Enhancing parsing performance 2003-01-13 - By Brian Madigan
Turn validation off!
DOMParser parser = new DOMParser( );
parser.setFeature
("http://xml.org/sax/features/validation",
false);
or something to that effect. If I am not mistaken,
that should stop any dtd validation from happening.
--- Jean Georges PERRIN <jgp@(protected)> wrote:
> Hi,
>
> Thanks for the hope message!
>
> I was timing the whole method, I focused on parser
> creation and parse time
> now.
>
> I changed my code to:
> public void load () {
> DOMParser parser;
> Logger log =
>
ThinStructureConfiguration.getInstance().getLogger();
>
> try {
> long start = System.currentTimeMillis();
> parser = new DOMParser();
> long stop = System.currentTimeMillis();
> log.finest ("Creating parser took " + (stop -
> start) + " ms");
> }
> catch (Exception e) {
> log.severe ("Error: Unable to instantiate
> parser");
> return;
> }
>
> try {
> long start = System.currentTimeMillis();
> parser.parse(m_file.toURI().toString());
> long stop = System.currentTimeMillis();
> log.finest ("Parsing of " + m_file.getName() +
> " took " + (stop -
> start) + " ms");
> m_document = parser.getDocument();
> }
> catch (SAXParseException e) {
> // ignore
> }
> catch (Exception e) {
> String msg;
> msg = ("Error: Parse error occurred, " +
> e.getMessage());
> if (e instanceof SAXException) {
> e = ((SAXException)e).getException();
> }
> msg += '\n' + e.toString();
> log.severe (msg);
> }
> }
>
> Results are:
> Jan 13, 2003 11:52:20 PM
> com.awoma.ts.ui.impl.XHTML11Window load
> FINEST: Creating parser took 251 ms
> Jan 13, 2003 11:52:25 PM
> com.awoma.ts.ui.impl.XHTML11Window load
> FINEST: Parsing of emailpassword.xhtml took 5227 ms
> Jan 13, 2003 11:52:25 PM com.awoma.ts.ui.Store add
> INFO: Window definition emailpassword.xhtml added.
> Jan 13, 2003 11:52:25 PM
> com.awoma.ts.ui.impl.XHTML11Window load
> FINEST: Creating parser took 10 ms
> Jan 13, 2003 11:52:29 PM
> com.awoma.ts.ui.impl.XHTML11Window load
> FINEST: Parsing of emailpassword2.xhtml took 3085 ms
> Jan 13, 2003 11:52:29 PM com.awoma.ts.ui.Store add
> INFO: Window definition emailpassword2.xhtml added.
> Jan 13, 2003 11:52:29 PM
> com.awoma.ts.ui.impl.XHTML11Window load
> FINEST: Creating parser took 0 ms
> Jan 13, 2003 11:52:29 PM
> com.awoma.ts.ui.impl.XHTML11Window load
> FINEST: Parsing of emailpassword3.xhtml took 10 ms
> Jan 13, 2003 11:52:29 PM com.awoma.ts.ui.Store add
> INFO: Window definition emailpassword3.xhtml added.
> Jan 13, 2003 11:52:29 PM
> com.awoma.ts.ui.impl.XHTML11Window load
> FINEST: Creating parser took 0 ms
> Jan 13, 2003 11:52:31 PM
> com.awoma.ts.ui.impl.XHTML11Window load
> FINEST: Parsing of emailpassword4.xhtml took 2774 ms
>
> All files are identical, except #3 where I removed
> all references to the
> external world.
>
> I use Xerces J 2.2.1 (according to build.xml).
>
> Conclusions & questions:
> 1/ Creation of DOMParser() is slow the first time,
> but ridiculous
> afterwards, so there is no need for enhancing that
> much.
> 2/ My parser seems to want to check the validity
> through external
> connection. How can I remove those without modifying
> all my files?
>
> jgp
>
> > -----Original Message-----
> > From: Simon Kitching
> [mailto:simon@(protected)]
> > Sent: Monday, January 13, 2003 23:24
> > To: jgp@(protected)
> > Cc: xerces-j-user@(protected)
> > Subject: Re: Enhancing parsing performance
> >
> > Hi Jean Georges,
> >
> > Firstly, does the document you are parsing contain
> a DTD or schema
> > reference? If it uses http://acme.com/xyz.dtd,
> then much of your parsing
> > time may actually be in retrieval of the remote
> dtd. And if the
> > dtd/schema is large then time will be spent
> processing it. If this is
> > the case, there are optimisations available for
> both these problems.
> >
> > Secondly, you don't say exactly what you are
> timing. Is it the complete
> > application time, or the time taken by the method
> you include below, or
> > just the time for the parse method?
> >
> > Thirdly, you don't mention which version of Xerces
> you are using...
> >
> > Providing information on the above would allow
> people to provide better
> > suggestions for you..
> >
> > I certainly see better performance than you do, so
> there is hope :-)
> >
> > Regards,
> >
> > Simon
> >
> > On Tue, 2003-01-14 at 10:56, Jean Georges PERRIN
> wrote:
> > > Hi,
> > >
> > > Thanks for those who helped me with cloning...
> > >
> > > I am a little surprised with performance. Maybe
> there are some basic
> > things
> > > I am doing wrong.
> > >
> > > I am parsing a 3 Kb XHTML file and it takes me
> about 4s, cloning the
> > tree
> > > takes me roughly a ridiculous amount of time
> (10ms). This on an Athlon
> > XP
> > > 1800+ running XP (sure I could switch to Linux
> but it is not planned for
> > now
> > > :) ).
> > >
> > > My code for parsing:
> > > protected void load () {
> > > DOMParser parser;
> > >
> > > try {
> > > parser = new DOMParser();
> > > }
> > > catch (Exception e) {
> > > log.severe ("Error: Unable to instantiate
> parser");
> > > return;
> > > }
> > >
> > > try {
> > > parser.parse(m_file.toURI().toString());
> > > m_document = parser.getDocument();
> > > }
> > > catch (SAXParseException e) {
> > > // ignore
> > > }
> > > catch (Exception e) {
> > > String msg;
> > > msg = ("Error: Parse error occurred, " +
> e.getMessage());
> > > if (e instanceof SAXException) {
> > > e = ((SAXException)e).getException();
> > > }
> > > msg += '\n' + e.toString();
> > > log.severe (msg);
> > > }
> > > }
> > >
> > > Questions:
> > > 1/ is static'ing my parser will enhance the
> process?
> > > 2/ can I "pre" create some objects I can reuse?
> > > 3/ are there some eventual verification I can
> turn
=== message truncated ===
__________________________________________________
Do you Yahoo!?
Yahoo! Mail Plus - Powerful. Affordable. Sign up now.
http://mailplus.yahoo.com
---------------------------------------------------------------------
To unsubscribe, e-mail: xerces-j-user-unsubscribe@(protected)
For additional commands, e-mail: xerces-j-user-help@(protected)
|
|
