[PDFBOX-5286] Runtime degredation in RC1 and alpha2

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 3.0.0 PDFBox
• Fix Version/s: 3.0.0 PDFBox
• Component/s: Parsing
• Assignee: Andreas Lehmkühler
• Reporter: Maruan Sahyoun
• Created: 03/Oct/21 10:22
• Updated: 18/Aug/23 05:46
• Resolved: 12/Mar/22 10:41

Description

working/reviewing PDFBOX-5068 and PDFBOX-5263 I've experiencing runtime issues for both 3.0.0-RC1 and 3.0.0-alpha2 when loading and saving a large PDF

https://crossasia-books.ub.uni-heidelberg.de/xasia/reader/download/506/506-42-86246-2-10-20190822.pdf

version	runtime in millis
2.0.24	2076
3.0.0-RC1	219472
3.0.0-alpha2	282284

Basic test:

long start = System.currentTimeMillis();
PDDocument pdf = Loader.loadPDF(new File("506-42-86246-2-10-20190822.pdf"));
pdf.save(new NullOutputStream());
pdf.close();        
long end = System.currentTimeMillis();      
System.out.println("Elapsed Time in milliseconds: "+ (end-start));     

with NullOuputStream

package org.apache.pdfbox;

import java.io.IOException;
import java.io.OutputStream;

public class NullOutputStream extends OutputStream {

    @Override
    public void write(byte[] b) throws IOException {
        // don't write anything
    }

    @Override
    public void write(byte[] b, int off, int len) throws IOException {
        // don't write anything
    }

    @Override
    public void write(int b) throws IOException {
        // don't write anything
    }
}

I've also running tests using JMH - they support these numbers. The difference in numbers for RC1/alpha2 are within a regular variation.