Re: [RFC 1/2] deactive invalidated pages

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Tue, Nov 23, 2010 at 2:01 PM, Andrew Morton
<akpm@xxxxxxxxxxxxxxxxxxxx> wrote:
> On Tue, 23 Nov 2010 13:52:05 +0900 Minchan Kim <minchan.kim@xxxxxxxxx> wrote:
>
>> >> +/*
>> >> + * Function used to forecefully demote a page to the head of the inactive
>> >> + * list.
>> >> + */
>> >
>> > This comment is wrong? __The page gets moved to the _tail_ of the
>> > inactive list?
>>
>> No. I add it in _head_ of the inactive list intentionally.
>> Why I don't add it to _tail_ is that I don't want to be aggressive.
>> The page might be real working set. So I want to give a chance to
>> activate it again.
>
> Well..  why?  The user just tried to toss the page away altogether.  If
> the kernel wasn't able to do that immediately, the best it can do is to
> toss the page away asap?
>
>> If it's not working set, it can be reclaimed easily and it can prevent
>> active page demotion since inactive list size would be big enough for
>> not calling shrink_active_list.
>
> What is "working set"?  Mapped and unmapped pagecache, or are you
> referring solely to mapped pagecache?

I mean it's mapped by other processes.

>
> If it's mapped pagecache then the user was being a bit silly (or didn't
> know that some other process had mapped the file).  In which case we
> need to decide what to do - leave the page alone, deactivate it, or
> half-deactivate it as this patch does.


What I want is the half-deactivate.

Okay. We will use the result of invalidate_inode_page.
If fail happens by page_mapped, we can do half-deactivate.
But if fail happens by dirty(ex, writeback), we can add it to tail.
Does it make sense?



-- 
Kind regards,
Minchan Kim

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxxx  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/
Don't email: <a href


[Index of Archives]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [IETF Annouce]     [Bugtraq]     [Linux]     [Linux OMAP]     [Linux MIPS]     [ECOS]     [Asterisk Internet PBX]     [Linux API]