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<Quote>
<;)>that's why we have 64 bit processors</;)>
</Quote>
Still very much in infancy, but catching on [1].
Kind Regards,
Joe Chiusano
Booz | Allen | Hamilton
[1] http://www.nwfusion.com/news/2003/071464bit.html
Rick Marshall wrote:
>
> On Wed, 2003-08-20 at 09:08, Chiusano Joseph wrote:
> > <Quote1>
> > processor time to parse very large XML documents (say, 1,000 documents
> > of 1 terabyte each)
> > </Quote1>
> >
> > If one's XML documents are 1 terabyte large, then they better rethink
> > their system architecture and design, and chop their documents up into
> > smaller pieces. A 32-bit processor can itself address only up to 4GB of
> > memory.
>
> <;)>that's why we have 64 bit processors</;)>
>
> >
> > <Quote2>
> > maintenance issues driven by the smallest of interface changes or
> > presentation changes, that result in hundred of thousands if not
> > millions of manual static schema modifications, rippling across either
> > a very large number of smaller XML documents and their specific schemas
> > or through as many as a thousand or so documents
> > </Quote2>
> >
> > One should never have to perform "hundred of thousands if not millions
> > of manual static schema modifications" - an XML registry and/or a robust
> > content management system should enable updates to be made in one
> > central location and propagated to all of the pertinent places (which
> > reference the central location by pointers). This also addresses your #3
> > point.
> >
> > <Quote3>
> > transmission time across interchanges - whether lan, web or intranet
> > based, the time to transmit and parse result sets to XQuery are often
> > very large, and for very large XML documents this processing time is
> > unacceptably long.
> > </Quote3>
> >
> > A very valid and well-known issue - and one of the reasons that some
> > brainstorming over binary XML is going on these days.
> >
> > Kind Regards,
> > Joe Chiusano
> > Booz | Allen | Hamilton
> >
> > dbexcom wrote:
> > >
> > > I am concerned to hear this approach, and others here, discussed, without
> > > comment as to scaling issues regarding very large datastores (in XML
> > > documents or in relational dbms) that might be ten to several hundred
> > > terabytes in size.
> > >
> > > Specifically, in the following respects:
> > > 1- sheer size problems such as disk access time, out of memory conditions,
> > > and processor time to parse very large XML documents (say, 1,000 documents
> > > of 1 terabyte each) or a very large number of XML documents of smaller size
> > > (say, 5,000,000 5MB docs).
> > > 2- maintenance issues driven by the smallest of interface changes or
> > > presentation changes, that result in hundred of thousands if not millions
> > > of manual static schema modifications, rippling across either a very large
> > > number of smaller XML documents and their specific schemas or through as
> > > many as a thousand or so documents of 1 terabyte each in size. Even if such
> > > ripple effect maintenance can be automated, the processing time required to
> > > update, say, 5,000,000 XML doc files of 5MB each cannot be said to be real
> > > time, so perhaps weeks of processing time is required before the interface
> > > mods can be subject to just one full test.
> > > 3- consistency across versions, releases, XML standards and tool sets (MS,
> > > SQL Server, MySQL, Oracle, etc) considering that a very large scale project
> > > will take some time to mature (possibly years), and that a lack of backward
> > > compatibility could drive massive changes into the basic XML design
> > > structure and overall document architecture.
> > > 4- transmission time across interchanges - whether lan, web or intranet
> > > based, the time to transmit and parse result sets to XQuery are often very
> > > large, and for very large XML documents this processing time is
> > > unacceptably long. People want results in five to eleven seconds, not
> > > minutes, not hours.
> > >
> > > I have specific experience in very large paper based, and relational
> > > database systems. From time to time, I see folks scale up systems that work
> > > fine, up to a point, past which they are forced to redesign from scratch.
> > >
> > > While I agree that broadly generalized discussions are the most common form
> > > of technical exchange of information, having seen several of these pilot
> > > efforts crash and burn, I feel a moral obligation to suggest that some
> > > comment be made as to scaling issues, known propagation or ripple effects,
> > > and sheer size problems that come into play when viable "average"
> > > architectures are scaled beyond their design parameters.
> > >
> > > In reference to this specific method, I submit that when dealing with a
> > > very large repository of prose, that a very large number of "profile
> > > documents" is possible, and that the number of possible "profile documents"
> > > correlates to some index of the context and the subject matter and the
> > > usage purposes (inquiry / result pairs), a result that to my mind increases
> > > or scales up as the number of prose entities scales up. I will go further
> > > and say that, for instance, for all articles ever published in the
> > > scientific journal "Nature", or perhaps all items in the U.S. Library of
> > > Congress or all pending applications and issued patent files in the U.S.
