fast deep-copying of instances

[Michal Vitecek]

Robert Brewer wrote:
>Michal Vitecek wrote:
>>  hello,
>> 
>>  i have a data cache which sits between a slow database and 
>> my server and
>>  it's used to cache data retrieved from the database. in 
>> order for it to
>>  work correctly (race-conditions) i need a fast deep-copying of
>>  instances (the cache is used heavily).
>> 
>>  i tried to use copy module but it's *very* slow, then i tried cPickle
>>  to pickle and depickle instances which was faster, but still slow.
>>  
>>  then i've come across cCopy which is 8x faster than copy, but
>>  unfortunately it doesn't work with new style classes because type()'s
>>  return is crappy for them. so the question is: does there 
>> exist a fast
>>  copy module which works with new style classes?
>
>If you don't find something pre-built, you can always build it yourself
>into the classes which you are caching, via __copy__ and __deepcopy__
>methods.:

 i know of this mechanism but
    a) i fear it would be still slower than cPickle and be quite time
       consuming to implement (lots of classes)
    b) cCopy is the C implementation of the copy module so it's
       "lightning" fast

 
 the current cCopy is at http://www.jessikat.fsnet.co.uk/cCopy.html . if
 someone would be so kind to add support for new style classes to it (or
 tell me how to do it), i'd be very very grateful.

        thank you,
-- 
		fuf		(fuf at mageo.cz)