[vwnc] Threaded XML-unmarshalling?

> Hello,
>
> I wonder whether it is possible to run a time-expensive xml-unmarshalling  
> task in a concurrent vw thread in order to keep the UI responsive. I am  
> thinking of something like:
> p := [|doc|
> doc := (XMLParser new)
> on: xmlfile;
> scanDocument.
> manager unmarshall: doc] promise
> However, since neither the XMLParser nor the XMLObjectMarshalingManager  
> seems to yield the process they're running in, it does not work. Is there  
> a way I am not aware of or some "safe code modification" to get the  
> desired result?
>
> Regards, Steffen
> _______________________________________________
> vwnc mailing list
> [hidden email]
> http://lists.cs.uiuc.edu/mailman/listinfo/vwnc
>  

> Hi Holger,
>
> I am not sure to 100%, but I think it won't work. Once the
> unmarshalling process runs, it never lets yields the processer to
> other threads, thus the effect would be the same as computing the
> value directly when it's needed. But I inteded to unmarshall in
> background, while the user takes other actions, to save time.
> Please correct me, if I am wrong!
>
> Cheers,
> Steffen
>
> Am 14.07.2009, 13:21 Uhr, schrieb Holger Guhl <[hidden email]>:
>
>> Hi Steffen,
>> could it be an option to use the #promiseAt: method instead of
>> #promise ? If the XML unmarshaling process runs at priority less than
>> the UI process you have the desired effect...
>>
>> Cheers,
>> Holger
>>
>> Steffen Märcker schrieb:
>>> Hello,
>>>
>>> I wonder whether it is possible to run a time-expensive
>>> xml-unmarshalling  task in a concurrent vw thread in order to keep
>>> the UI responsive. I am  thinking of something like:
>>> p := [|doc|
>>>     doc := (XMLParser new)
>>>         on: xmlfile;
>>>         scanDocument.
>>>     manager unmarshall: doc] promise
>>> However, since neither the XMLParser nor the
>>> XMLObjectMarshalingManager  seems to yield the process they're
>>> running in, it does not work. Is there  a way I am not aware of or
>>> some "safe code modification" to get the  desired result?
>>>
>>> Regards, Steffen
>>> _______________________________________________
>>> vwnc mailing list
>>> [hidden email]
>>> http://lists.cs.uiuc.edu/mailman/listinfo/vwnc

> Steffen,
> I have just tried this:
>     [CAST.XMLObjectReader importUAXFileset] promiseAt: Processor  
> userBackgroundPriority
>
> It's code from of my recent projects, implemented wit VisualWorks 7.6.
> The job is still running while I am writing this and tries to parse  
> files with XML data (total of about 25 MB, 73.000 objects, significantly  
> more XML nodes) and convert (unmarshal) them into Smalltalk objects of  
> the project domain. The entire VisualWorks image with all tools remains  
> highly responsive, I can use menus to open Browsers which pop up  
> immediately without flicker or noticeable delay, and believe me my  
> computer is a quite aged and slow. Opening the ProcessMonitor I can  
> watch the busy process working hard.
> Now it has finished and the promise has the result.
> Since user processes (GUIs) are supposed to run at  
> #userSchedulingPriority it should work for the general scenario you are  
> describing. It's worth giving it a try.
>
> Cheers
>
> Holger Guhl