14 pm 
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Sounds like it only performs the GMT to local time calculation once a day. And then schedules the next day's task based on that calculation.


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PostPosted: Thu Nov 07, 2019 2:25 am 
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MonkeyBoy wrote:
Sounds like it only performs the GMT to local time calculation once a day. And then schedules the next day's task based on that calculation.


In other words, it syncs like Windows 10's clock does, i.e. almost never relative to any given session. It's an easy enough fix though on the developers' end.

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