Cart
[Home] [By Thread] [By Date] [Recent Entries]
This is in fact exactly the kind of thing that I am thinking, with at least a couple other optimizations thrown in to make processing in-place in Java fast. sdw "Samuel R. Blackburn" wrote: > You know, if you parse the XML into a carefully designed data structure, > you could write that structure to a file. To re-read the data, you would > simply memory map the file (or put the structure into a shared memory > segment). If the structure is designed so offsets are used instead of > pointers, you could navigate is quickly and not have to worry about > memory addresses involved. The OS will only page in those portions > of the file that are really used. > > Just a thought, > > Sam > > -----Original Message----- > From: Stephen D. Williams <sdw@l...> > To: xml-dev@i... <xml-dev@i...> > Date: Thursday, March 25, 1999 10:08 PM > Subject: Re: Is there anyone working on a binary version of XML? > > >"Simon St.Laurent" wrote: > > > >> At 03:36 PM 3/25/99 -0500, DuCharme, Robert wrote: > >> >>I know, I know, this is anathema to what many of you feel is the > >> >>essence of XML, and I agree to a point. > >> > > >> >It's not so much about feelings, as about contradicting the XML spec. > >> > > >> >[...] > >> > > >> >Applying XML concepts to a binary data format sounds interesting and > >> >potentially useful, but it wouldn't be XML. > >> > >> One of these days I'd really love to stop talking about what is and isn't > >> XML, though I know it's fun, and start talking about what we can do with > >> XML and XML-like structures, whether they are SAX event flows, DOM trees, > >> or binary formats that build on an XML foundation. > >> > >> We might even get some real work done - and it might even be fun. > > > >I agree with the sentiment Simon. > > > >I'm required (or am requiring myself) to get a lot of real work done very > >quickly in the next > >6 months hence my focus... > > > >Semantically, I am talking about using XML. After parsing and creating a > >DOM tree or SAX > >events, you no longer have XML but a data structure semantically equivalent > >to an XML > >document. Another way to think about what I'm proposing is that it is a > >cache of the data > >structures produced from processing an XML document, cast in a openly > >documented data > >structure that is already flattened and ready for IO. > > > >In fact, this is how I arrived at this design after following a few other > >design constraints > >and observations. Of course from there it is a short stop to say that you > >can throw away the > >'external' XML representation if you can recreate it from XMLb. > > > >My scheme makes parsing of XML a non-issue. If I only have that advantage > >within my closed > >system, so be it, converting to and from XML for external purposes is in > >fact what I intend to > >do. > > > >In my case, I'm architecting a high speed clustering system, primarily > >targeted at Linux/Unix > >and Java. In this kind of system of course you are splitting applications > >into many servers. > >Of course the communication between those nodes is really internal > >application communication, > >the equivalent of that DOM tree, so it makes sense to optimize it. Think > of > >it this way, > >you'd seldom design a large app where every method needs to parse the XML > >text block passed to > >it to get a DOM tree (or SAX events) if the calling method has a DOM tree > >that it could just > >pass. > > > >sdw > > > >> Simon St.Laurent > >> XML: A Primer > >> Sharing Bandwidth / Cookies > >> http://www.simonstl.com > > > > > >-- > >OptimaLogic - Finding Optimal Solutions > >Web/Crypto/OO/Unix/Comm/Video/DBMS > >sdw@l... Stephen D. Williams Senior Consultant/Architect > >http://sdw.st > >43392 Wayside Cir,Ashburn,VA 20147-4622 703-724-0118W 703-995-0407Fax > >5Jan1999 > > > >xml-dev: A list for W3C XML Developers. To post, mailto:xml-dev@i... > >Archived as: http://www.lists.ic.ac.uk/hypermail/xml-dev/ and on > CD-ROM/ISBN 981-02-3594-1 > >To (un)subscribe, mailto:majordomo@i... the following message; > >(un)subscribe xml-dev > >To subscribe to the digests, mailto:majordomo@i... the following > message; > >subscribe xml-dev-digest > >List coordinator, Henry Rzepa (mailto:rzepa@i...) > > xml-dev: A list for W3C XML Developers. To post, mailto:xml-dev@i... Archived as: http://www.lists.ic.ac.uk/hypermail/xml-dev/ and on CD-ROM/ISBN 981-02-3594-1 To (un)subscribe, mailto:majordomo@i... the following message; (un)subscribe xml-dev To subscribe to the digests, mailto:majordomo@i... the following message; subscribe xml-dev-digest List coordinator, Henry Rzepa (mailto:rzepa@i...)
|
