Difference between revisions of "Talk:Time"

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==<s>Some people seriously discuss turning this wiki into the personal blog</s>==
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== Using UTC in Windows can cause some problems  ==
Gog, why is it you're so determined to delete this?
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I'm working on it and its a valid topic.
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There's a fair amount of evidence to show that when you run Windows with UTC time, things get hairy:
  
johnea
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* [http://www.cl.cam.ac.uk/~mgk25/mswish/ut-rtc.html] See the Current Support Status In Windows section
:because it reads like a blog and its kinda wierd. compare it to the rest of the stuff. how to install this that BAM PHILOSOPHICAL BREAKTHROUGH
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* [http://blogs.msdn.com/b/oldnewthing/archive/2004/09/02/224672.aspx] Raymond Chen has a nice writeup
  
:Ya know, a lot of the stuff on this wiki is just plain out of date.
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Most people shouldn't get touched by this, but I know plenty of times I've been bugged (namely, every single debugger reads the BIOS clock and attempts to not de-botch itself) when using Windows with UTC time. In my experience, Windows 8 also will force BIOS time into being Un-DST adjusted Localtime. Dangerous!
  
Don't you think it would be more productive to try to find stuff that just doesn't even apply to the current arch system and update or delete that.
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--[[User:Indrora|Indrora]] ([[User talk:Indrora|talk]]) 05:58, 31 October 2012 (UTC)
 
