在 Java 和 .Net 中从 DVD 读取速度非常慢

发布于 2024-08-04 16:09:57 字数 545 浏览 2 评论 0原文

我注意到在两个生成文件哈希的应用程序（一个用 Java 编写，另一个用 C# 编写）中，从 DVD 读取时的性能非常糟糕。我使用的是Windows XP SP3。我从噪音中注意到，驱动器在读取一堆块后不断旋转，导致读取之间有几秒钟的暂停。

奇怪的是，当我使用资源管理器将文件复制到硬盘驱动器或使用 md5sum（用 C 编写的实用程序）时，不会发生这种情况。还。当使用相同硬件在 Linux 中运行时，Java 应用程序运行良好。

private static final byte[] m_buf = new byte[1048576*3];
...
//Using a BufferedInputStream makes no difference
InputStream in = new FileInputStream(file);
while((last_read = in.read(m_buf)) != -1){
    update_hash(m_buf, 0, last_read);           
}
in.close();

有什么提示吗？

谢谢。

原文

I noticed in two applications to generate hashes of files, one written in Java and the other in C#, that the performance is horrible when reading from a DVD. I'm using Windows XP SP3. I noticed from the noise, that the drive keeps spinning down after reading a bunch of blocks, causing pauses of a couple of seconds between reads.

The strange thing, is that this doesn't happen when I use explorer to copy the files to my hard drive or when using md5sum (a utility written in C). Also. When running in Linux using the same hardware, the Java application works fine.

private static final byte[] m_buf = new byte[1048576*3];
...
//Using a BufferedInputStream makes no difference
InputStream in = new FileInputStream(file);
while((last_read = in.read(m_buf)) != -1){
    update_hash(m_buf, 0, last_read);           
}
in.close();

Any hints?

Thanks.

分享到QQ

分享到微博