[fpc-pascal] How to save a huge XML?

[Sven Barth]

On 18.06.2013 19:18, Michael Van Canneyt wrote:
>
>
> On Tue, 18 Jun 2013, Sven Barth wrote:
>
>> On 18.06.2013 16:01, Michael Van Canneyt wrote:
>>>
>>>
>>> On Tue, 18 Jun 2013, Marcos Douglas wrote:
>>>
>>>> On Tue, Jun 18, 2013 at 10:44 AM, Michael Van Canneyt
>>>> <michael at freepascal.org> wrote:
>>>>>
>>>>>
>>>>> On Tue, 18 Jun 2013, Marcos Douglas wrote:
>>>>>
>>>>>>> No. The writer already uses a fixed buffer. Your problem is the
>>>>>>> use of
>>>>>>> TXMLDocument.
>>>>>>
>>>>>>
>>>>>> Ideas? Maybe do what Antonio Fortuny said before?
>>>>>>
>>>>>>>
>>>>>>> Simply put: logging to XML (worse: using DOM) is a VERY bad idea.
>>>>>>
>>>>>>
>>>>>> Well, this is a request of my client. Other process will read this
>>>>>> XML.
>>>>>
>>>>>
>>>>> Under no circumstances should you use TXMLDocument for this.
>>>>
>>>> So, where is recommended to use TXMLDocument class?
>>>
>>> General XML processing. Small documents.
>>>
>>> You should be aware that the DOM always has the whole XML document in
>>> memory, plus a substantial amount of overhead. This is not something FPC
>>> specific, but is inherent in the DOM model. (a W3 spec)
>>>
>>> Regardles of XML or not: keeping logs in memory is simply a bad idea.
>>> You can buffer them for performance reasons, but after some time you
>>> must write to file.
>>>
>>> The DOM model does not allow this.
>>
>> Maybe we should implement a simple API for just writing an XML to a
>> stream. Something like SAX only the other way round. E.g.
>
> It exists for HTML already. So: yes, not a bad idea.

Hmm... if we have something for HTML already it should be rather easy to 
adapt, right? Or we could at least pull the common parts out...

Regards,
Sven