Re: [PATCH] mm, swap: Make VMA based swap readahead configurable

From: Huang\, Ying
Date: Tue Sep 26 2017 - 21:38:22 EST


Michal Hocko <mhocko@xxxxxxxxxx> writes:

> On Thu 21-09-17 09:33:10, Huang, Ying wrote:
>> From: Huang Ying <ying.huang@xxxxxxxxx>
>>
>> This patch adds a new Kconfig option VMA_SWAP_READAHEAD and wraps VMA
>> based swap readahead code inside #ifdef CONFIG_VMA_SWAP_READAHEAD/#endif.
>> This is more friendly for tiny kernels.
>
> How (much)?

OK. I will measure it.

>> And as pointed to by Minchan
>> Kim, give people who want to disable the swap readahead an opportunity
>> to notice the changes to the swap readahead algorithm and the
>> corresponding knobs.
>
> Why would anyone want that?
>
> Please note that adding new config options make the already complicated
> config space even more problematic so there should be a good reason to
> add one. Please make sure your justification is clear on why this is
> worth the future maintenance and configurability burden.

Hi, Minchan,

Could you give more information on this?

Best Regards,
Huang, Ying