# Re: \[PATCH v10 1/7\] mm: support madvise(MADV\_FREE)

- From: Zhang Yanfei \<hidden\>
- Date: 2014-07-08 03:54:57 
- List: linux-api
- Page: https://ratatoskr.run/linux-api/2014/07/4289163
- Thread: https://ratatoskr.run/linux-mm/2014/07/4288002/t.md

```text
Hi Minchan,

On 07/07/2014 08:53 AM, Minchan Kim wrote:
> Linux doesn't have an ability to free pages lazy while other OS
> already have been supported that named by madvise(MADV_FREE).
> 
> The gain is clear that kernel can discard freed pages rather than
> swapping out or OOM if memory pressure happens.
> 
> Without memory pressure, freed pages would be reused by userspace
> without another additional overhead(ex, page fault + allocation
> + zeroing).
> 
> How to work is following as.
> 
> When madvise syscall is called, VM clears dirty bit of ptes of
> the range. 

This should be updated because the implementation has been changed.
It also remove the page from the swapcache if it is.

Thank you for your effort!

-- 
Thanks.
Zhang Yanfei
```