[Opensim-dev] Timezones, UTC, GMT & PST

[Gerhard Dünnebeil]

When dealing with time you have to distinguish between the time the 
machines work on and the time the users sees.

Introducing time zones at the wrong level also introduces a lot of 
confusion as you (the developer) always have to know with which time 
zone you currently deal.

MySQL isn't really an issue as you can set the time zone you want to 
work in with the session.

So my thoughts:
Use UTC internally; that includes storage of data, machine to machine 
communication, ....
Use the users time zone when (and only when) communicating with the 
user, which is mainly when times are displayed.

This is easier as one might think, as using UTC as the time base is 
available in all standard OS (windows, linux, ...) these days. There is 
no need to set a system clock to UTC as long as the system knows the 
offset to UTC.

Gerhard


Dahlia Trimble wrote:
> With the err... um... inevitable future event when the LL grid opens 
> the doors to full interoperability, and given that their large 
> customer base is accustomed to using "SLT" (California time) and all 
> the scripts that may assume SLT, shouldn't we weigh that option over 
> UTC or GMT or CUT or whatever it's called these days?
>
> On a side note, regions running in virtual machines may have less 
> control over the system clocks than regions running in a regular 
> machine. I'd like to suggest that region times could be configured in 
> OpenSim.ini and/or set by a central server using ntp or a similar 
> protocol.
>
> On Sun, Jan 18, 2009 at 10:32 AM, Charles Krinke <cfk at pacbell.net 
> <mailto:cfk at pacbell.net>> wrote:
>
>     There are some issues coming up about timezones and grids. It
>     seems that events, scripts, web interfaces and other things are
>     affected by timezones. It gets a bit more complicated when one
>     considers that our mysql logic uses local time with calls that
>     involve NOW().
>
>     Some folks feel that all the time on all the sims on all the grids
>     should be set to UTC, and that is a reasonable approach.
>
>     Others feel that a UGAIM should set the timezone for a grid and
>     tell the sims connected to that UGAIM what timezone they are in
>     and what time it is at the time of grid registration with a UGAIM,
>     and that is also a reasonable approach.
>
>     There is more. But, rather then just declaring what I might feel
>     to be the answer, I would like to seek a consensus that is best
>     for OpenSim and any comments or suggestions are greatly
>     appreciated to this "timely" subject.
>
>     Charles
>
>     _______________________________________________
>     Opensim-dev mailing list
>     Opensim-dev at lists.berlios.de <mailto:Opensim-dev at lists.berlios.de>
>     https://lists.berlios.de/mailman/listinfo/opensim-dev
>
>
> ------------------------------------------------------------------------
>
> _______________________________________________
> Opensim-dev mailing list
> Opensim-dev at lists.berlios.de
> https://lists.berlios.de/mailman/listinfo/opensim-dev
>