On Thu, Jan 14, 2010 at 09:31:03AM +0900, KOSAKI Motohiro wrote:

quoted

quoted

If application does mlockall(MCL_FUTURE) it is no longer possible to mmap
file bigger than main memory or allocate big area of anonymous memory
in a thread safe manner. Sometimes it is desirable to lock everything
related to program execution into memory, but still be able to mmap
big file or allocate huge amount of memory and allow OS to swap them on
demand. MAP_UNLOCKED allows to do that.
 
Signed-off-by: Gleb Natapov <redacted>
---

I get reports that people find this useful, so resending.

This description is still wrong. It doesn't describe why this patch is useful.

I think the text above describes the feature it adds and its use
case quite well. Can you elaborate what is missing in your opinion,
or suggest alternative text please?

My point is, introducing mmap new flags need strong and clearly use-case.
All patch should have good benefit/cost balance. the code can describe the cost,
but the benefit can be only explained by the patch description.

I don't think this poor description explained bit benefit rather than cost.
you should explain why this patch is useful and not just pretty toy.