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Take a look at Arch64, there are 3 or 4 different ways of implimenting this and there is no contextual information on how or when these work together or when they are mutually exclusive. For instance, the "Current State of Arch64 Development" which is 2 years old.
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A lot of times things are at first done by individuals, then eventually some variation on the theme is included in the standard distribution. A wiki article describes the original work, but it's never updated to indicate that this is all build-in now.
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There's a lot of specific information, but much of it is not current, and almost none of it is tied together.
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It seems a lot of work could go into making the wiki more organized and relating the various topics to each other.
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This would make a resource for arch users new and old.
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With all of this lacking in the current documentation, I don't understand the need to be some kind of self expression censor.
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this article started when I was investigating posix time and the recently passed leap second.
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The fluffy stuff at the beginning is an introduction to the details.
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The next bit is a copy and paste from an email exchange with Jamie Zawinski and then some links saved at the bottom so they don't get lost before coming back around to it. The original intent of the article is to be about 3 times the current length.
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After being a degreed EE in industry for 26 years it gets pretty fucking boring reading a bunch of acronyme enhanced techno bable in run-on third person sententences with the drilled down lack of context of an autistic plastic pocket protector.
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Additionally the "normal" non-weird style lends itself to almost immediate obsolescence because of its lack of context.
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I'm not sure what you do with your days, but over here there's a mortgage, a kid with the flu, three projects that need attention for clients, past due taxes, and plenty of other "normal" duties vying for my time. If I spend time writing about time keeping in unix computing, I want it to be fun as well as informative.
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I didn't realize the arch community had such strict standards of boringness.
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I've been running this distro for 6 years, pretty much every day. I'm not a maintainer, but I am a reasonably knowledgable user. I'd like to spread some of that knowledge to help arch users understand how their whole system fits together. A comprehensive understanding is not reached by each specific detail alone, it requires context and inter-relation.
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The wiki should be THE ARCH BOOK. This requires that each article be maintained, not just a bunch of details that are correct in the moment but superfluous 6 months down the road. Otherwise it will always be in a shambles and mostly out of date with no cohesive vision that guides the reader or future contributions.
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That's my bit.
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Best of luck...
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==<s>New initscripts and hwclock daemon</s>==
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With the latest initscripts package, the hardware clock is kept updated differently than how it's explained here (for example it's not in rc.shutdown any longer), I am still trying to understand well, so I cannot update the article by myself. For now I'm marking it as out of date. -- [[User:Kynikos|Kynikos]] 16:09, 3 May 2011 (EDT)
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:At the moment I link the bug report that seems to be responsible for this change: {{Bug|13684}}. -- [[User:Kynikos|Kynikos]] 16:39, 3 May 2011 (EDT)
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::Understood and updated (also contributed by PeterL). -- [[User:Kynikos|Kynikos]] 06:17, 9 June 2011 (EDT)
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:::Updated references to setting system time from hardware clock as I noticed things have changed again in the latest initscripts [[User:PeterL|PeterL]] 20:20 17 Dec 2011 (GMT)
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==<s>Note in the About section</s>==
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Hi there. I just got throught installing arch on a dualboot system. I saw how I can configure all this time-stuff, but didn't get what it is I'm supposed to be doing. (No problem following instructions, but.. what's the current situation, and what's the target?) Found this page, and read it. I only understood clock and time. So I played around (with UTC, changing BIOS clock, windows clock, linux clock, rebooted and looked at how the other clocks reacted). Then it was ovious. Reading throught the about section again I was puzzled why I didn't understand the concept perfectly on the first read, because it's all there, in detail.
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So I added this note. I couldn't improve the About section itself, because it's all there already. But it's a lot of text with a lot of clocks (;) . I didn't want to dumb it down, and adding to it doesn't help the beginner, it's just more clocks. So I thought I'll just add a simple version of what's going on, seperate from the detailed information
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But I know it's dublicated information, so someone might just delete it for that reason, and this is why i write here. Please don't delete it. It's a little bit of a chicken and egg problem, at least for me. This article needs a very basic explanation of what going on.
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:Please sign your edits in talk pages.
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:Don't worry, it's going to stay, I've just reworded it a bit and removed the Note template since it can't be considered a note. -- [[User:Kynikos|Kynikos]] 07:08, 15 October 2011 (EDT)
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===<s>How to set Windows to use UTC</s>===
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Is there a reason we don't provide info on [https://wiki.archlinux.org/index.php/Rc.conf#Localization how to set Windows to use UTC] here? Can I just copy-paste the note? -- [[User:Karol|Karol]] 09:02, 28 November 2011 (EST)
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:You know that every time you write the word Win**** in the ArchWiki, god kills a kitten!
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:Yeah copy-paste it ;)
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:-- [[User:Kynikos|Kynikos]] 05:12, 29 November 2011 (EST)
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::I don't like cats, I prefer llamas. Windows Windows Windows Windows ;P
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::[https://wiki.archlinux.org/index.php?title=Time&diff=171563&oldid=170247 Note added]. Closing. -- [[User:Karol|Karol]] 07:00, 29 November 2011 (EST)
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==<s>hwclock daemon</s>==
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[[Time#hwclock daemon]] says that ''"[...] the {{ic|/etc/rc.d/hwclock}} daemon uses {{ic|hwclock}} to set the system and hardware clocks on boot [...]"'' but is that true? By looking at [http://projects.archlinux.org/initscripts.git/tree/hwclock hwclock's source code] it does nothing at boot. In fact that should be done by /etc/rc.sysinit as explained at the end of [[Time#Time standard]]. Probably somebody with good knowledge of the matter should come and clean things up.
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This discussion is also related to [[Talk:Network Time Protocol daemon#Syncing at boot]].
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-- [[User:Kynikos|Kynikos]] 11:03, 20 January 2012 (EST)
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: There is no need for good knowledge, source code of /etc/rc.d/hwclock and /etc/rc.sysinit are good enough (however both can be just edited by devs without notifying us :P). --[[User:AlexanderR|AlexanderR]] 19:19, 23 March 2012 (EDT)
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==<s>Hardware clock and system clock</s>==
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[[Time#Hardware clock and system clock]] says that setting the hwclock based on swclock uses the command "hwclock --systohc", but I tested by myself this command and seems that without the UTC parameter ("hwclock --systohc --utc") its sets the hwclock in localtime.
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This sounds a bit ambiguous because you can make an inference from what was said on above section ["To set the hardware clock directly (the argument must be in local time, even if you keep your hardware clock in UTC.)"] that the "hwclock --systohc" will do the same.
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(Get this info in section "Setting the hardware clock" on this link: [http://www.linuxsa.org.au/tips/time.html Linux Tips - Linux, Clock and Time])
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--[[User:Gbc921|Gabriel B. Casella]] 18:13, 11 March 2012 (EDT)
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:It is all your experimentations. It is probably better not to bother users THAT much by including following fragment form hwclock manpage into article:
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{{bc|
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    -u, --utc<br>
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    --localtime<br>
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            Indicates that the Hardware Clock is kept in Coordinated Univer‐
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            sal Time or local time, respectively.  It is your choice whether
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            to  keep  your  clock  in  UTC or local time, but nothing in the
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            clock tells which you've chosen.  So this option is how you give
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            that information to hwclock.<br>
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            If  you  specify the wrong one of these options (or specify nei‐
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            ther and take a wrong default), both setting and querying of the
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            Hardware Clock will be messed up.<br>
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            If  you  specify  neither  --utc nor --localtime, the default is
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            whichever was specified the last time hwclock was  used  to  set
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            the  clock  (i.e.  hwclock was successfully run with the --set,
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            --systohc, or --adjust options),  as  recorded  in  the  adjtime
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            file.  If  the  adjtime  file doesn't exist, the default is UTC
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            time.}}
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:It says "the default is whichever was specified the last time" but according to current {{Ic|/etc/rc.sysinit}} sources hwclock is always called early with either {{Ic|--utc}} or {{Ic|--localtime}} explicitly specified depending on user's {{Ic|HARDWARECLOCK}} value. Therefore most users are just not noticing all the mess. --[[User:AlexanderR|AlexanderR]] 19:19, 23 March 2012 (EDT)
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Revision as of 14:19, 21 August 2013

Using UTC in Windows can cause some problems

There's a fair amount of evidence to show that when you run Windows with UTC time, things get hairy:

* [1] See the Current Support Status In Windows section
* [2] Raymond Chen has a nice writeup

Most people shouldn't get touched by this, but I know plenty of times I've been bugged (namely, every single debugger reads the BIOS clock and attempts to not de-botch itself) when using Windows with UTC time. In my experience, Windows 8 also will force BIOS time into being Un-DST adjusted Localtime. Dangerous!

--Indrora (talk) 05:58, 31 October 2012 (UTC)