Re: posix_fadvise

[Jamie Lokier]

Ulrich Drepper wrote:
> > What does POSIX_FADV_DONTNEED mean?  MADV_DONTNEED has at least three
> > incompatible meanings between different unix systems...
> 
> Their definition is:
> 
>   Specifies that the applicatione xpects that it will not access the
>   specified data in the near future.

Ok.  You should be aware that the present Linux implementation of
MADV_DONTNEED is "nukes dirty data".  Do you have a POSIX standard that
says POSIX MADV_DONTNEED should be similar to POSIX_FADV_DONTNEED?

There was some discussion on linux-mm about renaming this behaviour to
MADV_WONTNEED or MADV_DISCARD to avoid ambiguity.  Some other OSes
implement MADV_DONTNEED by discarding data, but there are at least two
other semantics around including one like POSIX_FADV_DONTNEED.

enjoy,
-- Jamie