[linux-mm-cc] Re: [lc-devel] Chunk list issues

[Nitin Gupta]

Hi Anderson,

Anderson Briglia wrote:
> Hi Gupta and others,
> 
> I have a doubt related to chunk operations:
> 
> - I guess you will use the virtual swap as the compressed cache for
> anon pages, right? If yes, how will you swapin/swapout chunks? If a
> single chunk points to a portion of a physical page, and the
> swapin/swapout operations handle entire pages of data.

Yes, vswap is for anon pages. I think you are mistaken somewhere...I'm not using 
bio structs or anything to swapin/out pages from vswap.
So, for swap out: Get enough free chunks from free list and store compressed 
page in them.
And, for swap in: chunk_head->chunk_list gives to first chunk and chunks are 
linked. So, you can get data from all these chunks, (maybe) collect them in a 
page, decompress it and return to caller.

I have started implementation for this compression structure and post when its 
ready. This should also reveal possible problems which I don't see now.

Cheers,
Nitin


> 
> On 6/27/06, Nitin Gupta <nitingupta.mail at gmail.com> wrote:
>> Hi Mauricio,
>>
>> I am currently implementing compression structure in compress-test module (see
>> CompressedCaching/Code). This can then be transfered to ccache git tree.
>>
>> Also, I've made some changes to chunk_head and chunk structs which further
>> compact them by few bytes. I will update Wiki page soon.
>>
>> I think your code will be useful too. Thanks.
>>
>> Cheers,
>> Nitin Gupta
>>
>>
>> Mauricio Lin wrote:
>>> In order to make the development of chunk list operations easier to
>>> debug, I have created a module that helps gradually to put more chunk
>>> list operation an test it.
>>>
...