※ 引述《ydaniel00 (Daniel)》之铭言：
: Loading the covtype file takes anywhere from 5 to 10 minutes
: on a P4 2.8G depending on CPU usage. However, the fact that
: covtype matrix needs 1 GB of RAM may be a potential
: problem.
I recommend using gc() function before and after file loading to
release some system memory from R.
For covtype matrix, we have 55*581012 entries. Assume each
entries takes 8 bytes (type=double), overall memory = 255645280 bytes
= 243.8 Mb. With original loaded file size 86Mb, at least 330 Mb is
necessary.
In my experience, it's usually more, but about 400Mb is the upper
bound for most evaluation times (Sometimes R may wierdly rush to 600Mb, but
not often, don't know why, it should take time to understand its
underlying.)
I'm interesting about whether someone uses machine with less than
500 Mb(or even 256) mem for this job running, maybe the Hard Disk
will dancing around all the time.