Re: daylight saving makes computer wake up late

["Morten Friesgaard" <friesgaard@gmail.com>]

Hi again.
when I installed Gentoo i copied the timezone with

# cp /usr/share/zoneinfo/Europe/Copenhagen /etc/localtime

last week i did a diff on the files, and the differed, so I changed it
to a symbolic link
# ln -sf /usr/share/zoneinfo/Europe/Copenhagen /etc/localtime

well I still got the same problem...

Don't see any way to solve it but my temporary script...
/Morten

On 14/04/07, Dominique Michel <dominique.michel@citycable.ch> wrote:
> Le Sat, 14 Apr 2007 12:06:49 +0200,
> "Morten Friesgaard" <friesgaard@gmail.com> a écrit :
>
> > Hi again.
> >
> > I have the following settings:
> > CLOCK="UTC"
> > TIMEZONE="Europe/Copenhagen"
> > CLOCK_SYSTOHC="yes"
> >
> On gentoo, I also have to copy one file as /etc/localtime. It the file
> in /usr/zoneinfo that correspond to your local time. Don't copy the files
> in /usr/zoneinfo/Etc, but the one that correspond to your geographical
> location, as example /usr/zoneinfo/Europe/London and rename it
> to /etc/localtime.
>
> But those settings can differ between different distributions. If it still
> doesn't work, take a look in the doc or in a forum for your distribution. Some
> bios also have a setting for this.
>
> Dominique
>
> > but still nothing works correctly, so until it is fixed, i going to
> > use the following script (now it works)
> >
> > hope anyone else can benefit from it :)
> > /Morten
> >
> > ------------------------------------------------------------------------
> > #script /usr/sbin/mythsettime
> > #sudo chmod u+x /usr/sbin/mythsettime
> >
> > d=$1
> > t=$2
> >
> > #AT=`cat /proc/acpi/alarm`
> > RT=`date -d "${d} ${t} 2 hours ago" +'%Y-%m-%d %H:%M:%S'`
> >
> > echo $RT > /home/mythtv/myth.time
> > echo $RT > /proc/acpi/alarm
> > #echo $AT
> > ------------------------------------------------------------------------
> >
> >
> > On 08/04/07, Dominique Michel <dominique.michel@citycable.ch> wrote:
> > > Le Sun, 8 Apr 2007 20:18:28 +0200,
> > > "Morten Friesgaard" <friesgaard@gmail.com> a écrit :
> > >
> > > > I'm not sure what to do, how do I make these changes?
> > > >
> > > > when I run the following it gives me somewhat the same values, but it
> > > > seems the BIOS clock i different (?!)
> > > > # hwclock ; date
> > > > Sun Apr  8 20:13:56 2007  -0.069330 seconds
> > > > Sun Apr  8 20:13:55 CEST 2007
> > > >
> > > > it worked before daylight savings, is it something I can ignore and
> > > > still get it to wake up the corret time?
> > > >
> > > > should I change
> > > > TIMEZONE="Europe/Copenhagen"
> > > >
> > > > to
> > > > TIMEZONE="UTC"
> > > > ??
> > > >
> > > > /Morten
> > > >
> > >
> > > You must have 2 things:
> > >
> > > CLOCK="UTC"
> > > TIMEZONE="Europe/Copenhagen"
> > >
> > > The first one tell the OS that the rtc use UTC time, the second one at it
> > > must convert the UTC time into Europe/Copenhagen time to get the current
> > > system time.
> > >
> > > On gentoo I also have an option that set the Hardware Clock to the current
> > > System Time during shutdown:
> > >
> > > CLOCK_SYSTOHC="yes"
> > >
> > > Some linux distributions use CLOCK="local" because, I guess, they are
> > > thinking at it is best to do so when you are double booting with windows.
> > > It is wrong because when the rtc use local time, the system have to change
> > > the time in the rtc (read in the hardware) when the daylight is changing,
> > > and each OS will change the time in the rtc.
> > >
> > > So, you will get the correct time after booting the first OS, a shift of one
> > > hour after booting the second OS, and so on. It is much simpler to use UTC
> > > with all the OS in the box, and that even with window$ (it is an option in
> > > the register base, I don't remember where but a google search will give you
> > > the reference.)
> > >
> > > With CLOCK="UTC", the time in the rtc (in the hardware) will never change,
> > > the OS will just interpret it with the value of TIMEZONE.
> > >
> > > Ciao,
> > > Dominique
> > >
> > > >
> > > > On 08/04/07, Henrique de Moraes Holschuh <hmh@hmh.eng.br> wrote:
> > > > > On Sun, 08 Apr 2007, Morten Friesgaard wrote:
> > > > > > I'm running a mythbox, and ever since we had our yearly change of
> > > > > > daylight savings (summer time) my computer wakes up late. At first it
> > > > > > was only an hour, then I set the time with hwclock (realised that
> > > > > > CLOCK_SYSTOHC="no"), now it is 2 hours late. And it is really precise
> > > > > > (1-2 hours later), and it is certainly because of daylight savings.
> > > > > >
> > > > > > Any ideas?
> > > > >
> > > > > My guess is that you have to set ACPI wake times to *exactly* the time
> > > > > zone you use your RTC in.  Typically UTC, but semi-broken MS-compatible
> > > > > setups use the local time zone.
> > > > >
> > > > > The kernel can know the timezone, but almost nobody ever sets that
> > > > > right, and it is not summer-time aware anyway (too complex).  It is
> > > > > best to just keep everything UTC as far as the kernel goes, *including*
> > > > > the RTC.
> > > > >
> > > > > --
> > > > >   "One disk to rule them all, One disk to find them. One disk to bring
> > > > >   them all and in the darkness grind them. In the Land of Redmond
> > > > >   where the shadows lie." -- The Silicon Valley Tarot
> > > > >   Henrique Holschuh
> > > > >
> > > > -
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> > >
> > >
> > > --
> > > Dominique Michel
> > >
> > > --
> > > N.B.: Tous les emails que je reçois sont filtrés par spamassassin avant de
> > > me parvenir.
> > >
> > -
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>
>
> --
> Dominique Michel
>
> --
> N.B.: Tous les emails que je reçois sont filtrés par spamassassin avant de me
> parvenir.
>
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