Re: [lc-devel] Compressed Caching on 2.6

[Nitin G. <nit...@gm...>]

Hi,

>
>> >
>> > About CC, I and Briglia (and...@gm...
>> > <mailto:and...@gm...>) are making some tests with
>> > Rodrigo Castro version (kernel 2.4) for ARM platform. We are studying
>> > a possible port for 2.6 and would like to cooperate with project.
>> >
>>
>> Great!
>>
>> My exams (and other misc things) just ended today...now I can really
>> jump for compressed caching :)
>> Are you doing ccaching for "general" desktop systems or some kind of
>> embedded device?
>
> Some kind of embedded device. :) Actually we tested and did some
> measurements using the Rodrigo's patches for kernel 2.4.18. We tried
> to implement a swap compression on 2.6 kernel, but we stoped when
> recording to disk presented itself as a problem.
>
(I assume you are using flash disks for storage).
So, have you dropped the idea of swap to flash disks? (Compressed) 
Swapping to flash disks have lots of issues as far as I have read about it.

>> Just in case you didn't notice it earlier -- I have made a page
>> linux-mm.org/CompressedCaching giving all the details collected by now
>> for ccaching implementation on 2.6.x kernels (CompressedCaching/Code has
>> the bare bones implementation created by now). Also, this is where I'll
>> keep track of the project.
>
> Yes, we have been visiting your project's site. Will you use just the
> site or we should communicate by this list as well?
>
The site is just to keep design details updated. We can always 
communicate through this list (and #linux-mm-cc).
>>
>> I intend to now focus on ccaching w.r.t OLPC systems. Thus, I'll now
>> work on handling anon pages first instead of page cache pages.
>>
>> The biggest thing is compression storage structure -- heart of all this
>> work. I've actually received 0 feedback on this by now. Since that
>> involves my semi-random guess work too, it really needs your help :)
>> All other work revolves around this thing. In particular please see
>> 'Problems' listed at end of that page.
>
> Ok. We intend help you and the others to design this crucial part.
Thanks!
> How about that chunks approach? We thought you already decided to use it.
Yes, I've decided to use this chunk approach as described on 
CompressedCaching page. But, still if you can give your feedback, we can 
always improve it.
>>
>> PS: I've 0 idea of ARM systems!
>
> Don't worry about this. The kernel core is similar. Of course we've
> other issues to care about, but the design of ccaching can be used on
> both systems.
>

Best Regards,
Nitin Gupta