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Impact of Daylight Savings Time Changes?
jason718 writes "With the pending changes to U.S. Daylight Savings Time, what impact will those changes have to existing systems and their applications? Are some operating systems more open than others with regard to the configuration of Daylight Savings Time start and end dates, or will we need yet another update or patch to modify the internal calendar?"
With over 800 comments, I thought that's enough to get an idea of its impact and suggestions to deal with it.
Rock that crushes, Paper & Scissors that don't matter.
(Until we follow you guys)
We've always been at war with Eurasia.
An article from Colorado's legislature suggests that the primary complaint from farmers is that "most agricultural activities are based on daylight hours as opposed to clock hours, and crops and livestock maintain their schedules regardless of the time reflected on the clock."
Because the farmers and their families would still have to work with their product during certain margins of the day to accomdate the plants, they would have to readjust their schedules to do non-farm things like shop for food, meet with a bank, etc.
In the case of agribusiness, they would have to readjust the schedules of their employees.
It's Daylight Saving Time, not Daylight Savings Time.
As long the operating system can handle both local time and Coordinated Universal Time, it should not be any problem. If the program saves every time in UTC, and when displayed, convert it to local time, the user should not need to be worried. As a European citizen we all have DST, and we manage easly, so why shouldn't those in the US manage too?
------- In the end there are no begining
Of course, the countries of the world that do change their clocks don't change their clocks at the same time. The EU starts DST on the last Sunday of March whereas we (currently) start ours on the first Sunday of April. Currently, we both end ours on the last Sunday of October.
If we're going to change how we handle DST, I'd recommend that we match the EU. I know that the idea of following the EU's lead is anathema to many of us, but hey, it's a small sacrifice and shows that we're willing to make compromises every so often.
Ben Hocking
Need a professional organizer?
Cisco devices, both IOS and CatOS based, use the 'summertime' command to compensate for daylight saving time (example [cisco.com]). This means that a change in the DST setup would force you to upgrade code.
Or at least it would force you to study the command reference a bit better, and find the second optional form of the command that allows you to specify the beginning and end of summertime.
That would mean you require only a configuration change, and not a code upgrade.
But of course you would need to read the manual...
Relax -- your investment in atomic clocks (really radio-controlled) is safe :) They get DST from the master clock already.
All of the radio-controlled or "atomic" clocks work on the same idea -- they receive a time signal from a low-frequency transmitter (60kHz in the US). The device will typically set an internal quartz clock from the received time code. The time reference signal is strongest at night, so it's typical for these clocks to set themselves at 2 or 3 am (local time). Some newer designs will set whenever the signal strength is high enough for a good read. This redundancy makes for a very reliable device.
The time code contains, among other things, a flag indicating whether DST is in effect. So -- when (if?) this change to the DST rules goes into effect, the folks who run the transmitter will change the flag at the proper moment, and the next time your clock reads the signal, et viola! it reads DST.
The radio station broadcasting the time code in the US is WWVB, and it is managed by NIST. The WWBV system is really an elegant design, involving a wonderful mixture of old and new technology. Check it out:
http://tf.nist.gov/stations/wwvb.htm
By the way, there are 4 other time zones east of US Eastern. The Atlantic time zone, for example applies in Nova Scotia. There are also similar time reference broadcasts in the EU, Russia, and Australia. There might also be one in China - but I've never needed to look that one up. I'm sure that will change one day soon.
Who? Whom? It might help your career if you know the difference.
http://www.ku.edu/~edit/whom.html
Who refers to a subject, whom refers to an object.
You should have said: "Who is fooling whom?"
I offer this tip merely to help you advance your career, not to be a national socialist.
A slashdotter who didn't build his own computer is like a Jedi who didn't build his own lightsaber.
You don't need to reboot.
If you are not sure about cron rereading the timezone:
- read the man page
- ask someone who knows (mailinglist?)
If in doubt, just do a "/etc/init.d/crond restart"
that should do the trick.
we need an "-1 Plain wrong" moderation option!
Before you start doing the LED lighting conversion look into high energy capacitors (so-called "Supercaps"). I haven't run the numbers, but my guess is they aren't at a good price point yet. A design built around them would have the advantage of zero maintenance, and a working lifespan of about 10 years.