[Uml-devel] Building umlwidgets from textitems

[Ralf Habacker]

Gopala Krishna schrieb:
> On Wed, Jun 25, 2008 at 7:29 PM, Ralf Habacker <ralf.habacker at freenet.de> wrote:
>
>   
>>> The performance is quite good !
>>>
>>> My only concern is probable increase in memory usage,
>>> But i think this is manageable as the number of widgets on a diagram
>>> is usually < 50.
>>>
>>>       
>> Any idea how much more memory will be used ? That would help to estimate the
>> limits.
>>     
>
> Hmm. That dragged me to do some profiling, which i rarely do :-)
> I modified my textitem program a bit to study and initially used
> krunner's "system activity monitor" to note memory usage.
> The following is the program's snapshot showing 100 class diagram like
> items which have 4 text items each. (i doubt there will ever be so
> many diagrams anyway ;) )
>
> http://tinyurl.com/4mqtlm
>
> Here is snapshot of ods file i used for analysis(googledocs seems to
> be too much, so i decided to post picture instead)
>
> http://tinyurl.com/4ohe7q
>
>
> Then i realized there is a tool called massif from valgrind and i
> tried it for the first time. Here is the graph of memory snapshots
> taken.
>
> http://tinyurl.com/48hg4b
>
>
> I don't know how to extract or visualize lot more info produced by
> massif. I would be glad if any of you can step in to investigate it
> more :-)
>
> Here are the links to massif's output
>
> http://krishna.ggk.googlepages.com/out.txt
> http://krishna.ggk.googlepages.com/massif.out.6191
>
>
> My Conclusions:
>
> Currently i found the performance to be very good even with 400 + 100
> items with hover, tootip effects.
> Infact i ran the program without any optimization features enabled
> from qt4.4's graphicsview and memory usage also isn't bad.
> The test program used 7516K at most(with 100 + 400 items) and even if
> this is considered "Extra" it isn't too much :)
>   
with the assumption that  the Hoster objects take about the same memory 
as the textItem objects - the oo calc sheet shows that each object takes 
about 10KB, which looks good.
>
> So please give me your valuable opinion, whether to continue with text
> items or not ?
>   
I'm not the umbrello maintainer - but for my opinion is is good to have a wrapper class in this area to be able to extend/change the display/handling of text items in a central place, so this approach should be continued. 

Ralf