Re: [TESTCASE] Clean pages clogging the VM

Wu Fengguang
2010-08-19T21:09:29Z

On Thu, Aug 19, 2010 at 07:51:06PM +0800, Johannes Weiner wrote:
> I am currently trying to get rid of all the congestion_wait() in the VM.
> They are used for different purposes, so they need different replacement
> mechanisms.
>
> I saw Shaohua's patch to make congestion_wait() cleverer. But I really
> think that congestion is not a good predicate in the first place. Why
> would the VM care about IO _congestion_? It needs a bunch of pages to
> complete IO, whether the writing device is congested is not really
> useful information at this point, I think.

I have the same feeling that the congestion_wait() calls are not
pertinent ones. I'm glad to see people working on that exploring
all possible replacement schemes.

Thanks,
Fengguang