[pmwiki-devel] Internal server error message

[Peter Bowers]

On Thu, Oct 9, 2014 at 9:39 PM, StefCT <stefct4 at gmail.com> wrote:

> I think I have repeatedly used nested pagelists but haven't encountered
> any problems so far.
>
> ...
> Seems to work fine so far. Is there any downside to be expected from
> this solution?
>

Pagelists are a powerful feature, basically providing database-query-like
functionality on a flat-file based system.  Considering the immense task
that is inherent in database queries and the fact that there are no true
indices available, it is understandable that this process is relatively
complicated and processor & (sometimes) memory intensive.

Having messed around with the internals, my hat is off to those (PM, I
assume?) who came up with the idea and made it work.

Nesting pagelists understandably increases the processor & memory usage
geometrically.  So, yes, it works - I've used them and it sounds like
you're making good use of them.  But as the number of pages to process
increases it's going to use more memory, more processor, and take longer
and longer to load.  And your margin of error in the markup may get more
dicey and harder to debug when you nest the pagelists.

Ultimately if it's working for you, great - I wouldn't think it's a feature
to avoid.  But if you start running into 100% usage of your processor or
using up memory or extremely long load times for pages then this is
probably one of the first areas to look at.

-Peter
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.pmichaud.com/pipermail/pmwiki-devel/attachments/20141010/43420b46/attachment.html>