What Is /proc/kcore?
None of the files in /proc are really there--they're all, "pretend,"
files made up by the kernel, to give you information about the system
and don't take up any hard disk space.
/proc/kcore is like an "alias" for the memory in your computer. Its
size is the same as the amount of RAM you have, and if you read it as
a file, the kernel does memory reads.
如下截图可以看到，这个文件标注的大小已经达到128T了，
而描述中说此文件是内存的别名，我内存16G，不是128T
