Propose to Use madvise API on Runtime Loader

[lin zuojian]

On Fri, May 23, 2014 at 01:26:35AM -0400, Rich Felker wrote:
> They are the same physical pages, so I don't see how you can drop one
> without dropping the other.
> 
    When the virtual memory area specified is huge, hopefully there are
    many pmd pages will get dropped. Even some of the pud will get
    dropped.
> RSS is not "accountable memory". It's largely meaningless, because it
> includes memory that can be dropped at any time (without a need to
> save it to swap). Defining a process's memory usage in a meaningful
> way is difficult, but dirty pages, commit charge, and total RW mapping
> sizes are more likely to be useful metrics than RSS is.
    But it's one the most important element that OOM killer considers.
--
Lin Zuojian