> > > Patent Office, this number of possible "profile documents" becomes very
> > > large indeed. Though it may be possible to satisfy as much as a majority if
> > > inquiries with a small number of such structures, the rest of the
> > > inquiries, it seems to me, will require an ever increasing number of
> > > "profile documents" to satisfy so that satisfying the last 1 percent of
> > > such inquiries might require several thousands of such "profile documents",
> > > if not tens of thousands or hundreds of thousands.
> > >
> > > So, I am interested to hear about practical applications using XML only
> > > implementation (XQuery, XML, XSLT, XPath, etc) that deal with wide ranging
> > > subject matter, such as is found in the scientific journal "Nature", or
> > > perhaps all items in the U.S. Library of Congress or all pending
> > > applications and issued patent files in the U.S. Patent Office, to a very
> > > broad audience, across scientific disciplines and cultures (and possibly
> > > languages), for a very large data repository of mixed content (prose,
> > > graphics, slides, photos, video, sound, other streaming data sources or
> > > media) measured in tens or hundreds of terabytes.
> > >
> > > While XML is superb at document mark up, in my experience almost as good as
> > > TeX, it does not strike me as the best tool for the job when dealing with
> > > very large scale data repositories. Still, I have an open mind and perhaps
> > > someone here can enlighten me.
> > >
> > > Thank you.
> > >
> > > At 10:28 PM 8/18/2003 -0400, you wrote:
> > > >One of the difficulties in considering factoring out functionally
> > > >dependent entities from prose, is that the block of prose may itself not
> > > >be worth reusing. That is, the prose may be a one-shot document whose
> > > >original intent is simply to present information, not to act as a reliable
> > > >container for access by clients with a variety of intents.
> > > >One thing I've done is to try to identify those concepts which are best
> > > >understood, are most firmly established, and which serve as the focus of
> > > >the stakeholders' activities and communications. Then design a profile
> > > >document for each of these high-level concepts, which provide context for
> > > >making pointers and for generating identifiers. The profiles are designed
> > > >to provide some elements which are rigidly structured, and other elements
> > > >which are prose with mixed content. In one case at least, this allowed me
> > > >(with a stylesheet) to resolve most cross references internal to the
> > > >document itself, minimizing calls to scan external documents. Also,
> > > >depending upon the nature of your data and your validation techniques, you
> > > >may be able to use the mixed content prose as the source of the definitive
> > > >information, rather than just as glue.
> > > >It is certainly something a good CMS can help with, but I've also used
> > > >DSSSL and XSLT/XPath for doing just this sort of thing with reasonable
> > > >results. You might also want to check out DITA by Michael Priestley et al.
> > > >of IBM, which I think intends to facilitate topical reuse.
> > > >
> > > >Roger L. Costello wrote:
> > > >
> > > >>Hi Folks,
> > > >>I am working with some people who wish to migrate from an
> > > >>all-prose format to a prose-plus-reusable-XML-fragments
> > > >>format.
> > > >>They have some data in prose that is useable in many contexts. They
> > > >>want to break out that reusable data into XML fragments. However,
> > > >>they want to continue to provide the prose style.
> > > >>For example, consider this prose data:
> > > >><para>The city of Miami, Florida (pop. 1, 234,000) is a sprawling city
> > > >>with many attractions. Miami Beach is a popular attraction. The
> > > >>spring tide is ... The neap tide is ... </para>
> > > >>Examining this prose we can extract reusable info about the city of
> > > >>Miami:
> > > >><City id="Miami">
> > > >> <state>Florida</state>
> > > >> <population>1,234,000</population>
> > > >></City>
> > > >>We can also extract reusable info about tide data on Miami Beach:
> > > >><TideData id="MiamiBeachTides">
> > > >> <springTide>...</springTide>
> > > >> <neapTide>...</neapTide>
> > > >></TideData>
> > > >>The problem now is to create a framework which allows the prose
> > > >>to bring-together the independent, reusable XML components.
> > > >>Conceptually, what is desired is a "glue framework" like this:
> > > >><para>The <ref href="Miami.xml"> is a sprawling city with
> > > >>many attractions. Miami Beach is a popular attraction. The
> > > >>tides are <ref href="MiamiBeachTides.xml"><para>
> > > >>Thus, the prose is "glueing" together the XML fragments.
> > > >>Is this a problem that you have experience with? What "glue
> > > >>framework" have you used? What strategy did you use to merge
> > > >>the XML fragments with the prose? Is there is a standard way
> > > >>of combining semi-structured data with structured data?
> > > >>/Roger
> > > >>
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