BufferedOutputStream与NIO写文件对比

数据内容（一行）如下所示

{"MAF":3.86,
"BASE_STATION":"1823,4207,460,0,37;18431,4207,460,0,25;1822,4207,460,0,25;",
"PID_010B":"",
"FUEL":10.49,
"REMARK":31922,
"MILAGE":18.94,
"PID_010C":"",
"PID_010F":"",
"RECEIVED_TIME":"2013-12-04 14:41:59",
"GATHERTIME":"2013-12-04 14:41:49",
"BABV":10.59,
"ACCSTATUS":"0",
"OBD_SPEED":145,
"G_FORCE":-0.49}

第一次：（磁盘非常卡）

名称	文件数	数据条数	单条数据大小	线程数	耗时(s)	备注
BufferedOutputStream	100	7200	约310字节	200	611.557	XP系统，4G内存，4核CPU、apache commons-io组件
FileChannel	100	7200	约310字节	200	637.867	XP系统，4G内存，4核CPU

第二次：（CPU 100%）

名称	文件数	数据条数	单条数据大小	线程数	耗时(s)	备注
BufferedOutputStream	10000	7200	约310字节	200	1963.642	linux系统，2G内存，4核CPU
FileChannel	10000	7200	约310字节	200	1953.116	linux系统，2G内存，4核CPU

代码：

package com.sides.file;

import java.io.File;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;

/****************************************************************************
 * com.sides.file WriteFile.java Created on 2013-12-3
 * @Author: linfenliang
 * @Description:
 * @Version: 1.0
 ***************************************************************************/
public class WriteFile {
	/**
	 * @param args
	 * void
	 * @date 2013-12-3
	 * @version V1.0.0
	 * @author linfenliang
	 * @throws ExecutionException 
	 * @throws InterruptedException 
	 */
	public static void main(String[] args) throws InterruptedException, ExecutionException {
		ExecutorService service = Executors.newFixedThreadPool(200);
		long t0 = System.nanoTime();
		Future<Boolean> future = null;
		for(int i=0;i<10000;i++){
			WriterThread task = new WriterThread(DataFactory.dataList, String.format("/var/lib/log/nio/OBD_DATA%s.dat", i),true);
			future = service.submit(task);
		}
		boolean b = future.get();
		long t1 = System.nanoTime();
		System.out.println(b+",time cost ms:"+(t1-t0)/1000000);

		System.out.println("NIO is OK, ready to BufferedOutputStream write");
		Thread.sleep(5*1000);
		
		long t2 = System.nanoTime();
		Future<Boolean> future2 = null;
		for(int i=0;i<10000;i++){
			WriterThread task = new WriterThread(DataFactory.dataList, String.format("/var/lib/log/buffer/OBD_DATA%s.dat",i),false);
			future2 = service.submit(task);
		}
		boolean isOk = future2.get();
		long t3 = System.nanoTime();
		System.out.println(isOk+",time cost ms:"+(t3-t2)/1000000);
		
		
		System.out.println("BufferedOutputStream is OK, ready to  exit");
		Thread.sleep(5*1000);
		
		System.exit(0);
		
		
		
		
//		deleteFolder("/var/lib/log");
	}

	static void deleteFolder(String path) {
		File f = new File(path);
		if (f.isDirectory()) {
			File[] files = f.listFiles();
			for (File file : files) {
				if (!file.isDirectory()) {
					file.deleteOnExit();
				} else {
					deleteFolder(file.getAbsolutePath());
					boolean b = file.delete();
					System.out.println(b+"--"+file.getAbsolutePath());
				}
			}
		}
}
}

package com.sides.file;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.concurrent.Callable;

import net.sf.json.JSONArray;
import net.sf.json.JSONObject;

import org.apache.commons.io.FileUtils;
import org.apache.commons.io.IOUtils;
import org.apache.log4j.Logger;

/****************************************************************************
 * com.sides.file WriterThread.java Created on 2013-12-3
 * 
 * @Author: linfenliang
 * @Description:
 * @Version: 1.0
 ***************************************************************************/
public class WriterThread implements Callable<Boolean> {
	private static final Logger logger = Logger.getLogger(WriterThread.class);
	private List<Map<String,Object>> dataList;
	private String filePath;
	private boolean nioWrite;
	public WriterThread(List<Map<String,Object>> dataList,String filePath,boolean isNio){
		this.dataList = dataList;
		this.filePath = filePath;
		this.nioWrite = isNio;
	}
	@Override
	public Boolean call() throws Exception {
		try {
			File folder = new File(this.filePath).getParentFile();
			if(!folder.exists()){
				folder.mkdir();
			}
			JSONArray dataArr = JSONArray.fromObject(dataList,DataFactory.jsonConfig);
			for(int i=0;i<720;i++){
				if(nioWrite){
					nioWriteFile(filePath, dataArr);
				}else{
					commonIoWriteFile(filePath, dataArr);
				}
			}
		} catch (Exception e) {
			System.err.println(String.format("data list write error,source data is :%s, filePath is :%s, error message is:%s", dataList,filePath,e));
			return false;
		}
		System.out.println(this.filePath + "finished");
		return true;
	}
	static final void commonIoWriteFile(final String fileName, final Collection data) throws IOException{
		FileUtils.writeLines(new File(fileName), "UTF-8", data, IOUtils.LINE_SEPARATOR_UNIX, true);
	}
	static final void nioWriteFile(final String fileName, final JSONArray arr) throws IOException{
		FileOutputStream fops = new FileOutputStream(fileName,true);
		FileChannel writeChannel = fops.getChannel();
		JSONObject obj = null;
		Iterator<JSONObject> iter = arr.iterator();
		while(iter.hasNext()){
			obj = iter.next();
			writeChannel.write(ByteBuffer.wrap(obj.toString().concat(IOUtils.LINE_SEPARATOR_UNIX).getBytes()));
		}
		writeChannel.close();
		fops.close();
	}
}

测试结果令我很失望，本来打算做原始数据存储的，结果写文件太耗费性能了，无法接受，值得一提的是NIO写大文件

速度还是蛮快的。

下一步打算数据直接存储到内存中，待测试。