[Boost-users] iostream large file - performance

From: Aljaz (aljaz.fajmut_at_[hidden])
Date: 2007-03-08 07:31:00

Hello..

I've been testing fstream libary to read a huge text file (45 megabytes), 
which has around 2 million lines..

When I do (using fstream):

Code:
int line = 0;
string str;
ifstream is("file.txt");
while (!is.eof()) {
        getline(is, str);
        line++;
}It takes about 9 seconds to read the whole file..

If I open file it with any 'good' text editor (editplus, notepad++ for 
instance) it takes a few seconds to read/load the whole file..

So I'm wondering.. What am I doing wrong?
What should I do to achieve that speed - better preformance?
Can boost::iostream do any better?

Another thing:
I tried writing data to deque (deque.pushback(str)) and was shocked on what 
happened.. It took ages to process the file, cpu constant at 99% so I closed 
the program after around 3 minutes..

Whats the 'proper' way to read files to memory? How do text editors do this? 
They load the same file in 4 seconds!
I need a fastest way to read about 10 000 lines from text file at once..

Any help highly appreciated!
Best regards
A