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> At 10:16 AM 4/19/2005, you wrote:
> > > Quincey Koziol <koziol@xxxxxxxxxxxxx> writes:
> > >
> > > > I was planning on including a hidden field to disambiguate
> > objects that
> > > > were created at the same time, so this wouldn't happen. Since there's
> > > > no
> > > > advantage to using a creation order field instead of using the
> > creation time
> > > > when determining the n'th object inserted into a group (when
> > factoring deleted
> > > > objects into the equation), I'm still leaning toward using a time
> > instead of an
> > > > index for this purpose. Using the time provides the same
> > functionality and
> > > > adds information as well.
> > > >
> > > > I'm still somewhat split on the issue however and would welcome
> > persuasive
> > > > arguments in favor of one mechanism or the other. :-) I'm also
> > thinking about
> > > > including both fields (creation order and creation time) and allowing
> > users to
> > > > create an index on either, to suit their particular needs...
> > >
> > > Quincey,
> > >
> > > What happens is a machine with an inaccurate time adds a variable to a
> > > dataset?
> >
> > It'll get the "wrong" creation time and inserted in the index
> >appropriately, as you'd expect. I don't think this is a major problem
> >though,
> >because I don't think that most files will get edited on multiple machines in
> >a very short timeframe.
>
> This will happen in parallel computing systems. Even cluster nodes can be
> off from each other a few seconds. And then the Grid computing will
> make it even worse as machines will be in different time zones and bigger
> time latency.
Actually, I don't think it'll be a problem in parallel systems, because only
one processor will be writing the metadata to the file and the metadata will
reflect that machine's time settings.
Quincey
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