Re: [cgiapp] Dynamic charts?

[Cees Hek <suppressed>]

On 4/27/05, Jason Purdy <suppressed> wrote:
> Mark A. Fuller wrote:
> That's interesting.  The underlying data is changing a lot right now,
> but in the future, that'll slow down.  So I could tuck a max(id) in the
> Storable file and do a quick query to see if that's less than the
> current max(id) of the db.  If so, then do the re-gen.
> 
> Thanks, Mark!  I'm also interested in more feedback and ideas.

You need to figure out what your usage scenarios are going to be.

How expensive is it to generate all combinations of your dataset?  Are
there just a few graphs, or do you have thousands of possibilities? 
How often does the data change?  Do the users look at all the data all
of the time, or do they only look at some of the data most of the
time?  Is it OK to show old data for a short period of time.

If you can easily pregenerate all your data, and only have to
regenerate your data every 30 minutes or so, then that would be the
best way to go.  Your clients download static content, which means you
can easily manage your load even during peak times.  Pregeneration
could also be triggered automatically whenever a change occurs.

If your dataset is really large, and much of the data will never be
looked at, then pregenerating all the data every 30 minutes will be
very wasteful (and may not be possible at all).  In that case you are
better off doing a dynamic system, possibly with some caching.  But in
this case controlling the load of your site will be more difficult,
because it will not scale nearly as well as the pregeneration method.

You have to find a good balance between the two methods.

Cheers,

Cees

---------------------------------------------------------------------
Web Archive:  http://www.mail-archive.com/suppressed/
              http://marc.theaimsgroup.com/?l=cgiapp&r=1&w=2
To unsubscribe, e-mail: suppressed
For additional commands, e-mail: suppressed