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我有一个长度为2.2亿(固定)的int和float数组。现在,我想要将这些阵列存储/上传到内存和磁盘。目前,我正在使用Java NIO的FileChannel和MappedByteBuffer来解决这个问题。它工作正常,但需要将近5秒钟(挂钟时间)用于将数组存储/上载到内存或从磁盘上传数组。其实,我想要更快一点。任何人都可以帮助我,是否有任何内置的java库/数据库/任何其他方法来更快地上传/存储阵列?我特别关心从磁盘上传到内存。我想让它更快。所以,如果存储时间会增加,我没有问题。提前致谢。Java - 存储和上传数组到/从内存到磁盘
我使用下面给出(如果需要)的代码:
int savenum = 220000000 ;
public void save() {
try {
long l = 0 ;
FileChannel channel = new RandomAccessFile(str1, "rw").getChannel();
MappedByteBuffer mbb = channel.map(FileChannel.MapMode.READ_WRITE, 0, savenum * 8);
mbb.order(ByteOrder.nativeOrder());
for(int i = 0 ; i < savenum ; i++){
l = a[i] ;
mbb.putLong(l);
}
channel.close();
FileChannel channel1 = new RandomAccessFile(str2, "rw").getChannel();
MappedByteBuffer mbb1 = channel1.map(FileChannel.MapMode.READ_WRITE, 0, savenum * 4);
mbb1.order(ByteOrder.nativeOrder());
for(int i = 0 ; i < savenum ; i++){
int ll = b[i] ;
mbb1.putInt(ll);
}
channel1.close();
}
catch (Exception e){
System.out.println("IOException : " + e);
}
}
public void load(){
try{
FileChannel channel2 = new RandomAccessFile(str1, "r").getChannel();
MappedByteBuffer mbb2 = channel2.map(FileChannel.MapMode.READ_ONLY, 0, channel2.size());
mbb2.order(ByteOrder.nativeOrder());
assert mbb2.remaining() == savenum * 8;
for (int i = 0; i < savenum; i++) {
long l = mbb2.getLong();
a[i] = l ;
}
channel2.close();
FileChannel channel3 = new RandomAccessFile(str2, "r").getChannel();
MappedByteBuffer mbb3 = channel3.map(FileChannel.MapMode.READ_ONLY, 0, channel3.size());
mbb3.order(ByteOrder.nativeOrder());
assert mbb3.remaining() == savenum * 4;
for (int i = 0; i < savenum; i++) {
int l1 = mbb3.getInt();
b[i] = l1 ;
}
channel3.close();
}
catch(Exception e){
System.out.println(e) ;
}
}
对于4.4亿件物品,5秒听起来不错。 –
@HunterMcMillen,我想要更快:)。 – Arpssss
文件在磁盘上有多大?我倾向于同意亨特 - 时间对我来说听起来相当不错。显然你可以升级你的电脑(例如用RAID)来提高磁盘性能?不确定SSD有助于写入? – davidfrancis