Re: Problem in Page Cache Replacement

Metin Döşlü
2012-11-24T15:06:32Z

On Thu, Nov 22, 2012 at 5:41 PM, Fengguang Wu <fengguang.wu@intel.com> wrote:
> On Wed, Nov 21, 2012 at 12:07:22PM +0200, Metin Döşlü wrote:
>> On Wed, Nov 21, 2012 at 12:00 PM, Jaegeuk Hanse <jaegeuk.hanse@gmail.com> wrote:
>> >
>> > On 11/21/2012 05:58 PM, metin d wrote:
>> >
>> > Hi Fengguang,
>> >
>> > I run tests and attached the results. The line below I guess shows the data-1 page caches.
>> >
>> > 0x000000080000006c 6584051 25718 __RU_lA___________________P________ referenced,uptodate,lru,active,private
>> >
>> >
>> > I thinks this is just one state of page cache pages.
>>
>> But why these page caches are in this state as opposed to other page
>> caches. From the results I conclude that:
>>
>> data-1 pages are in state : referenced,uptodate,lru,active,private
>
> I wonder if it's this code that stops data-1 pages from being
> reclaimed:
>
> shrink_page_list():
>
> if (page_has_private(page)) {
> if (!try_to_release_page(page, sc->gfp_mask))
> goto activate_locked;
>
> What's the filesystem used?

It was ext3.

>> data-2 pages are in state : referenced,uptodate,lru,mappedtodisk
>
> Thanks,
> Fengguang

--
Metin Döşlü