[Devel] Re: [PATCH 8/8] Per-container pages reclamation

[Pavel Emelianov]

Balbir Singh wrote:
> Pavel Emelianov wrote:
>> Balbir Singh wrote:
>>> Pavel Emelianov wrote:
>>>> Implement try_to_free_pages_in_container() to free the
>>>> pages in container that has run out of memory.
>>>>
>>>> The scan_control->isolate_pages() function isolates the
>>>> container pages only.
>>>>
>>> Pavel,
>>>
>>> I've just started playing around with these patches, I preferred
>>> the approach of v1. Please see below
>>>
>>>> +static unsigned long isolate_container_pages(unsigned long nr_to_scan,
>>>> +        struct list_head *src, struct list_head *dst,
>>>> +        unsigned long *scanned, struct zone *zone)
>>>> +{
>>>> +    unsigned long nr_taken = 0;
>>>> +    struct page *page;
>>>> +    struct page_container *pc;
>>>> +    unsigned long scan;
>>>> +    LIST_HEAD(pc_list);
>>>> +
>>>> +    for (scan = 0; scan < nr_to_scan && !list_empty(src); scan++) {
>>>> +        pc = list_entry(src->prev, struct page_container, list);
>>>> +        page = pc->page;
>>>> +        if (page_zone(page) != zone)
>>>> +            continue;
>>> shrink_zone() will walk all pages looking for pages belonging to this
>>
>> No. shrink_zone() will walk container pages looking for pages in the
>> desired zone.
>> Scann through the full zone is done on global memory shortage.
>>
> 
> Yes, I see that now. But for each zone in the system, we walk through the
> containers list - right?

Right.

> I have some more fixes, improvements that I want to send across.
> I'll start sending them out to you as I test and verify them.

That's great! :) Thanks for participation.

> 
>>> container and this slows down the reclaim quite a bit. Although we've
>>> reused code, we've ended up walking the entire list of the zone to
>>> find pages belonging to a particular container, this was the same
>>> problem I had with my RSS controller patches.
>>>
>>>> +
>>>> +        list_move(&pc->list, &pc_list);
>>>> +
>>>
>>
> 
>