Re: [RFC] mm: remove swapcache page early

Simon Jeons
2013-04-08T01:51:43Z

On 04/08/2013 09:48 AM, Minchan Kim wrote:
> Hello Simon,
>
> On Sun, Apr 07, 2013 at 03:26:12PM +0800, Simon Jeons wrote:
>> Ping Minchan.
>> On 04/02/2013 09:40 PM, Simon Jeons wrote:
>>> Hi Hugh,
>>> On 03/28/2013 05:41 AM, Hugh Dickins wrote:
>>>> On Wed, 27 Mar 2013, Minchan Kim wrote:
>>>>
>>>>> Swap subsystem does lazy swap slot free with expecting the page
>>>>> would be swapped out again so we can't avoid unnecessary write.
>>>> so we can avoid unnecessary write.
>>> If page can be swap out again, which codes can avoid unnecessary
>>> write? Could you point out to me? Thanks in advance. ;-)
> Look at shrink_page_list.
>
> 1) PageAnon(page) && !PageSwapCache()
> 2) add_to_swap's SetPageDirty
> 3) __remove_mapping
>
> P.S)
> It seems you are misunderstanding. Here isn't proper place to ask a
> question for your understanding the code. As I know, there are some
> project(ex, kernelnewbies) and books for study and sharing the
> knowledge linux kernel.
>
> I recommend Mel's "Understand the Linux Virtual Memory Manager".
> It's rather outdated but will be very helpful to understand VM of
> linux kernel. You can get it freely but I hope you pay for.
> So if author become a billionaire by selecting best book in Amazon,
> he might print out second edition which covers all of new VM features
> and may solve all of you curiosity.
>
> It would be a another method to contribute open source project. :)
>
> I believe you talented developers can catch it up with reading the
> code enoughly and find more bonus knowledge. I think it's why our senior
> developers yell out RTFM and I follow them.

What's the meaning of RTFM?

>
> Cheers!
>
>