Re: [-mm] Make the memory controller more desktop responsive

[Balbir Singh <balbir@linux.vnet.ibm.com>]

KAMEZAWA Hiroyuki wrote:
> On Thu, 03 Apr 2008 15:02:53 +0530
> Balbir Singh <balbir@linux.vnet.ibm.com> wrote:
>> This patch makes the memory controller more responsive on my desktop.
>>
>> Here is what the patch does
>>
>> 1. Reduces the number of retries to 2. We had 5 earlier, since we
>>    were controlling swap cache as well. We pushed data from mappings
>>    to swap cache and we needed additional passes to clear out the cache.
> 
> Hmm, what this change improves ?
> I don't want to see OOM.
> 

I had set it to 5 earlier, since the swap cache came back to our memory
controller, where it was accounted. I have not seen OOM with it on my desktop,
but at some point if the memory required is so much that we cannot fulfill it,
we do OOM. I have not seen any OOM so far with these changes.

>> 2. It sets all cached pages as inactive. We were by default marking
>>    all pages as active, thus forcing us to go through two passes for
>>    reclaiming pages
> Agreed.
> 
>> 3. Removes congestion_wait(), since we already have that logic in
>>    do_try_to_free_pages()
>>
> Agreed.


-- 
	Warm Regards,
	Balbir Singh
	Linux Technology Center
	IBM, ISTL