[Twisted-web] [Nevow] template performance

Fri Dec 15 06:33:55 CST 2006

Tristan Seligmann ha scritto:
> * Manlio Perillo <manlio_perillo at libero.it> [2006-12-15 11:56:55 +0100]:
> 
>> First let me say that I really like Nevow template system.
>> Once you became expert with it, it proves to be really flexible.
>>
>> The problem is the performance.
>> I have done a simple test with the rendering of a table 5 * 20, Nevow 
>> against Django, and Nevow is much slower.
>>
>> The problem is that, I think, there are a lot of objects adaptation.
> 
> Can you be more specific about this? What objects are being adapted, and
> why do you think this is the cause of slowness?
> 

I'm not sure on what's the problem.

However if I render this template (without data):

<!DOCTYPE html
   PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
   "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

<html xmlns="http://www.w3.org/1999/xhtml"
       xmlns:n="http://nevow.com/ns/nevow/0.1"
       lang="en" xml:lang="en">
   <head>
     <title>Test performance</title>
   </head>
   <body>
     <p>Some test</p>
   </body>
</html>

I got ( 100000 * t.timeit(number=10000) / 10000) )

manlio at synapsis:~/projects/tests/nevow$ python static2.py
9.85 usec/pass

manlio at synapsis:~/projects/tests/django$ python static2.py
13.31 usec/pass

Nevow for every data object calls inevow.IContainer.child.
The problem can be here, since it is called 25 times (the number of rows 
in the table)

Regards  Manlio Perillo