Overview

'bigdoc' allows you to handle gigabyte order files easily with high performance. You can search bytes or words / read data/text from huge files.

It is licensed under MIT license.

Quick start

Search sequence of bytes from a big file quickly.

Search mega-bytes,giga-bytes order file.

package org.example;

import java.io.File;
import java.util.List;

import org.riversun.bigdoc.bin.BigFileSearcher;

public class Example {

	public static void main(String[] args) throws Exception {

		byte[] searchBytes = "hello world.".getBytes("UTF-8");

		File file = new File("/var/tmp/yourBigfile.bin");

		BigFileSearcher searcher = new BigFileSearcher();

		List<Long> findList = searcher.searchBigFile(file, searchBytes);

		System.out.println("positions = " + findList);
	}
}

Example code for canceling a search in progress

When used asynchronously, #cancel can be used to stop the process in the middle of a search.

package org.riversun.bigdoc.bin;

import java.io.File;
import java.io.UnsupportedEncodingException;
import java.util.List;

import org.riversun.bigdoc.bin.BigFileSearcher.OnRealtimeResultListener;

public class Example {

  public static void main(String[] args) throws UnsupportedEncodingException, InterruptedException {
    byte[] searchBytes = "sometext".getBytes("UTF-8");
    
    File file = new File("path/to/file");

    final BigFileSearcher searcher = new BigFileSearcher();

    searcher.setUseOptimization(true);
    searcher.setSubBufferSize(256);
    searcher.setSubThreadSize(Runtime.getRuntime().availableProcessors());

    final SearchCondition sc = new SearchCondition();
    
    sc.srcFile = file;
    sc.startPosition = 0;
    sc.searchBytes = searchBytes;

    sc.onRealtimeResultListener = new OnRealtimeResultListener() {

      @Override
      public void onRealtimeResultListener(float progress, List<Long> pointerList) {
        System.out.println("progress:" + progress + " pointerList:" + pointerList);
      }
    };

    final Thread th = new Thread(new Runnable() {

      @Override
      public void run() {
        List<Long> searchBigFileRealtime = searcher.searchBigFile(sc);
      }
    });

    th.start();

    Thread.sleep(1500);

    searcher.cancel();

    th.join();

  }
}

Performance Test

Search sequence of bytes from big file

Environment

Tested on AWS t2.*

Results

CPU Instance	EC2 t2.2xlarge vCPU x 8,32GiB	EC2 t2.xlarge vCPU x 4,16GiB	EC2 t2.large vCPU x 2,8GiB	EC2 t2.medium vCPU x 2,4GiB
File Size	Time(sec)	Time(sec)	Time(sec)	Time(sec)
10MB	0.5s	0.6s	0.8s	0.8s
50MB	2.8s	5.9s	13.4s	12.8s
100MB	5.4s	10.7s	25.9s	25.1s
250MB	15.7s	32.6s	77.1s	74.8s
1GB	55.9s	120.5s	286.1s	-
5GB	259.6s	566.1s	-	-
10GB	507.0s	1081.7s	-	-

Please Note

• Processing speed depends on the number of CPU Cores(included hyper threading) not memory capacity.
• The result is different depending on the environment of the Java ,Java version and compiler or runtime optimization.

Architecture and Tuning

You can tune the performance using the following methods. It can be adjusted according to the number of CPU cores and memory capacity.

• BigFileSearcher#setBlockSize
• BigFileSearcher#setMaxNumOfThreads
• BigFileSearcher#setBufferSizePerWorker
• BigFileSearcher#setBufferSize
• BigFileSearcher#setSubThreadSize

BigFileSearcher can search for sequence of bytes by dividing a big file into multiple blocks. Use multiple workers to search for multiple blocks concurrently. One worker thread sequentially searches for one block. The number of workers is specified by #setMaxNumOfThreads. Within a single worker thread, it reads and searches into the memory by the capacity specified by #setBufferSize. A small area - used to compare sequence of bytes when searching - is called a window, and the size of that window is specified by #setSubBufferSize. Multiple windows can be operated concurrently, and the number of conccurent operations in a worker is specified by #setSubThreadSize.

More Details

See javadoc as follows.

https://riversun.github.io/javadoc/bigdoc/

Downloads

maven

• You can add dependencies to maven pom.xml file.

<dependency>
    <groupId>org.riversun</groupId>
    <artifactId>bigdoc</artifactId>
    <version>0.4.0</version>
</dependency>