Re: reading a large text file that is part of a very tight loop
"thebad1" <thomas.hodder@gmail.com> wrote in news:1168251545.671290.310410@
51g2000cwl.googlegroups.com:
OK, while this isn;t the exact code, its the relevant section....
static final int numRatings = 100456599;
static final int epoch = 100000;
FileChannel fc = new FileInputStream (filepath).getChannel();
MappedByteBuffer mappedBuff = fc.map(FileChannel.MapMode.READ_ONLY, 0,
fc.size());
for (int epoch = 0; epoch < numEpochs; epoch++) {
mappedBuff.rewind();
for (int k = 0; k < numRatings; k++) {
cUser = mappedBuff.getInt();
cMovie = (int)mappedBuff.getShort();
cRating = (int)mappedBuff.get();
//doStuff;
}
}
Quite different from what was originally posted! Perhaps you have been
experimenting and learning along the way.
At this point I will shut up on this topic, as I have no experience with
FileChannel and MappedByteBuffer.
Anyone with experience have suggestions for speeding this up?
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