java – 为什么我的流复制过程的性能稳定下降
作者:互联网
在复制大文件期间,此代码的工作速度越来越慢.难道我做错了什么?
InputStream ms2 = new BufferedInputStream(new FileInputStream("/home/fedd/Videos/homevid.mp4"));
OutputStream fos2 = new BufferedOutputStream(new FileOutputStream("testfile2.mp4", true));
try {
int byt;
int i = 0;
long time = System.currentTimeMillis();
while ((byt = ms2.read()) != -1) {
fos2.write(byt);
i++;
if (i > 100000) {
i = 0;
long took = System.currentTimeMillis() - time;
System.out.println("100000 bytes took " + took + " milliseconds which means " + (100000000 / took) + " bytes per second");
}
}
fos2.close();
ms2.close();
} catch (Exception e) {
throw new RuntimeException(e);
}
我的Java是:
openjdk 10.0.2 2018-07-17 OpenJDK Runtime Environment (build
10.0.2+13-Ubuntu-1ubuntu0.18.04.4)OpenJDK 64-Bit Server VM (build 10.0.2+13-Ubuntu-1ubuntu0.18.04.4,
mixed mode)
解决方法:
每次比较后,您需要重置基准’时间’.试试这个:
if (i > 100000) {
i = 0;
long took = System.currentTimeMillis() - time;
time = System.currentTimeMillis();
System.out.println("100000 bytes took " + took + " milliseconds which means " + (100000000 / took) + " bytes per second");
}
标签:java,java-io 来源: https://codeday.me/bug/20190716/1473773.html