[Tikiwiki-devel] Comments library (was: Comment on a single, underlying text representation model)

[David R. N. <d.r...@qu...>]

Bryan Pfaffenberger (is that the famous author of computing books 
that non-computer users can read?) wrote:
> Aren't there some performance penalties here? My users have posted tons of
> stuff to their forums, and performance has really degraded... new topic
> forum posts go into the same database table as forum comments and other
> types of comments. I had my students post their papers to forums, with
> disastrous results -- tiki-view_forum's performance soon degrades to the
> point that it is barely usable.

I don't think it matters which table the data goes into here,
but the efficiency in which data is extracted when displaying
threads of comments.

When I was doing some performance timings earlier this year, I
found that after tikilib, it was the comments library that took
the most time. So that probably should be the next target for
optimization.

In the comments library (and in the forum comments handling,
which is slightly different), there are plenty of examples
of code which use loops in PHP to extract values a few at
a time from the database, rather than writing an SQL query
that extracts the complete table of results in one call.
Correct me if I am wrong, but I don't think there is a
single SQL query that uses a join anywhere in Tikiwiki.

Since MySQL is fast at doing joins, while communication between
PHP and MySQL is relatively slow, it is worth getting someone
skilled at SQL (as opposed to skilled at PHP) to go through the
slower parts of the code, such as the commenting. I would do it
if I wasn't just going to spend several weeks doing nothing but
mark examination papers.

I don't think that the underlying text representation model
would make much difference in performance here, although
the maintenance would be eased if the commenting links
were handled the same way everywhere throughout Tikiwiki.

-- 
Dr. David R. Newman, Queen's University Belfast, School of
Management and Economics, Belfast BT7 1NN, Northern Ireland (UK)
Tel. (direct) +44 (0)28 9027 3643 (office) +44 (0)28 9033 5011
FAX: +44 (0)28 9033 5156  mailto:d.r...@qu...
http://www.qub.ac.uk/mgt/staff/dave/