Performance issues with XMLTextReader

[Frank Schumacher]

Hi there,

I need to parse a lot of html-files from wikipedia, and I need to do it
as fast as possible. So I started a little testing with XMLTextReader,
but the results I get confuse me. It seems that the Reader ALWAYS needs
about 1 second for the first textReader.Read()

Here's my testcode:

XmlTextReader _myReader = new XmlTextReader(textBox1.Text);
DateTime _firstRead = DateTime.MinValue;

DateTime _start = DateTime.Now;
_myReader.Read();
_firstRead = DateTime.Now;

while (_myReader.Read())
{
}

MessageBox.Show("FirstRead: " + Convert.ToString(_firstRead - _start) +
". Overall: " + Convert.ToString(DateTime.Now - _start));

And here are the results for a 134kb file:
FirstRead: 0.9218750. Overall: 0.9375

I get a similar result for a 15kb file. (And btw. the same result when
using DOM)

Any ideas why it takes so long for the first read and what to do about it?

I have downloaded the whole wikipedia and extract it to the filesystem.
Is that the reason?

Ciao,
Frank

[John Saunders]

"Frank Schumacher" <f_********@informatik.uni-leipzig.dewrote in message
news:uo**************@TK2MSFTNGP02.phx.gbl...

Hi there,

I need to parse a lot of html-files from wikipedia, and I need to do it as
fast as possible. So I started a little testing with XMLTextReader, but
the results I get confuse me. It seems that the Reader ALWAYS needs about
1 second for the first textReader.Read()

Here's my testcode:

XmlTextReader _myReader = new XmlTextReader(textBox1.Text);
DateTime _firstRead = DateTime.MinValue;

DateTime _start = DateTime.Now;
_myReader.Read();
_firstRead = DateTime.Now;

while (_myReader.Read())
{
}

MessageBox.Show("FirstRead: " + Convert.ToString(_firstRead - _start) + ".
Overall: " + Convert.ToString(DateTime.Now - _start));

And here are the results for a 134kb file:
FirstRead: 0.9218750. Overall: 0.9375

I get a similar result for a 15kb file. (And btw. the same result when
using DOM)

Any ideas why it takes so long for the first read and what to do about it?

I have downloaded the whole wikipedia and extract it to the filesystem. Is
that the reason?

Which version of .NET are you running?

John

[Frank Schumacher]

Hi John,

Which version of .NET are you running?

I'm working with Visual Studi 2005, so it is .NET 2.0, I guess.

Ciao,
Frank